GOVERNMENT OF INDIA MINISTRY OF RAILWAYS ......Medha MEI633 EI System is an indigenously developed Electronic Interlocking system and has been installed on a number of stations of

GOVERNMENT OF INDIA

MINISTRY OF RAILWAYS

Maintenance Handbook on

MEDHA MEI633

Electronic Interlocking System

End Users: Signal Maintenance Personnel of Indian Railways

CAMTECH/S/PROJ/2020-21/SP7/1.0

October 2020

Maharajpur, Gwalior (M.P.) Pin Code – 474 005

i

This page is left blank intentionally

ii

Maintenance Handbook on

MEDHA MEI633

Electronic Interlocking System

CAMTECH/S/PROJ/2020-21/SP7/1.0

October 2020

iii

Foreword

Interlocking is an integral part of Railway Signalling, by which functions in a

yard are controlled in a manner that ensures safe passage of the train through the

controlled area. Railway signalling has come a long way from un-interlocked

signalling system, mechanical and electro-mechanical interlocking to the

present day modern signalling. Electronic Interlocking (EI) is one such type of

signalling arrangement which has several advantages over Electro-Mechanical

or Conventional Panel Interlocking. The interlocking logic in the EI System is

based on software and hence any modification is easy without the need for any

wiring changes. The EI System is a processor based system which have

extensive diagnostic tests built into them. This improves the reliability of the

system and leads to minimal system down time even in case of failures.

As there are continuous improvements in technology, we need to keep pace

with the latest trends and keep ourselves updated. Medha MEI633 EI System is

an indigenously developed Electronic Interlocking system and has been

installed on a number of stations of Indian Railways and more number of

installations are likely to be added in future. CAMTECH has prepared this

handbook to get the Signal personnel acquainted with this particular system. I

am confident that this handbook apart from updating the knowledge will help

the field staff in maintenance and troubleshooting of the system.

CAMTECH Gwalior Jitendra Singh

Date: November 02, 2020 Principal Executive Director

iv

Preface

Electronic Interlocking is a microprocessor based system with interface to the

Points, Signals, Track Circuits, Axle Counters, Level Crossing Gates etc.

directly from Control Panel or through Object Controllers. Unlike Electro-

Mechanical or Relay based interlocking, the major portion comprises of

Electronic PCB Modules and has self diagnostic features. Troubleshooting of

an EI System is done with the help of various indications on front facias of

PCBs, Error codes and Maintenance terminal. To ensure flawless performance

of the system, the staff maintaining it should be aware of various modules, their

functions and troubleshooting methods.

CAMTECH has prepared this handbook to help Signal Supervisors and

Maintainers in understanding the basics of Medha MEI633 Electronic

Interlocking System. As earthing, surge protection and power supply play an

important role in the functioning of EI, relevant sections has been added in the

handbook at appropriate places.

We are sincerely thankful to Signal Directorate, RDSO, Lucknow, M/s Medha

Servo Drives Pvt. Ltd., Hyderabad and S&T personnel of Indian Railways who

helped us in preparing this handbook. Since technological upgradation and

learning is a continuous process, you may feel the need for some

addition/modification in this handbook. If so, please give your comments on

email address [email protected] or write to us at Indian Railways

Centre for Advanced Maintenance Technology, In front of Adityaz Hotel,

Airport Road, Near DD Nagar, Maharajpur, Gwalior (M.P.) 474005.

CAMTECH Gwalior Dinesh Kumar Kalame

Date: October 29, 2020 Joint Director (S&T)

mailto:[email protected]

v

Table of Contents

Foreword .................................................................................................................................. iii

Preface ...................................................................................................................................... iv

Issue of correction slips ......................................................................................................... vii

Disclaimer .............................................................................................................................. viii

Our Objective .......................................................................................................................... ix

CAMTECH Publications ........................................................................................................ x

Abbreviations .......................................................................................................................... xi

List of Figures ......................................................................................................................... xii

List of Tables ......................................................................................................................... xiv

MEDHA MEI633 Electronic Interlocking System .......................... 1

1. Introduction ................................................................................................................................. 1

1.1 Salient features ........................................................................................................................ 1

1.2 Sub-systems of MEI633 .......................................................................................................... 2

1.3 System operation ..................................................................................................................... 3

2. Functions of sub-systems ............................................................................................................ 4

3. Hardware ..................................................................................................................................... 9

3.1 Sub – Systems of Central Interlocking Unit .......................................................................... 9

3.2 Sub-Systems of Object Controller ...................................................................................... 13

3.3 Sub –Systems of Panel Processor ......................................................................................... 15

4. Functions & Indications of various cards.................................................................................. 17

4.1 Vital Interlocking Computer (VIC ) Card (CVC Card) ........................................................ 17

4.2 Communication Processor (COMP CPU) Card (CCC Card) ............................................... 18

4.3 Communication Interface (CIF) Card ................................................................................... 18

4.4 Voltage & Health Monitoring Card (CVHM ) ...................................................................... 19

4.5 IOCOM CPU Card ................................................................................................................. 20

4.7 WFM Input CPU (OCI) Card ................................................................................................. 22

4.8 WFM Output CPU (OCCO) Card ......................................................................................... 23

4.9 Fail Safe Relay Driver (ORLD) Card ..................................................................................... 24

4.10 Vital Cut Off (OVCO) Card ................................................................................................. 25

4.11 Panel Processor CPU (PPCC) card ....................................................................................... 26

4.12 PP Voltage & Health Monitoring (PVH) card ...................................................................... 27

4.13 Panel Processor Input (PIP) card .......................................................................................... 28

vi

4.14 Panel Processor Output (POP) Card ..................................................................................... 28

4.15 RS485-OFC Bi-directional converter card (Ring Modem) ................................................... 29

4.16 Power Supply (PPSA) Card (For Type A Power Supply) .................................................... 30

4.17 Power Supply (CCPSB) Card (For Type B Power Supply) ................................................. 30

4.18 Power Supply (OPSC) Card (For Type C Power Supply) .................................................... 31

5. Power Supply Arrangements .................................................................................................... 32

5.1 Power Supply Module (PS) ................................................................................................... 32

5.2 Power supply connection details ........................................................................................... 32

5.3 Power cables to be used in MEI633 Installation as per RDSO STS/ E/ TAN/ 3012 dt. 28-08-

15 .................................................................................................................................................. 32

5.4 MEI633 fuse rating particulars ......................................................................................... 33

6. MEI633 System Start Up procedure ........................................................................................ 41

6.1 Initial Checks before Start Up ................................................................................................ 41

6.2 System Power On .................................................................................................................. 42

7. Manual System Changeover ..................................................................................................... 45

8. Maintenance ................................................................................................................................ 46

8. Troubleshooting ........................................................................................................................ 48

8.1 Troubleshooting with help PCB front panel indications ......................................................... 48

8.2 MEI633 Maintenance tools program ...................................................................................... 48

8.3 Troubleshooting through Maintenance Terminal .................................................................... 48

8.4 Troubleshooting through MEI633 Fault Codes ...................................................................... 49

8.5 Trouble shooting serial communication link problems ........................................................... 50

9. Do's & Don'ts .............................................................................................................................. 53

vii

Issue of correction slips

The correction slips to be issued in future for this report will be numbered as follows:

CAMTECH/S/PROJ/2020-21/SP7/1.0# XX date .......

Where “XX” is the serial number of the concerned correction slip (starting from 01

onwards).

CORRECTION SLIPS ISSUED

Sr. No. of

Correction

Slip

Date of issue Page no. and Item

No. modified

Remarks

viii

Disclaimer

It is clarified that the information given in this handbook does not

supersede any existing provisions laid down in the Signal

Engineering Manual, Railway Board and RDSO publications. This

document is not statuary and instructions given are for the purpose

of guidance only. If at any point contradiction is observed, then

Signal Engineering Manual, Telecom Engineering Manual Railway

Board/RDSO guidelines may be referred or prevalent Zonal

Railways instructions may be followed.

ix

Our Objective

To upgrade Maintenance Technologies and Methodologies and achieve

improvement in Productivity and Performance of all Railway assets and

manpower which inter-alia would cover Reliability, Availability and

Utilisation.

If you have any suggestion & any specific comments, please write to us:

Contact person : Jt. Director (Signal & Telecommunication)

Postal Address : Centre for Advanced Maintenance Technology,

Maharajpur, Gwalior (M.P.) Pin Code – 474 005

Phone : 0751 - 2470185

Fax : 0751 – 2470841

Email : [email protected]


x

CAMTECH Publications

CAMTECH is continuing its efforts in the documentation and up-gradation of information on

maintenance practices of Signalling & Telecom assets. Over the years a large number of

publications on Signalling & Telecom subjects have been prepared in the form of handbooks,

pocket books, pamphlets and video films. These publications have been uploaded on the

internet as well as railnet.

For downloading these publications

On Internet:

Visit www.rdso.indianrailways.gov.in Go to Directorates → CAMTECH Gwalior → Other Important links → Publications for

download - S&T Engineering or click on link

https://rdso.indianrailways.gov.in/view_section.jsp?lang=0&id=0,2,17,6313,6321,6326

On Railnet:

Visit RDSO website at 10.100.2.19

Go to Directorates → CAMTECH → Publications → S&T Engineering Or click on the link

http://10.100.2.19/camtech/Publications/CAMTECH%20Publications%20Online/SntPub.htm

A limited number of publications in hard copy are also available in CAMTECH library which

can be got issued by deputing staff with official letter from controllong officer. The letter

should be addressed to Director (S&T), CAMTECH, Gwalior.

For any further information regarding publications please contact:

Director (S&T) – 0751-2470185 (O)(BSNL)

SSE/Signal - 7024141046 (CUG)

Or

Email at [email protected]

Or

FAX to 0751-2470841 (BSNL)

Or

Write at

Director (S&T)

Indian Railways Centre for Advanced Maintenance Technology,

In front of Hotel Adityaz, Airport Road, Maharajpur,

Gwalior (M.P.) 474005

http://www.rdso.indianrailways.gov.in/

https://rdso.indianrailways.gov.in/view_section.jsp?lang=0&id=0,2,17,6313,6321,6326

http://10.100.2.19/camtech/Publications/CAMTECH%20Publications%20Online/SntPub.htm


xi

Abbreviations

Abbreviation Description

AC Alternating Current

BRC Bonded Ring Configuration

CB Counter Box

CCIP Command Cum Indication Panel

CIU Central Interlocking Unit

CPU Central Processing Unit

CT Cable Termination

DB Distribution Box

DC Direct Current

DL Data Logger

EI Electronic Interlocking

EMI Electromagnetic Interference

FMC Fan Monitoring Card

FPD Front Panel Display

FTOT Field Termination Output Termination

IPS Integrated Power Supply

I/O Input/Output

LA Lightning Arrester

LED Light Emitting Diode

MEEB Main Equi-potential Earth Busbar

MT Maintenance terminal

OC Object Controller

OCM Object Controller Module

OFC Optical Fibre Communication

PC Personal Computer

PCB Printed Circuit Board

PP Panel Processor

RDSO Research Designs & Standards Organisation

SEEB Sub Equi-potential Earth Busbar

SM Station Master

SPD Surge Protection

UG Underground

USB Universal Serial Bus

VCOR Voltage Cut Off Relay

VDU CT Video Display Unit Control Terminal

xii

List of Figures

Figure 1: Two out of Two Architecture .................................................................................................... 1

Figure 2: Two out of Two System with Hot Standby ............................................................................... 2

Figure 3: MEI633 Sub Systems ................................................................................................................ 3

Figure 4: Medha MEI633 EI System Block Diagram ................................................................................ 4

Figure 5: Central Interlocking Unit .......................................................................................................... 4

Figure 6: Block diagram of Object Controller .......................................................................................... 5

Figure 7: Object Controller ...................................................................................................................... 5

Figure 8 : Control Cum Indication Panel .................................................................................................. 6

Figure 9: Panel Processor ........................................................................................................................ 6

Figure 10 : Counter Box ........................................................................................................................... 7

Figure 11 :VDU CT ................................................................................................................................... 7

Figure 12 : Front Panel Display ............................................................................................................... 8

Figure 13 : Maintenance Terminal .......................................................................................................... 8

Figure 14 : Data Logger ........................................................................................................................... 8

Figure 15 : Sub - Systems of Central Interlocking Unit ............................................................................ 9

Figure 16 : Central Interlocking Unit Bottom Bin .................................................................................. 10

Figure 18 : Front Panel Display (FPD) .................................................................................................... 11

Figure 17 : Central Interlocking Unit Top Bin ........................................................................................ 11

Figure 19 : Ports of Central Interlocking Unit ........................................................................................ 12

Figure 20: Sub - Systems of Object Controller ...................................................................................... 13

Figure 21 : Object Controller Rack Bottom Bin ..................................................................................... 14

Figure 22 : Object Controller Rack Top Bin............................................................................................ 14

Figure 23 : VCOR QN Series ................................................................................................................... 15

Figure 24 : Panel Processor Rack Bottom Bin ....................................................................................... 16

Figure 25 : Panel Processor Rack Top Bin.............................................................................................. 16

Figure 26 : VIC Card Front display ......................................................................................................... 17

Figure 27 : CCC Card Front display ........................................................................................................ 18

Figure 28: CIF Card Front display .......................................................................................................... 18

Figure 29 : CVHM Card Front display .................................................................................................... 19

Figure 30 : IOCOM Card Front display ................................................................................................... 20

Figure 31: OVH Card Front display ........................................................................................................ 21

Figure 32: OCI Card Front display.......................................................................................................... 22

Figure 33: OCCO Card front display ...................................................................................................... 23

Figure 34: ORLD Card Front display ...................................................................................................... 24

Figure 35 : OVCO Card Front display ..................................................................................................... 25

Figure 36 : PPCC Card Front display ...................................................................................................... 26

Figure 37 : PPVH Card Front display ..................................................................................................... 27

Figure 38 : PPIP Card Front display ....................................................................................................... 28

Figure 39 : PPOP Card Front display...................................................................................................... 28

Figure 40 : RS485 OFC Bi-Directional Converter Card Front display ..................................................... 29

Figure 41 : PPSA Card front display ....................................................................................................... 30

Figure 42 : CCPSB Card Front display .................................................................................................... 30

xiii

Figure 43 : OPSC Card Front display ...................................................................................................... 31

Figure 44 : Power Supply connection details for Central Interlocking Unit Module ............................ 34

Figure 45 : Power Supply connection details for Object Controller Module ......................................... 34

Figure 46 : Power Supply connection details for Object Controller Module ......................................... 35

Figure 47 : Power Supply connection details for Panel Processor Module ........................................... 35

Figure 48 : MEI633 Power Distribution for 110 V DC Supply ................................................................ 37

Figure 49 : MEI633 Power Distribution for 230 V AC Supply ................................................................. 38

Figure 50 : Medha MEI633 EI Power Supply Scheme as per RDSO Technical Advisory Note no. 3012

Ver 2.0 dt. 22.08.2016 ........................................................................................................................... 39

Figure 51: General Block diagram of Power Supply distribution of Medha MEI633 Electronic

Interlocking System ............................................................................................................................... 40

Figure 52 : Counter Box Indications ...................................................................................................... 44

Figure 53 : Manual changeover through CVHM Card ........................................................................... 45

Figure 54 : Flowchart for Medha MEI633 EI Input Relay Failure Troubleshooting ............................... 51

Figure 55 : Flowchart for Medha MEI633 EI Output Relay Failure Troubleshooting ............................ 52

xiv

List of Tables

Table 1 : Central Interlocking Unit Rack – (Bottom Bin)....................................................................... 10

Table 2: Central Interlocking Unit Rack - (Top Bin)............................................................................ 10

Table 3: Central Interlocking Unit Rack – (Front Panel Display) – 2 Nos............................................11

Table 4: Object Controller Rack – OC (Bottom Bin).............................................................................. 13

Table 5: Object Controller Rack –OC (Top Bin)..................................................................................... 14

Table 6: Panel Processor Rack – MPP (Bottom Bin)..............................................................................15

Table 7 :Panel Processor Rack – MPP (Top Bin).................................................................................... 16

Table 8: CVC Indications..................................................................................................................... 17

Table 9: CCC Indications....................................................................................................................... 18

Table 10 : CIF Indications..................................................................................................................... 18

Table 11: CVHM Indications.................................................................................................................19

Table 12 :IOCOM Indications................................................................................................................ 20

Table 13: OVH Indications.................................................................................................................... 21

Table 14: OCI Indications...................................................................................................................... 22

Table 15: OCCO Indications.................................................................................................................. 23

Table 16: ORLD Indications................................................................................................................... 24

Table 17 :OVCO Indications................................................................................................................. 25

Table 18: PPCC Indications................................................................................................................... 26

Table 19 : PPVH Indications.................................................................................................................. 27

Table 20 :PPIP Indications..................................................................................................................... 28

Table 21: PPOP Indications.................................................................................................................. 28

Table 22 : Converter Card Indications.................................................................................................. 29

Table 23 :PPSA Indications................................................................................................................... 30

Table 24 : CCPSB Indications................................................................................................................ 30

Table 25 :OPSC Indications................................................................................................................... 31

Table 26 : Power Cable particulars....................................................................................................... 32

Table 27 : Fuse ratings for Equipments................................................................................................ 33

Table 28 : Fuse ratings for Distribution Box......................................................................................... 33

Table 29 : Monthly Maintenance Schedule.......................................................................................... 46

xv


CAMTECH/S/PROJ/2020-21/SP7/1.0 1

Medha MEI633 Electronic Interlocking October 2020

MEDHA MEI633 Electronic Interlocking System

1. Introduction

MEI633 is a microprocessor based system with interface to the Points, Signals, Track

Circuits, Axle Counters, Level Crossing Gates, Ground Frames, Block Instruments for Block

working with adjacent stations, and crank handles for manual operation of Points. It has the

provision to interface with an External Data Logger through Serial Link to log events.

MEI633 is a self-contained independent system, which can be used standalone to control the

train movement in the Yard. MEI633 system conforms to RDSO Specification No.

RDSO/SPN/192/2005.

1.1 Salient features

MEI633 system can be installed as a centralized system or a distributed system.

Substantial cost savings can be achieved by using optical fibre communication cable in

place of signalling cable for distributed system.

MEI633 system implements Two-out-of-Two Hardware architecture with identical

Hardware and identical Software for Vital modules.

MEI633 provides Hot Stand-by with automatic changeover for all modules, except the

field modules.

Figure 1: Two out of Two Architecture



Figure 2: Two out of Two System with Hot Standby

The number of Object Controllers, the number of Input and Output WFMs in each OC,

and the Input and Output modules required for the Panel Processor can be selected as

per the Yard I/O requirement.

The number of Object Controllers, the number of Input and Output WFMs in each OC,

and the Input and Output modules required for the Panel Processor can be selected as

per the Yard I/O requirement.

MEI633 system operates on a cycle time basis, where the Interlocking equations are

executed every cycle. Accidental usage of stale data is avoided.

MEI633 system is capable of handling the Yards up to 350 routes.

1.2 Sub-systems of MEI633

The MEI633 comprises of the following sub-systems:

(a). Central Interlocking Unit (CIU)

(b). Object Controllers (OC)

(c). Panel Processor Unit (PP)

(d). Power Supply Module

(e). Control Cum Indication Panel (CCIP)

(f). Counter Box Module

(g). Data Logger (DL)

(h). Video Display Unit Control Terminal(VDU CT )

(i). Maintenance Terminal (MT)

(j). Front Panel Display Unit (FPD)



Figure 3: MEI633 Sub Systems

1.3 System operation

The major building blocks of MEI633 are Central Interlocking Unit (CIU), Object

Controller Modules (OCM) and Panel Processor (PP).

Cycle time of MEI633 is 333 ms.

The actual state of the yard is displayed on CCIP/VDU CT.

CIU collects the Yard information from OCMs and operator commands from PP/CCIP

/VDU CT.

CIU validates and executes interlocking equations based on the available information

from field units and received commands from CCIP/VDU CT.

The outcome of the equation execution is the OCM output data and PP/VDU CT

indication data.

OCM output data is used to drive the output relays. Driving an output relay generally

clears a signal or operates a point.

In other words, CIU generated field outputs, are transmitted to field modules, and

indication output is transmitted to PP/VDU CT.



Figure 4: Medha MEI633 EI System Block Diagram

2. Functions of sub-systems

Central Interlocking Unit (CIU)

Central Interlocking Unit (CIU) Performs the Vital Interlocking functions and Communicates

with the other Sub-Systems. It consists of VIC, COMP, CIF and VHM cards, which are

enclosed in a single box. Input data from PP/VDU CT Modules, OCMs is received by CIU.

The received input data is processed for interlocking by CIU and output data is generated

based on the input data. The respective output data is sent to PP/VDU CT Modules, Counter

Box, MT and OCMs.

Figure 5: Central Interlocking Unit



Object Controller Module (OCM)

Object Controllers acquire the Vital Field Input Data and drive the Vital Field Outputs. The

Object Controller Module (OCM) consists of two IOCOMs namely IOCOM-A, IOCOM-B

and a maximum of 8 WFMs. There can be at most 32 OCMs in a system. WFMs are

connected to IOCOM-A and IOCOM-B through RS485 interface. IOCOM-A and IOCOM-B

are connected to COMP-A and COMP-B respectively, through OFC interface. Input WFM

gets the status of the wayside functions in the yard. Output WFM receives the wayside

function output data from CIU through IOCOMs and drives the wayside functions connected

to it. Each Input WFM can read at most eight wayside function inputs and each Output WFM

can drive at most 8 wayside function outputs.

Figure 6: Block diagram of Object Controller

Figure 7: Object Controller



Command Cum Indication Panel (CCIP)

CCIP consists of Push Buttons/Knobs, Keys, LEDs and Buzzers. Push Buttons/Knobs are

used to issue commands to System. Keys on CCIP can be in, Key In/Key Out position to

enable/disable processing of the commands issued by operator to System. LEDs on CCIP

indicate the yard status e.g. colour light signal on/off status, point position and track

occupation status. Buzzers are used to indicate the Button stuck condition or signal blank

condition. CCIP is connected to PP Modules through Input and Output Cards. PP module’s

link status with CIU and its Health status are indicated on CCIP.

Figure 8 : Control Cum Indication Panel

Panel Processor (PP)

Panel Processor module consists of two Panel Processors and each is connected to a common

set of Input and Output cards through parallel interface. On the other hand, each Panel

Processor is connected to COMP through Optical Fiber Interface. Each Panel Processor scans

the state of the inputs on CCIP through Input cards, and sends the same to VICs via the

respective COMP. Each of them receives Indication Information from Active VIC and drives

the same to CCIP through output cards, providing visual indication to operator. Indication

Information represents the current Yard status.

Figure 9: Panel Processor



Power Supply Module (PS)

MEI633 uses three types of Power Supply modules viz, Type A, Type B and Type C Power

supplies. These power supplies are designed specifically to meet the requirements of various

cards in the CIU, OC and PP modules. All the three types take +24V as input.

M633PSA-01 O/p: 4.5V @ 8A --------- ( in PP )

M633PSB-01 O/p: 4.5V @ 3A --------- ( in OC & CIU , PP,CB)

M633PSC-01 Dual Output type –O/p-1: 4.5V@6A, O/p-2: 5.8V @2A (in OC)

Counter Box

Counter Box consists of CPU card and Output card. Output card is used to drive the counters

and buzzers. CPU card is connected to Output card and on the other end it is connected to

COMP-A and COMP-B, through Optical Fiber Interface. CPU card receives messages from

both COMPs. Ultimately it takes data to drive counters and buzzers from the Active COMP

channel. Counter Box module also indicates VIC-A and VIC-B status (Active, Standby and

Not Available), wrong side failure information from OC and CIU by the corresponding

LEDs.

Video Display Unit Control Terminal (VDU CT)

Video Display Unit Control Terminal (VDU CT) is a

PC based application Software. VDU CT is connected

to CIU through OFC interface. Operator can issue

commands using the simulated buttons on the VDU

CT screen. It sends the command and receives the yard

status from COMP and displays the same on the VDU

CT screen. With a redundant VDU CT arrangement,

CCIP and PP can be eliminated and thus achieving substantial

cost-effectiveness.

Figure 10 : Counter Box

Figure 11 :VDU CT



Front Panel Display (FPD)

LED Display is connected to CIU through RS232 interface. The system consists of two units,

namely Display-A and Display-B. They are used to display the system faults/recovery

messages.

Figure 12 : Front Panel Display

Maintenance Terminal (MT)

MT (Maintenance Terminal) is a PC based application

Software. MT is connected to CIU through RS232-OFC

Interface. MT screen shows the status of the system, logs the

events/faults received from CIU and generates alarm signal

if any critical fault is received from the CIU. Proprietary

serial communication protocol is used for communication

between CIU and MT. Diagnostic facility is available from

the MT in easily understandable language. Facility or replay

of recorded events through MT for offline analysis is

available.

Data Logger (DL)

Data Logger (DL) is a device connected to CIU through RS232-OFC interface. DL is used to

log the yard and system status in every cycle. Proprietary serial communication protocol is

used for communication between CIU and Data Logger.

Figure 13 : Maintenance

Terminal

Figure 14 : Data Logger



3. Hardware

The hardware for MEI633 can be divided broadly into the following three modules:

Central Interlocking Unit

Object Controller Module

Panel Processor Module

Each Module further consists of two sub-systems that are physically arranged in two separate

mechanical enclosures that can be stacked one over the other. Each sub-system is housed in

standard 19” racks (with the exception to PP which is housed in 27” rack). Each enclosure

houses individual PCBs pertaining to a logical sub-system of MEI633.

3.1 Sub – Systems of Central Interlocking Unit

Figure 15 : Sub - Systems of Central Interlocking Unit



Table 1 : Central Interlocking Unit Rack – (Bottom Bin)

PCB Name Qty Basic Function(s)

CIU Bottom Backplane 1 Mother board for the CPU, CIF and VHM cards

Vital Interlocking Computer

card (CVC card or VIC Card)

2 Performs the vital interlocking and indication

logic computation

Communication Processor

card (CCC CPU card or

COMP CPU Card)

2 Bridges the field modules and PP with the Vital

Interlocking computer through serial

interface

Communication Interface

card (CIF card)

2 CIF Card provides Isolated, Full Duplex RS485

Interface to the Communication Processor Card

in the CIU module.

CIU Voltage and Health

Monitoring card (CVHM

card)

2 Monitors the voltage and health of COMP

(CCC) and CVC (VIC) cards

Figure 16 : Central Interlocking Unit Bottom Bin

Table 2: Central Interlocking Unit Rack - (Top Bin)


CIU Top Backplane 1 Mother board for the Power supply cards

Power Supply Type B

4.5V@3A

4 To provide power to COMP CPU cards (2

no.s) and VIC cards (2 no.s)



Table 3: Central Interlocking Unit Rack – (Front Panel Display) – 2 Nos.


Front Panel Display Card 1 To display Fault codes and System status

messages received from SVP

Figure 18 : Front Panel Display (FPD)

Figure 17 : Central Interlocking Unit Top Bin



Ports Connected to CIU (For Ch-A and Ch-B each) :

CIU has 12 serial communication ports

• 8 ports are used for 32 OCMs (on each port, a max 4 OCMs can be connected)

• 1 port is used for PPs and VDUs (Max.4 PPs and/or 4 VDUs can be connected)

• 3 ports for OEIS/CTC/MSDAC/TCAS/ any ATP system

(1- port is reserved for OEIS, 1- port is reserved for CTC, 1 port remaining is used for

future use)

CIU also connected to MT, DL,CB,& FPD

Figure 19 : Ports of Central Interlocking Unit



3.2 Sub-Systems of Object Controller

Figure 20: Sub - Systems of Object Controller

Table 4: Object Controller Rack – OC (Bottom Bin)


OC Bottom Backplane 1 Mother board for the WFM cards

Input Wayside Function

Module CPU Card OCCI

(Input WFM CPU Card)

5 (Max.) Reads the status of input relays

Output Wayside Function

Module Output Card

OCCO (Output WFM CPU

Card)

3 (Max.) Drives the field output relays through

the Relay Driver card

WFM Relay Driver Card

(ORLD Card)

3 (Max.) Drives the field output relays in a fail-

safe manner

Vital Cut-off Card (OVCO

Card)

1 Monitors the health of Output WFM

CPU cards



Figure 21 : Object Controller Rack Bottom Bin

Table 5: Object Controller Rack –OC (Top Bin)


OC Top Backplane 1 Mother board for the CPU, CIF

& VHM cards

OICC - IO Communication

Processor Card (IOCOM CPU

card)

2 Transfers information between

COMP and WFMs

OPSB - Power Supply Type B

O/p: 4.5V @ 3A

2 To provide power to IOCOM

CPU cards (2 Nos.)

OPSC - Power Supply Type C

Dual O/P– O/p-1: 4.5V @ 6A

O/p-2: 5.8V @ 2A

2 To provide power to WFM

CPU cards (2 Nos.)

OVH - OC Voltage and Health

Monitoring card

2 Monitors the Voltage and

Health of IOCOM CPU card

Figure 22 : Object Controller Rack Top Bin



3.2.1 Object Controller Voltage Cut-Off Relay (VCOR)

Each OC has a Vital Cut-Off Relay (VCOR) to power Vital Output functions connected

to that OC.

Primary Negation is triggered by dropping VCOR, in case of a Wrong Side Failure. Thus

forcing all the Vital Output functions connected to that OC in to Safe State.

Secondary Negation: In cases, where VCOR is not getting dropped and still WSF

persists, CIU will shut-down and forcing safe state in whole yard.

Capacity of OC Rack

Single OC Rack can handle upto 64 I/Os

Each Card consists of 8 Bits

i.e. 5 X 8 = 40 I/Ps, 3 X 8 = 24 O/Ps, Total I/Os = 64

Twin Racks can handle 128 I/Os

i.e. 10 X 8 = 80 I/Ps, 6 X 8 = 48 O/Ps, Total I/O=128

3.3 Sub –Systems of Panel Processor

Table 6: Panel Processor Rack – MPP (Bottom Bin)


PP CPU Backplane 1 Mother board for the CPU,

PVH, PSB and PExD cards

PP CPU card 2 Scans the CCIP buttons and

drives the indication

Power Supply Type B 2 To provide power to the PP

CPU cards (2 Nos.)

PP Extender Driver Card 2 (Max.) Interface between the CPU

backplane and IO backplane

PP Voltage and Health

Monitoring card (PVH

card)

2 Monitors the Voltage and

Health of PP CPU card

Figure 23 : VCOR QN Series



Figure 24 : Panel Processor Rack Bottom Bin

Table 7 :Panel Processor Rack – MPP (Top Bin)


PP IO Backplane 4 Mother board for PExR, PP Input

and Output cards

PP Extender

Receiver Card

4 Interface between the CPU

backplane and IO backplane

PP Input Card 11 Interface card for scanning the

CCIP buttons

PP Output Card 38 Interface card for driving the

CCIP indication outputs

Power Supply

Card -A 4.5V@8A

8 To provide power to PExR, PP

Input and Output cards

Capacity of Non-Vital I/O Card - 64 bits, It can handle 672 inputs + 2400 outputs = 3072

Figure 25 : Panel Processor Rack Top Bin



4. Functions & Indications of various cards

4.1 Vital Interlocking Computer (VIC ) Card (CVC Card)

Nameplate: CVC-A and CVC-B

Functions

1. VIC card receives the inputs from OCMs, PP Modules, VDUs, OEIS, and CTC, and

sends the output to the Communication Module.

2. It performs Vital Interlocking and Indication Logic Computation and Supervisory

processor checks.

3. It has a Serial Communication Interface with MT for sending the Data Log and System

Health information.

4. It is designed as a Dual Electronic Structure based on composite fail-safety with fail-safe

comparison.

Table 8: CVC Indications

Indication/Interface Description

LED (POWER) Availability of input power to the card

Dual digit 7

segment display

Visual indication of fault-codes

LED (CYC) Cyclic activity status of SVP. Toggled every

cycle

LED (ACT) VIC is in active mode

LED (STD BY) VIC is in standby mode

LED (MRST) Provided for future use

LEDs (COM A and

COM B)

Active status of COMP A and COMP B

respectively

9 Pin D-Female

Connector (RS232)

Used for Data Logger, Maintenance Terminal

and Front Panel Display communication during

normal operation and for Application Data

download during offline mode.

Figure 26 : VIC

Card Front display



4.2 Communication Processor (COMP CPU) Card (CCC Card)

Nameplate: CCC-A and CCC-B

Functions

1. COMP CPU card transmits and receives vital data.

2. It receives vital inputs from various IOCOMs, commands from Panel

processor, slots from any other SSI (if connected) and commands

from the CTC through various serial interfaces.

3. It receives the output messages through the DPRAMs and transmits

these messages to the respective destinations.

4. Provision is provided in card for connecting to PC parallel port for

Programming and debugging interface.

Table 9: CCC Indications



Dual digit 7 segment

display

Visual indication of fault-codes

LED (CYC)

Cyclic activity status of COMP. Toggled

every cycle

LEDs (VIC A and VIC B) Active status of VIC A and VIC B

respectively

9 pin Female connector

(RS 232)

Used for Debug port & Application data

download during offline mode

4.3 Communication Interface (CIF) Card Nameplate: CIF-A and CIF-B

Functions

1. The CIF card facilitates conversion of TTL communication signals

(Tx, Rx and RTS) to RS485 signals.

2. It provides an Isolated RS485 Full Duplex communication interface

to the serial channels.

3. Each Card can support six or twelve channels depending upon the

system configuration.

4. The Rx, Tx and the RTS signals of all the channels are provided with

protection against overvoltage and surges.

5. It facilitates the COMP CPU card to check whether the CIF card is

present and is powered or not.

Table 10 : CIF Indications



Two 50 pin D type

connectors

Provides full duplex RS485 interface with

communication processor card

Figure 27 : CCC Card Front display

Figure 28: CIF Card Front display



4.4 Voltage & Health Monitoring Card (CVHM )

Nameplate: CVHM-A and CVHM-B

Functions

1. CVH Card generates Power Good signal if all the voltages are within predefined limits

2. It monitors the status of the COMP CPU and SVP CPU activities and indicates health of

CPU.

3. In case of the voltages going beyond limits or the CPU activity being not correct it shuts

down the power input to the corresponding CPU.

4. CPU Health monitoring is performed by pattern check, pattern struck, reset count, reset

struck and shunt down command.

5. LED indications are provided for Power ON, VIC Voltage within limits, VIC Health

Status, COMP Voltage within limits, COMP Health Status, VIC power cut-off and

COMP power cut-off.

Table 11: CVHM Indications


LED (POWER) (Amber) Availability of input power to the CVH card

LED (VIC VS)

Glows Green:

VIC card voltages monitored by the Power

Manager are within predefined limits

Glows Red:

Any of the VIC card voltages monitored by the

Power Manager has gone beyond limits.

LED (VIC HS)

Glows Green and starts blinking:

VIC CPU Health OK

Glows Red:

VIC CPU Health Not OK

LED (VIC CO)

Glows Green:

CPU is operating normally

Glows Red:

CPU Power is cut-off by the VHM card.

LED (COM VS)

Glows Green:

COMP voltages monitored by the Power Manager

are within predefined limits.

Glows Red:

Any of the COMP voltages monitored by the Power

Manager has gone beyond limits.

LED (COM HS)

Glows Green and starts blinking:

COMP Health OK

Glows Red:

COMP Health Not OK

LED (COM CO)

Glows Green: CPU is operating normally

Glows Red: CPU Power is cut-off by the VHM

card

Push button (VIC SD) When pressed power manager turns OFF the Power

supply to VIC card

Push button (VIC ON) When pressed power manager turns ON the Power

supply to VIC and continues to function

normally.

Push button (COM SD) When pressed power manager turns OFF the Power

supply to COMP

Push button (COM ON) When pressed power manager turns ON the Power

supply to COMP and continues to function

normally

Figure 29 : CVHM

Card Front display



4.5 IOCOM CPU Card Nameplate: OICC-A and OICC-B Functions 1. IOCOM CPU card transfers data between the Communication Processor and the

Wayside Function modules.

2. It receives the input messages from WFP and sends output messages to COMP.

3. It has provision for BDM/JTAG for connecting to PC parallel port for Programming and

debugging interface.

Table 12 :IOCOM Indications


LED (POWER) Availability of power to the card

Dual digit 7 segment display Visual indication of fault-codes

LEDs (WFP TX and WFP RX) Transmission and reception of data from

WFP’srespectively

LED (CYC) Status of cyclic activity of the CPU.

LEDs (COM TX and COM RX) Transmission and reception of data from

COMP card respectively

15 Pin Male Connector (RS485) Provides serial communication between the

OIC card and COMP card.

Figure 30 : IOCOM Card Front display



4.6 OC Voltage & Health Monitoring (OVH) Card

Nameplate: OVH-A and OVH-B

Functions

1. OVH card generates Power Good signal if all the monitoring voltages are within limits.

2. Shuts down the power input to CPU in case of the monitoring voltages going beyond

limits or the CPU activity not being correct.

3. It monitors the status of the IOCOM CPU activity and indicates the status of CPU health.

Table 13: OVH Indications


LED (POWER)

(Amber)

Availability of power to the OVH card

LED (V. STS)

Glows Green:

All the monitoring voltages are within predefined limits.

Glows Red:

Any of the monitoring voltage has gone beyond limit.

LED (H. STS)

Glows Green: IOCOM CPU Health OK

Glows Red: IOCOM CPU Health Not OK

LED (CUT. OFF)

Glows Green: Card is operating normally

Glows Red: IOCOM CPU power is cut off by OVH card.

Push Button

(RESET)

When pressed, OVH Card ON the power to the OIC card when

it is in OFF condition

Figure 31: OVH Card Front display



4.7 WFM Input CPU (OCI) Card

Nameplate: OCCI-1, OCCI-2, OCCI-3, OCCI-4 and OCCI-5

Functions

1. OCI Card scans the state of the input relays.

2. It frames the input data based on the state of the connected input relays. The framed

input data is sent to IOCOM when they requested.

3. It indicates Input Relay connect status which is a Yard specific configuration setting.

Table 14: OCI Indications


LED (POWER) (Amber) Availability of power to the card

LEDs (B TX1 and B TX0)

(Amber blinking)

Slave CPU status of communication with IOCOM-B

CPU and IOCOM-A CPU respectively.

LED (B STS) (Green blinking) Status of cyclic activity of the Slave CPU

LED (A STS) (Green blinking) Status of cyclic activity of the Master CPU

LEDs (A TX1 and A TX0)

(Amber blinking)

Master CPU status of communication with IOCOM-

B, CPU and IOCOM-A CPU respectively

LEDs (IP1 to IP8)

(Relay Picked up -Green)

Relay Dropped - Not glowing)

Input Relay State (Picked Up/Dropped)

Figure 32: OCI Card Front display



4.8 WFM Output CPU (OCCO) Card

Nameplate: OCCO-1, OCCO-2 and OCCO-3

Functions

1. OCCO card receives Output relay drive data from IOCOMs

and drives the relays.

2. It reads the Output Relay contact states to know whether the

Output relays are in their commanded state.

3. It sends the read back data to IOCOMs.

4. It indicates Input Relay connect status which is a Yard

specific configuration setting.

5. It performs self-test at power ON to detect any possible

errors.

Table 15: OCCO Indications


LED (POWER) (Amber) Availability of power to the card

LEDs (B TX1 and B TX0)

(Amber blinking)

Slave CPU status of communication with IOCOM-B CPU

and IOCOM-A CPU respectively.

LED (B STS) (Green blinking) Status of cyclic activity of the Slave CPU

LED (A STS) (Green blinking) Status of cyclic activity of the Master CPU

LEDs (A TX1 and A TX0)

(Amber blinking)

Master CPU status of communication with IOCOM-B CPU

and IOCOM-A CPU respectively.

Figure 33: OCCO Card front display



4.9 Fail Safe Relay Driver (ORLD) Card

Nameplate: ORLD-1, ORLD-2 and ORLD-3

Functions

1. It can drive 8 External QN Type Fail-Safe Relays.

2. When the relay is to be driven it supplies 24V to the

external relays.

3. It has reverse voltage, high voltage protection and

against shorting of the drive signal.

4. Power input from two external power supplies for

redundancy.(Provided from the power supply cards)

5. Optical isolation is provided by Opto-couplers and

Galvanic isolation by transformers between the WFM

and external relays.

Table 16: ORLD Indications


LED (POWER) (Red) Availability of vital power to the relays

LEDs (OP1 - OP8)

Drive status of the eight relays

Glows Orange:

Relay connected to that particular section is driven

Glows Red:

Drive signal is present but the relay is not driven as the fuse is

blown due to over load condition

Glows Green:

External feed to the Relay during the fuse blown out condition

Figure 34: ORLD Card Front display



4.10 Vital Cut Off (OVCO) Card

Nameplate: OVCO

Functions

1. OVC card monitors the voltage outputs (+3.3 V) of the

regulators on the WFP Output CPU cards and indicates

whether the voltages are within permissible limits.

2. It monitors the status of the Output WFP CPU activity and

indicate the CPU health status.

3. It shuts down the power to the external relays in case of the

voltages going beyond limits or the CPU activity not being

correct.

4. Power Input +24 V DC (On board DC-DC Converter

generates the required voltages.

Table 17 :OVCO Indications


LED (POWER)

(Amber)

Availability of input power to the

Vital Cut-off card.

LED (VCOR)

(Amber)

Vital Cut-off relay is being driven

by the CPLDs

LED (STS A)

(Green blinking)

Starts Blinking:

All the ‘A’ CPUs sends correct

status pattern and the

status of all the ‘A’ CPUs is OK

LED (STS B)

(Green blinking)

Starts Blinking:

All the ‘B’ CPUs sends correct

status pattern and the

status of all the ‘B’ CPUs is OK

LEDs (OP1 to OP3)

(Green)

They are driven by CPLD B and

represent the connect

status of Output WFM card 1, 2 and

3.

LED (VCOR

POWER)

VCOR drive power is available to

OVC card.

Figure 35 : OVCO

Card Front display



4.11 Panel Processor CPU (PPCC) card

Nameplate: PPCC-A and PPCC-B

Functions

1. PCC card scans the state of the buttons on CCIP and sends the same to COMP.

2. It receives the indication data from COMP and drives the indication LEDs on the

Command cum Indication Panel.

3. Provision for BDM/JTAG is provided for connecting to PC parallel port for

Programming and debugging interface.

Table 18: PPCC Indications


LED (POWER) Availability of the power to the card

Dual digit 7-

segment display

Visual indication of fault codes

LED (CYC)

Status of cyclic activity of the CPU

LED (OE)

Reception of Password from the COMP for

driving the output cards

LEDs (COM Rx

and COM Tx)

Status of communication with COMP

15 pin Female

connector

(RS232)

Provides external communication interfaces

for serial ports with RS232 levels

15 pin Male

connector

(RS485)

Provides RS485 communication interface

with RS485-OFC Bi-directional converter

Figure 36 :

PPCC Card

Front display



4.12 PP Voltage & Health Monitoring (PVH) card

Nameplate: PPVH-A and PPVH-B

Functions

1. PVH card generates Power Good signal if all the monitoring

voltages are within limits.

2. It monitors the status of the PP CPU activity and indicates the

CPU health status.

3. It shuts down the power input to the CPU in case of the

voltages going beyond limits or the CPU activity being not

correct.

Table 19 : PPVH Indications


LED (POWER) Availability of input power to the PVH card

LED (V.STS)

Glows Green: All the voltages monitored by the Power

Manager are within limits

Glows Red: Any of the voltage monitored by the Power

Manager has gone beyond limit.

Third LED (H.STS)

Glows Green: PP CPU Health OK

Glows Red: PP CPU Health Not OK

Fourth LED

(Cut Off)

Glows Green: CPU is operating normally

Glows Red: CPU Power is cut-off by the VHM card

Push-button switch

(RESET)

When pressed, VHM card restarts the PP CPU card when it is

in Power OFF condition.

Figure 37 : PPVH Card Front display



4.13 Panel Processor Input (PIP) card

Nameplate: PPIP-1

Functions

1. PIP card

2. facilitates the scanning of the buttons on the CCIP by the PP

CPU card.

3. It has a provision to interface with two PP CPU cards at the same

time.

4. Maximum of 64 PIP cards can be accommodated in a system.

Table 20 :PPIP Indications



Two 37 pin D-Male

Connectors


for 64 inputs coming from the CCIP

4.14 Panel Processor Output (POP) Card

Nameplate: PPOP-1

Functions

1. POP card facilitates the driving of indication outputs on the

CCIP by the PP CPU card.

2. It has a provision to interface with two PP CPU cards at the

same time but drives the CCIP indications with the data sent by

only one CPU card at any instant of time.

3. Maximum of 64 Output cards can be accommodated in a

system.

Table 21: PPOP Indications



Two 37 pin D-Male

Connectors


for 64 inputs coming from the CCIP

Figure 38 : PPIP Card Front display

Figure 39 : PPOP Card Front display



4.15 RS485-OFC Bi-directional converter card (Ring Modem)

Table 22 : Converter Card Indications


LED (POWER) (Amber)

Availability of input power to CPLD / OFC section of the

card

LED (POWER) (Amber)

Availability of input power to RS485 section of the card

LED (PTX) (Amber blinking) Data transmitting through primary channel

LED (PRX) (Green blinking) Data receiving on primary channel

LED (STX) (Amber blinking) Data transmitting through secondary channel

LED (SRX) (Green blinking) Data receiving on secondary channel

LED (M/S) ON (Green)- The Card is programmed for Master.

OFF (Blank) - The Card is programmed for Slave.

LED (P/S) ON (Green)- The Card is using primary channel for

communication.

OFF (Blank) - The Card is using secondary channel for

communication

Figure 40 : RS485 OFC Bi-Directional Converter Card Front display



4.16 Power Supply (PPSA) Card (For Type A Power Supply)

Nameplate: PPSA1 and PPSA-2

Functions

1. PPSA card provides an output +4.5V with a capacity of

delivering up to 8Amps of current.

2. The output voltage is used to operate Input and Output cards in

Panel Processor Module.

3. The input of the card is provided with under voltage, over

voltage and reverse polarity protections.

4. The output of the card is provided with under voltage, over

voltage and over load protections.

Table 23 :PPSA Indications


LED (24 V) (Amber) Availability of power to the

card

LED (ERROR) (Red if not

blank)

Power supply Input out of

limits

LED (4.5V) (Green) 4.5V Output voltage OK

4.17 Power Supply (CCPSB) Card (For Type B Power Supply)

Nameplate: CCPSB-A, CCPSB-B, CVPSB-A, CVPSB-B, OPSB-A, OPSB-B, PPSB-A and

PPSB-B

Functions

1. PSB card provides an output +4.5V with a capacity of delivering up to

3Amps of current.

2. The output voltage is used to operate CIU cards, IOCOM cards and PP

cards.

3. The input of the card is provided with under voltage, over voltage and

reverse polarity protections.

4. The output of the card is provided with over voltage and over load

protections.

Table 24 : CCPSB Indications


LED (24 V) (Amber) Availability of power to the card

LED (ERROR)

(Red if not blank)

Power supply Input out of limits

LED (4.5V) (Green) 4.5V Output voltage OK

Figure 41 : PPSA Card front display

Figure 42 : CCPSB Card Front display



4.18 Power Supply (OPSC) Card (For Type C Power Supply)

Nameplate: OPSC1 and OPSC2

Functions

1. PSC card provides an output voltage of +4.5V @ 6A and +5.8

@ 2A which are isolated form earth.

2. The output voltage is used for the operation of the CPU and

Relay driver cards in the OC Module.

3. The input of the card is provided with under voltage, over

voltage and Reverse polarity protections.

4. The output of the card is provided with over voltage and short

circuit protections.

Table 25 :OPSC Indications


LED (POWER)

(Amber)

Availability of power to the card

LED (ERROR)

(Red if not blank)

Power supply Input out of limits

LED (5.8V) (Green)

5.8V Output voltage OK

LED (4.5V) (Green)

4.5V Output voltage OK

Figure 43 : OPSC Card Front display



5. Power Supply Arrangements

Each of the modules of MEI633 namely, Central Interlocking Unit, Object Controller and the

Panel Processor, are provided with two independent sources of power. One of them is used to

power the Section-A PCBs and the other is used to power the Section-B PCBs of the

modules.For the PCBs that are common to both Section-A and Section-B, the two powers are

ORed with Diodes and fed to them.

5.1 Power Supply Module (PS)

MEI633 uses three types of Power Supply modules viz, Type A, Type B and Type C Power

supplies. These power supplies are designed specifically to meet the requirements of various

cards in the CIU, OC and PP modules. All the three types take +24V as input. Power supply

Type A (M633PSA-01) is used to power the Input and Output cards of the PP module and is

rated at 4.5V@8A. Type B Power supplies (M633PSB-01) are used to provide power to the

VIC, COMP, PP CPU and IOCOM cards and are rated at 4.5V@3A. Type C Power supplies

(M633PSC-01) are dual output type and are used to provide power to the Input and Output

WFM CPU cards and are rated at 4.5V@6A, 56.8V@2A.

5.2 Power supply connection details

The external power cables are terminated on to WAGO connectors mounted on the rear side

of the modules. Then they are distributed among different PCBs using WAGO connectors

with inbuilt fuse. Before the power is fed to any PCB, it is filtered using an EMI filter to

suppress the effects of EMI, noise and surges on the power input.

5.3 Power cables to be used in MEI633 Installation as per RDSO STS/ E/ TAN/

3012 dt. 28-08-15

Table 26 : Power Cable particulars Sr.

No.

Wire Cable used Wire Guage Wire Colour Code

1 Power from Main IPS 16 sq. mm Red & Black

2 230 V AC 10 sq. mm Red & Black

3 Relay rack power 110 V

AC & 110 V DC

10 sq. mm Red & Black

4 IPS to DB Equipment 4.0 sq. mm Red & Black

5 For looping inside IPS

(use Finolex cable)

4.0 sq. mm Red & Black

6 For relay rack looping 1.5 sq. mm Red & Black

7 I/O Wiring (From OC to

Relay and RR to CT Rack

/FTOT

0.5 sq. mm Red & Black (Coil) (Relay Drive)

O/P Read (Yellow& Brown)

Input Read (Orange & Blue)

8 If station master room is in

other building

UG Cable to be

used along with

Redundant Path

9 Earthing equipment 10 sq. mm Yellow/Green, Green

10 IPS, CT RACK TO BRC 16 sq. mm Black or Yellow/Green

11 Earthing & LA 35 sq. mm Black or Yellow/Green



5.4 MEI633 fuse rating particulars

Table 27 : Fuse ratings for Equipments Sr.

No.

Equipment Provided for Fuse ratings Remarks

1 CIU Channel –A Channel

– B

4 Amps

2 Object Controller Channel –A Channel

– B

4 Amps

VCOR 4 Amps

3 Panel Processor Channel –A Channel

– B

4 Amps

4 SM Panel

Indication Power

CCIP IND Power 6 Amps at PP

10 Amps at PP @ more than 10

O/P Cards

5 SM Panel Buttons, Knobs,

System Indications

4 Amps at SM

Panel

6 FMC (Fan

Monitoring Card)

CIU, OC & PP 2 Amps

7 Counter & Buzzers Panel for Counters &

Buzzers

250 mA

Table 28 : Fuse ratings for Distribution Box Sr.

No.

DB/Room Provided for Fuse ratings Remarks

1 SER DB SSI-A, SSI-B, SSI -

INT, SSI-EXT

20 Amps Knife

Edge Fuses

@ 0 to 5 No of

OC’s

PSR Room Distribution Box 10 Amps Knife

Edge Fuses

2 DB SSI-A, SSI-B, SSI -

INT, SSI-EXT

32 Amps Knife

Edge Fuses

@ 6 to 11 No of

OC’s

PSR Room Distribution Box 16 Amps Knife

Edge Fuses

3 SER DB SSI-A, SSI-B, SSI -

INT, SSI-EXT

63 Amps Knife

Edge Fuses

Above 12 No of

OC’s

4 PSR Room Distribution Box 32 Amps Knife

Edge Fuses

Note : Before providing the final rating of rated fuses once check the Current with Clamp meter and

provide the Fuse.

The following figures provide information about the power supply connection details for each

module:



Figure 44 : Power Supply connection details for Central Interlocking Unit Module

Figure 45 : Power Supply connection details for Object Controller Module



Figure 46 : Power Supply connection details for Object Controller Module

Figure 47 : Power Supply connection details for Panel Processor Module






Figure 48 : MEI633 Power Distribution for 110 V DC Supply



Figure 49 : MEI633 Power Distribution for 230 V AC Supply



Figure 50 : Medha MEI633 EI Power Supply Scheme as per RDSO Technical Advisory Note no. 3012 Ver 2.0 dt. 22.08.2016



Figure 51: General Block diagram of Power Supply distribution of Medha MEI633 Electronic Interlocking System



6. MEI633 System Start Up procedure

After configuring and installing MEI 633, the next step in the start up process is to apply

power to the system, and then verify that the internal functions of the MEI 633 system are

working properly.

6.1 Initial Checks before Start Up

(i) The glass doors of each rack should be in locked position.

(ii) The connectors of the cable connecting different modules are fixed properly.

(iii) No loose wires are hanging from any of the PCBs.

(iv) All the indications on the facias of all the PCBs are in OFF condition.

(v) No PCB is projecting outside.

(vi) On the CCIP, the Panel/PC key should be in “Panel” position and if the particular yard

is provided with VDU also, the key can be in any position.

(vii) No indication on CCIP should be ON.

(viii) For Station with Dual VDU, ensure changeover box SM key should be IN, the Knob

position should be in Position 1 or Position 2.

(ix) No Indication on the changeover box should be ON .

(x) Ensure following before switching on the system:

All the earthing connections are made properly and connected to the equipment .

(B+C) SPD provided at the main entry level at 110VDC Distribution Box.

D Type SPD provided at 24 V DC Distribution Box.

63 Amp Fuse Available at entry level of 110 V DC.

Appropriate rated Fuse provided at 110 V DC Distribution box as per load .

4 Amp fuses available at system side.

6 Amp fuses available at Internal supply (VCOR).

2 amp fuses available at Relay rack side.

Appropriate 250 Milli Amp fuse is available at counter and buzzers.

110 V DC is isolated from other AC supply

DL have its own battery supply and wiring have a separated path .

USB ports are disabled (sealing of USB port )



6.2 System Power On

The following Switch-ON sequence should be followed for starting MEI 633:

A. Centralized System

110 V DC Mains Switch ON (in the IPS room) for powering the central cabin modules.

B. Distributed System

110 V DC Mains Switch ON (in the IPS room) for powering the End Cabin A. (Distributed

system).

110 V DC Mains Switch ON (in the IPS room) for powering the End Cabin B. (Distributed

system).

Procedure for power ON is given below in tabular form.

If Fuse is provided If Isolator 63 Amps is provided

Insert SSI relay INT Fuse Switch ON SSI-INT

Insert SSI CH A Fuse wait1 min then Switch ON SSI-CHA

Insert SSI CH B Fuse Switch ON SSI-CH B

Indications on Start Up

(a) CIU The Power ON LEDs on all the modules of CIU will be ON followed by display of Name of

the Yard on both the FPDs.

The VIC A, VIC B, COMP A and COMP B cards will be ON in sequence.

(b) OC

After power on, VHM, OCI, OCO and RS485-OFC Bidirectional converter cards will be ON.

After checking health of IOCOM cards, VCOR picks up.

When VCOR picks up, all the available ORD cards will become ON.

(c) PP/ CCIP Either of PANEL or PC LEDs will be ON depending upon PANEL/PC key position.

After the communication with COMP CPU is established, the indications on the CCIP will

reflect the actual field conditions – Signals, Points, Track Circuits etc.

(d) Dual VDU

Changeover Box LED will be ON, based on the position of the knob.

PC monitor (VDU-1 and VDU-2 )will display the yard status.

(e) Counter box

Indication is provided to the Operator for the following Critical faults on the Counter Box

Front Facia:

(i) Wrong Side failure Detection by the System

Red LED accompanied with a Fault Alarm.



CIU SHDN (CIU Shutdown) – If the Wrong side failure is detected by CIU.

OC SHDN (OC Shutdown) – If the Wrong Side failure is detected by OC.

Fault Alarm and Indication persists till the Fault is acknowledged by WSF ACK Button.

(ii) Change in the CVC Status

Indications for CVC (CVC-A and CVC-B) Status:

ACT (Active) – Green LED

STBY (Standby) – Yellow LED

NA (Not Available) – Red LED

Any change in the CVC status is indicated by an Alarm to the Operator.

The Fault Alarm persists till the Fault is acknowledged by CO ACK Button.

(iii) Panel Blank

CCIP is blank and no Route / Signal indication is shown, then

Either Panel Power Supply is faulty.

Or Communication from CIU is faulty from both the channels.

If all the indications on the CCIP are OFF, the Panel Power supply is faulty.

If the Link Status Faulty indication is displayed for both the channels, it indicates that

both the communication channels are faulty.

(iv) Link Status Indication

When Channel A or Channel B link is available, corresponding yellow indication will be

flashing continuously.

When Channel A or Channel B link is faulty, corresponding red indication will be


When both the communication channels are faulty, Link Status Faulty indication is

displayed for both channels.

Buzzer and Acknowledgement When Channel A link or Channel B Link fails, a Buzzer is turned on to alert the operator.

The Buzzer is stopped by pressing the Acknowledge button. The Maintenance staff is

informed take appropriate action to rectify the fault.



Figure 52 : Counter Box Indications

(v) Health Status Indication

When Channel A or Channel B health is good, corresponding yellow indication will be


When Channel A or Channel B health is faulty, corresponding red indication will be


Buzzer and Acknowledgement

When Channel A Health or Channel B Health is failed, a buzzer is turned on to alert the

operator. To acknowledge the fault, press the Acknowledge button. The buzzer stops

when the fault is acknowledged by operator.



7. Manual System Changeover

Ensure there is no train movement in the yard.

Ensure that no signal operation is being done by the SM

To do the changeover from Normal system to Standby system – Press “VIC SD button”

on the fascia of the CVHM card of Active channel as indicated in Figure 53.

Use Change over (COR) tool to press the VIC SD button. (do not use excessive force to

press the button).

Then press the COM SD button on the fascia of CVHM card using the COR tool as

indicated in the figure. (do not use excessive force to press the button).

After above operation, Active system will shut down and Stand by system will become

Active.

To restore power of CVC & CCC cards, VIC ON & COM ON buttons should be pressed

respectively.

After Power ON wait until Standby LED of CVC card is ON or standby message is

displayed on MT screen.

Note:

Until Stand by Indication is available on CVC card, No other change over is permitted.

If Active card is shutdown during this period, the complete system will shut down

immediately.

Press VIC SD Button

Press VIC ON Button

Press COM SD Button

Press COM ON Button

Figure 53 : Manual changeover through CVHM Card



8. Maintenance

Maintenance personnel must be familiar with the recommended methods for operating,

testing, and repairing the MEI633 system equipment.

Periodically check the Battery for the electrolyte level & top up if necessary.

Check the SPD devices for any signs of physical degradation.

Ensure Maintenance Terminal data is backed up during maintenance schedules.

Ensure that MT PC/ VDU is always ON and communication link is working for both A

& B channels. Also ensure that time is in Sync. with Data Logger time.

Adequate quantities of spare cards should be kept in the station to handle any situation

that calls for replacement of the cards. The spare cards to be periodically checked and

verified for correct functional.

Earthing for the installation should be checked once in every six months and regular

maintenance activities should be carried out.

Table 29 : Monthly Maintenance Schedule Sr.

No.

Location Description Action Taken/

Note the Voltage

levels

Observations Remarks

1 MT PC Backup the MT data logs Both channels

Event and Fault

logs data

downloading

should be done

Ensure the MT PC is

always ON and

communication link is

working for both A & B

channels; Also ensure

time is in Sync. With DL

time

2 DL PC Ensure DL is always ON

and Data is backed up

3 IPS Room Check the Voltage levels

at 230V IPS Mains Input

voltage to FRBC modules

150V to 275V If Medha

full IPS is

provided 4 Battery

Room

Measuring Cell, Battery

voltage & specific

Gravity

level maintenance as per

Railways Battery

checklist

Battery bank

fully charged

condition should

be 110V & SG

level 1190 to

1220

If Medha

full IPS is

provided.

Switch off

Mains and

take the

readings

5 Equipment / Clean the Dust filters, To be free from



Sr.

No.


Note the Voltage

levels


Relay Room Exhaust fan filters as well

as fans

dust

Clean the EI Equipments To be free from

dust

Check the ommunication

status of the EI Modules

and Ring Modems

Relevant

Communication

and LEDs should

Glow/Blink

Check all Health Status

LEDs,i.e System health

Indication, Output

Voltage Indication of

system and VCOR power

LED indication

LEDs should

Glow/Blink

Check the voltages at

Equipment End of Ch-A

& Ch-B

23V to 24.5V to

be observed


Equipment End of

INTERNAL

22V to 24V to be

observed


Equipment End of

EXTERNAL (FMC)

22V to 24V to be

observed

Check the Panel

Indication Power voltages

at Equipment End

19V to 21V to be

observed

Visually examine all the

S/A cards are locked &

Inserted properly, tighten

the corresponding screws

Ensure the

tightness of the

cards

Check the all wago fuse

indications

Disconnect type

fuse indications

should not glow

6 Earthing,

LA & SPD

Clean surface of the Earth

Electrode /MEEB /SEEB

/BRC

Surface should be

kept clean

Measure the Earth

Resistance of the

each Earth Pit &Ring

Earth Resistance. Fill

water in the Earth Pits to

keep low soil resistance

Should be <1Ώ

(Ohm)

Check the SPD devices

for any signs of physical

degradation

Check the

Indication LED

status of SPD

Check Lightning Arrestor



Sr.

No.


Note the Voltage

levels


connection at copper wire

to Ring earth. Tighten all

the connections

/Terminations

8. Troubleshooting

Troubleshooting of MEI633 system can be done in following ways:

8.1 Troubleshooting with help PCB front panel indications

The front facia of all the MEI633 system printed circuit boards are provided with LED

indications. These indications assist the operator to know the status of the card at any point of

time. These indications may help the maintainer in troubleshooting upto some extent. The

details of these indications are provided in section.

8.2 MEI633 Maintenance tools program

Maintenance engineers and application engineers use MEI633 Maintenance Terminal (MT)

to view and monitor Events/Relay status and MEI633 system faults. MT provide wide range

of options:

Viewing the current status (On line data) of the MEI633 system.

Reviewing stored system event and error data (Off line data).

Cautions when any fault occurs in the system so as to take necessary action.

Shows faults and critical faults in both Channel-A and Channel-B

8.3 Troubleshooting through Maintenance Terminal

CIU logs the generated events and fault codes in external flash memory in every cycle. It

transmits event log to Data logger, fault information to FPD, and both event, fault

information to MT.

GIU based MT is developed as a user-friendly application providing hassle-free interface,

thus making the life easy for the Maintainer to pinpoint the problems during troubleshooting.

MT is a password-protected application, where unauthorized access is not allowed.

The Event log/Fault analysis can be performed over a required time frame, chosen by the

maintenance staff. Print facility is also available.

The Playback feature of MT provides the Operator/Maintainer to visualize the Yard status

over a required time frame and thus making the analysis easier.



Fault messages are in simple English and greatly help to pinpoint the error location within the

shortest time frame.

Example:

A) If the communication messages from IOCOM0 to COMP are corrupted – Fault code

displayed on MT is “Channel Noisy – IOCOM0”

B) If the communication messages from IOCOM0 to COMP are not available – Fault code

displayed on MT is “Link Fail – IOCOM0”

C) If the position of the Point18 in the field is undetermined - Fault code displayed on MT is

“Point Detection Failed – PT18”

D) If HR Relay of Signal1 is picked up unintentionally, a wrong side failure is indicated

along with safety action – Fault code displayed on MT is “HR Wrong Side Fail – SIG1”

8.4 Troubleshooting through MEI633 Fault Codes

Troubleshooting the MEI633 system involves careful analysis of observable fault codes

displayed on Maintenance Terminal tool program and front panel display, and the ability to

perform standard electrical and electronic troubleshooting operations.

System event log information associated with different modules of MEI633 are captured in

Maintenance terminal tool program contain great deal of historical information regarding the

performance of MEI633. These event logs are useful while troubleshooting. The information

placed in the event logs contain Fault Codes, which are categorized into Critical and Non

Critical Faults.

The Critical Faults are the Faults, which may cause Restart or Shutdown of the Faulty

module, or they indicate a serious error, which needs immediate attention.

The Maintainer is alerted about the Critical Fault by a Fault Buzzer in the Front Panel

Display and also in the Maintenance Terminal, if it is connected to the System.

Non Critical Faults are the faults, which do not cause the System to restart, or shutdown, but

the System may continue to operate through the other redundant channel or in a de-graded

mode of operation.



8.5 Trouble shooting serial communication link problems

Serial link to MT

When no event logs are displayed on the MT then check the serial cable connecting MT to

CVC card of MEI633. Insert the cable properly on either end of the cable. If cable ends are

properly inserted even logs will be displayed in MT. Even after inserting the cable properly if

event logs are not displayed then replace the cable.

Serial link to Front panel display

When Link Failed message is displayed on front panel, check for serial cable connecting

ISO232 card. If the cable is found faulty replace the cable. When status is not displayed

check for power supply LED on the front panel display. If power supply LED doesn’t glow

then check power supply connection cable and take necessary action.

Serial link to VDU

When Yard is not displayed on VDU PC check for serial cable connecting RS232-OFC card.

If the cable is found faulty replace the cable.

After the cause of the malfunction has been isolated to either the serial communication link

problem or a single line replaceable hardware item, the next step is to make corrective repairs

and restore the system to normal operation.

If the malfunction has been traced to a hardware component, replace the card and make the

necessary repairs as per fault code tables.

If the malfunction appears to be related to the application program, review the program

listing carefully, make any necessary corrections, recompile the program, and then reload the

program as per Service manual System manual covering the application programming of the

MEI633 system. After the application software has been reloaded, check the configuration of

the affected portion of the system as per MEI System configuration guidelines. Then retest

the affected system functions to verify proper operation.



Figure 54 : Flowchart for Medha MEI633 EI Input Relay Failure Troubleshooting



Figure 55 : Flowchart for Medha MEI633 EI Output Relay Failure Troubleshooting



9. Do's & Don'ts

Do's

Keep the EI Room free from dust.

Maintain minimum 25V-27V at Distribution Box in EI IPS Room.

Check the EI system fuses at regular intervals for proper contact.

Check the SPD health indication i.e. whether indication glowing or not in EI-Relay room

and EI-IPS Room periodically.

Ensure Maintenance Terminal PC is always ON and verify the Event Data Log updates.

Periodically change over to STANDBY system by shutting down the ACTIVE system

quarterly as per prescribed changeover procedure.

Periodically check the tightness for the earth connections at MEEB, SEEB and all pin

earth points.

Clean externally accumulated dust in EI equipment with soft with soft cloth/brush.

Periodically check the battery for the electrolyte level and makeup if necessary.

In case of testing is required, it shall be done by trained personnel when the yard is free

from movement or occupancy.

Don't

Try to troubleshoot without MEI633 training.

Use Walkie Talkie, Mobile phone or any radio equipment near EI equipment.

Switch off any of the EI-IPS Modules when EI is in operation.

Remove Modules, Fuses, or Connectors when EI is in operation.

Forcibly pick up any Relay/Relays in EI room/Field

Remove any EI Relay/Relays.

Change Jumper settings/Application Data without prior approval.

Disturb OFC cable or connector.

Switch OFF MT-PC/Loading any software/Files.

Use Removable media/USB/DVD/CD in VDU and MT PCs.

Try to do system changeover without following System Changeover procedure

Perform changeover before standby LED indication is available on CVC card or before

standby message is displayed on MT screen.

Touch the board components / Repair on your own.




Quality Policy

“We at RDSO Lucknow are committed to maintain and update

transparent standards of services to develop safe, modern and cost

effective railway technology complying with statutory and regulatory

requirements, through excellence in research, designs and standards by

setting quality objectives, commitment to satisfy applicable requirements

and continual improvements of the quality management system to cater

to growing needs, demand and expectations of passenger and freight

traffic on the railways through periodic review of quality management

systems to achieve continual improvement and customer appreciation. It

is communicated and applied within the organization and making it

available to all the relevant interested parties.”

INDIAN RAILWAYS Centre for Advanced Maintenance Technology Maharajpur, Gwalior (M.P.) Pin Code – 474 005

Documents

GOVERNMENT OF INDIA MINISTRY OF RAILWAYS ......Medha MEI633 EI System is an indigenously developed Electronic Interlocking system and has been installed on a number of stations of