Memshield - ACB Ratings & Speciﬁcations Air Circuit Breakers · Memshield Memshield - ACB Ratings & Speciﬁcations Air Circuit ... BB B B B B B 0.05 0.05 0.05 0.05 ... A B (3P)

Memshield - ACB Ratings & SpecificationsMemshield Air CircuitBreakers

8

Rating and specifications

630 1250 1600 2000 2500 3200 4000

MACB06 MACB12 MACB16 MACB20 MACB25 MACB32 MACB40

Current rating, A

List No

9

1

666

NOTES:1

8

7

9

10

3

:Values in open air at 40°C (45°C for marine applications). :For vertical terminals, d = 92 mm.:DC rating is for special application. For further details, contact MEM Ltd. (500V) :Rated operational voltage depends on applied standard: 690V according to IEC947-2:Approval pending. :Only applied to 3 pole ACBs.:Full rated neutral pole available on request. :Rated insulation voltage depends on applied standard: 1000VAC according to IEC947-2

:The application of I.T. systems at this voltage is not permissible6

5

a c d

d

b

b

a 20

20

c

IEC 947-2BS EN 60947-2CEI EN 60947-2

3 4 3 4 3 4 3 4 3 4 3 4 3 4630 1250 1600 2000 2500 3200 4000630 1250 1600 2000 2000 2000 200080 320 320 320 250 1600 4000160 630 630 630 500 3200320 1250 1250 1250 1000630 1600 1600 2000

2000 250040£Io£80 160£Io£320 160£Io£320 160£Io£320 125£Io£250 800£Io£1600 2000£Io£400080<Io£160 320<Io£630 320<Io£630 320<Io£630 250<Io£500 1600<Io£3200160<Io£320 630<Io£1250 630<Io£1250 630<Io£1250 500<Io£1000320<Io£630 800£Io£1600 800£Io£1600 1000<Io£2000

1000£Io£2000 1250£Io£2500

8 8 8 8 8 8 81000 1000 1000 1000 1000 1000 1000690 690 690 690 690 690 690

22/46.2 50/105 50/105 50/105 50/105 50/105 50/10530/63 50/105 50/105 50/105 50/105 65/143 65/14335/73.5 65/143 65/143 65/143 65/143 85/187 85/18735/73.5 65/143 65/143 65/143 65/143 85/187 85/18722/46.2 50/105 50/105 50/105 50/105 50/105 50/10530/63 50/105 50/105 50/105 50/105 65/143 65/14335/73.5 50/105 50/105 50/105 65/143 80/176 80/17640/40 40/40 40/40 40/40 40/40 40/40 40/40– – – – – – –– – – – – – –35/73.5 65/143 65/143 65/143 65/143 91/215 85/187– – – – – – –22.2/59.4 35.2/81 35.1/81 – 45.3/106 45.4/106 –30.4/76 50.5/126 50.6/126 – 50.2/126 66.1/168 –37/90.2 72.6/190.5 72.4/190.5 67.2/144.3 72.4/190.5 91/215.1 –35/81.1 50/114.6 50/114.2 50/122.5 50/126 65/157.1 –– – – – – – –– – – – – – –35/77.2 65/145 65/145 65/145 65/145 85/203 –35/77.2 50/111 50/111 50/111 50/111 65/145 –22/59.4 35/81 35/81 35/81 45/106 45/106 –30/76 50/126 50/126 50/126 50/126 65/168 –35/90.2 65/190.5 65/190.5 65/190.5 65/190.5 65/190.5 –– – – – – – –– – – – – – –– – – – – – –35/85.4 65/148.5 65/148.5 65/148.5 65/148.5 85/220.6 –35/85.4 50/122.23 50/119.95 50/116.2 50/130.95 65/162.37 –35 50 50 50 65 80 8030 45 45 50 50 65 6535 50 50 50 50 65 65B B B B B B B

0.05 0.05 0.05 0.05 0.05 0.05 0.0510 10 10 10 10 10 100.06 0.06 0.06 0.06 0.06 0.06 0.06

380 465 380 465 380 465 380 465 470 585 530 665 530 665500 500 500 500 500 500 500343 343 343 343 343 343 34379 79 79 79 79 79 79368 453 368 453 368 453 368 453 458 573 518 653 518 653492 492 492 492 526 526 526458 458 458 458 458 458 45882 82 82 92 82 82 8282 98 85 106 90 113 91 115 137 165 152 188 175 211

Number of polesRATED CURRENT (A) [In] IEC, BS, VDE, ASNeutral pole ampere frame (A)RATED PRIMARY CURRENT OF OVERCURRENT TRIP DEVICES [ICT] (A)(For general feeder circuit use)

RATED CURRENT OF OVERCURRENT TRIP DEVICES [Io] (A)(For generator protection use)[Io] is the generator rated current

RATED IMPULSE WITHSTAND VOLTAGE [Uimp] (kV)AC RATED INSULATION VOLTAGE [Ui] (V)RATED OPERATIONAL VOLTAGE [Ue] (V)AC RATED BREAK. CAP. (kA r.m.s.)/MAKE CAP. (kA peak)

with Inst. 690V[Ics] =100% [Icu] 600V

500Vup to 415V

without Inst. 690V600V

up to 500VDC RATED BREAKING CAPACITY DC 250VDNV with Inst. 660V

600V480V

without Inst. up to 480VLR with Inst. 660V

without Inst. 600Vwith Inst. 480Vwithout Inst. up to 480V

AB with Inst. 660V600V480V

without Inst. up to 480VGL with Inst. 660V

600V480V

without Inst. up to 480VBV with Inst. 660V

600V500V

without Inst. up to 500VSHORT TIME WITHSTAND 1 secCURRENT [ICW] (kA) 3 secLatching current [kA]UTILIZATION CATEGORYOPERATION TIMESTotal breaking time (s)Spring charging time (s) max.Closing time (s) max.OUTLINE DIMENSIONS (mm)Fixed type a

bcd

Draw-out type abcd

Weight (kg) draw-out type

12

12

12

12

12

10

8

3

9

9

9

9

5

7 7 7

RATINGS UPTO 6300A ARE AVAILABLE ON REQUEST - FOR FURTHER DETAILS CONTACT MEM LTD. (500V)

19535 MEM ACB Catalogue ACs 3/3/01 4:43 pm Page 11 (1,1)

Memshield - ACB Ratings & Specifications MemshieldAir Circuit

Breakers

9

LIST NO: MACB06 MACB12 MACB16 MACB20 MACB25 MACB32 MACB40

DC Internal (mW) Draw-out type 0.050 0.040 0.034 0.028 0.020 0.015 0.011

resistance (per pole) Fixed type 0.040 0.025 0.021 0.015 0.013 0.010 0.007

Reactance (mW) Draw-out type 0.150 0.098 0.085 0.078 0.063 0.055 0.050

(per pole) Fixed type 0.150 0.098 0.085 0.078 0.063 0.055 0.050

AC Power(W) Draw-out type 110 280 380 540 690 900 1370

consumption Fixed Type 70 160 240 340 440 730 860

Note: The power consumption shown above is measured on the basis of internal AC resistance for 3 poles

Note: The values shown above are those measured on new parts and cannot be applied to components' terminals in the ACB.

Acc

esso

ries

Internal resistance, reactance, power consumption

De-rating

Dielectric withstand voltage

BASED AMBIENT TEMP LIST NO: MACB06 MACB12 MACB16 MACB20 MACB25 MACB32 MACB40STANDARDS (°C)

IEC947-2 40 (Standard ambient

630 1250 1600 2000 2500 3200 4000temperature)

BS EN 60947-2 45 630 1250 1600 2000 2500 3200 4000

VDE 0660 Part 101 50 630 1250 1600 2000 2380 3080 3890

55 630 1250 1600 1920 2300 2970 3740

AS 3858 1990 60 630 1230 1600 1840 2200 2850 3590

CIRCUIT 50/60 HZ

Main circuit Between terminals all terminals to earth AC3500V 1 minute

Auxiliary switch all terminals to earth AC2500V 1 minute

Undervoltage trip AC Rating terminals 9 - 10 to earth AC2500V 1 minute

terminals 11 - 12 to earth AC1500V 1 minute

DC Rating all terminals to earth AC1500V 1 minute

Shunt trip all terminals to earth AC2000V 1 minute

Overcurrent trip all terminals to earth AC2000V 1 minute

Motor charging closing AC100-250Vall terminals to earth

AC2000V 1 minute

control circuit DC100-220V

DC24-48V all terminals to earth AC500V 1 minute

Other Accessories all terminals to earth AC2000V 1 minute


Memshield - ACB Types of MountingMemshield Air CircuitBreakers

10

Terminal ArrangementBreaker Type Of Horizontal Vertical FrontList No Mounting Terminals Terminals Connections

Draw-outMACB06

Fixed –

Draw-outMACB12

Fixed –

Draw-outMACB16

Fixed –

Draw-outMACB20

Fixed –

Draw-outMACB25

Fixed –

Draw-outMACB32

Fixed –

Draw-out – –MACB40

Fixed – –

Note:- : Standard : Optional – : No or not available

Indication

TEST

Both main and control circuits are connected fornormal service.

Both main and control circuits are isolated. The switchboardpanel door can be shut. Earth circuit still connected.

Indication

ISOLATED

The ACB is completely removed from the cradle.

Indication

CONN.

The main circuit is isolated and the control circuits are connected. This position permits operation tests with the switchboard panel shut.

Control circuits

Main circuits

1 Connected position

4 Remove position

Vertical TerminalsHorizontal Terminals

This consists only of the circuit breaker with fixings to allow it to bemounted permanently inside the switchboard.

The draw-out type consists of a circuit breaker and a draw-outcradle. The circuit breaker can be removed from the cradle. There are four circuit breaker positions CONNECTED, TEST, ISOLATED and REMOVE. The switchboard panel door can be kept closed in CONNECTED, TEST and ISOLATED positions (“shut-in three positions”).

3 Isolated position

2 Test position

Draw-out type Fixed type

Main circuit terminals

Standard terminal arrangements are either horizontal or vertical type.(Horizontal and vertical types are available for MACB06, MACB12,MACB16 and MACB20). Front connections are also available.

Please refer to the table below and specify the required connectionmethod at time of ordering.


Memshield - ACB Accessories MemshieldAir Circuit

Breakers

11

The carrying rollers are necessarywhen the lifting truck is used. The rollers can also be used formoving the breaker on the floor.

The metal-clad type consists of a draw-out breaker, housed in asteel enclosure. A load centre isreadily constructed by simplyplacing metal-clad units one upon another.

Lifter List no D W H Weight (kg)

AWT-2B 1310 840 95 120

Dimensions (mm)

The loader is a variable size type to suit allframe sizes of Memshield ACBs (3 and 4 pole).

Size change is readily done by adjusting the loader.

Maximum safe working load (SWL) : 250kg

Maximum lifting height : 1850mm

Minimum passage width : 1800mm

Panel door

*150 max

ACB front panel

Breaker mounting position

Note: * If distance exceeds 150mm,contact MEM Ltd. (500V)

(Front view) (Plan view)

Panel doorBreakermountinghole

Dustplate

1513

0

20

0

Breaker

270

301.

512

.5ø10 ø7

250

50

20Panel door

A B(min.) (min.)

Hinge

A(min.)

Door interlock

AWT-2B

D

W

2300

mm

The door interlock prevents the switchboarddoor from being opened when the breaker isCLOSED. The door can be opened only whenthe breaker is OPEN. It is also fitted with alock release. Installation of the door interlockrequires simple drilling of the switchboardpanel door.

Hinge can only be fitted on the RIGHT HANDSIDE as shown in the opposite diagram.

Accessories are factory fitted and should be specified when ordering. An order form is shown on P48.

Door interlock

Lifting Truck

CARRYING ROLLERS

METAL-CLAD TYPE

The Arc Gas Barrier reduces the air gap requirement betweenthe top of the ACB and otherelectrical equipment or earthedmetal. See outline dimensiondrawings for details. The barrier can be installed with thecradle, for the draw-out typebreaker. The arc gas barrier is aheat proof, flame-resistantinsulating plate.

ARC GAS BARRIER

H

A B (3P) B (4P)MACB-06,12,16,20, 163 280 365MACB-25 208 330 445MACB-32,40 238 330 465


Memshield - ACB AccessoriesMemshield Air CircuitBreakers

12

Dustplate

Provides a dust proof seal between the ACB front panel and the cut-out on theswitchboard panel when the breaker islocated between the CONNECTED andISOLATED position.

Special environment specification

Cold Climate Treatment

Specify this treatment when the breaker isused in cold areas.

Specification: –40°C storage temperature

-25°C operating temperature (no condensation or freezing).

Anti-Corrosion Treatment

Anti-corrosion treatment permits the use of the breaker in a corrosive atmosphere. Contact MEM Ltd. (500V) for further information.

Tropicalization

(Fungus and Moisture Treatment)

Specify this treatment when the breaker isused under high temperature and highhumidity conditions:

Up to 60°C ambient temperature and up to 95% relative humidity (no condensation).

Earthing device

There is a growing demand in L.V. distribution for greater protection against electric shockparticularly during periods when maintenance work is being carried out on the main busbarsor cables. A safe and economical way to meet this requirement is to apply system earthing viathe normal service breaker. Earthing devices (optional) on Memshield ACBs comprises; Permanent parts which are factory fitted and are mounted on the ACB chassis and body toenable the ACB to receive the portable parts. Portable parts are supplied in loose kit form andare fitted on to the ACB body by the customer's engineer. This converts the ACB from anormal service device to an earthing device. For further information contact MEM Ltd. (500V) for details.

Door flange

Covers the panel cut-out on the switchboard.The panel cut-out should be greater than thestandard size shown in the outlinedimensions section of 250mm x 270mm. We would recommend to use a cut out of260mm x 280mm.

Permits the ACB to be padlockedin the OPEN position, this is fittedas standard.

Max. 3 padlocks (hasp size ø6 toø8mm) can be fitted (not supplied).

OPEN PADLOCK

Prevents unauthorised operationof the manual CLOSE and OPENbuttons. Padlock hasp size ø6 to ø8mm (not supplied).

PUSH-BUTTON PADLOCKCOVER

For use with hooks, ropes etcwhen lifting the breaker.

CARRYING HANDLE


60

Memshield - ACB Accessories MemshieldAir Circuit

Breakers

13

Key interlock

Breaker 1 Breaker 2

Bus-tieBreaker 3

Loads 1 Loads 2 Loads 1 Loads 2 Loads 1 Loads 2

SOURCE 1Breaker 1 Breaker 2

Bus-tieBreaker 3

SOURCE 1Breaker 1 Breaker 2

Bus-tieBreaker 3

Breaker 3 cannot be closed Breaker 2 cannot be closed Breaker 1 cannot be closed

IP cover Mechanical interlock

PC

NN

P P

*Min575mm

Rod

* Minimum pitch (575mm) ispossible if the proper insulatingdistance is obtained. For largerpitch (max. 1200mm) contact MEM Ltd.(500V) for details.

Select the required pitch from the table below:

Wire

Horizontal type Vertical type

Contact MEM Ltd.(500V) for the details ofvertical type with 3 ACBs.

N

N

The key interlock is a system of interlockingbetween breakers, each fitted with a lock-in-open type key lock

*The key must be inserted to release the lockbefore the breaker can be closed

* The breaker must be opened and locked in theopen position before the key can be removed

Utilising the lock-in-open type key lockfeature and using keys less than the numberof the key-locked breakers, an effective andreliable interlock system is formed.

Breakers can be supplied with a cylinder lockfitted or with a provision for Castell lock.

In the latter case, use Lock Type FS 2(angular movement 65

oclockwise to trap

key) Castell Locks Ltd.

EXAMPLE: Prevention of parallelconnection of two sources with a bus tie breaker.

Mounted on the switchboard panel door to provide IP54 degree of protection as defined in IEC529.

SOURCE 2 SOURCE 2SOURCE 2SOURCE 1

If you require to drawout the ACB with AOR-1B to the isolated position, anadditional depth frame is required with the IP54 cover. Please specify at the time of ordering.

600 700 800 900 1000

MACB06MACB12MACB16 • • •MACB20

MACB25MACB32 • • •MACB40

Interlock between

Pitch of ACB P(mm)(PC line to PC line)

PC P

C


Memshield - ACB AccessoriesMemshield Air CircuitBreakers

14

Auxiliary switch assembly Close-Open cycle counter

Auxiliary switches electrically indicate theopen-closed status of the breaker. For Draw-out Type, the auxiliary switches operate in the CONNECTED and TESTpositions only. However, where marineclassification society’s rules apply, theyoperate in the CONNECTED position only.Options include; 2A 2B, 5A 5B, 10A 10B.

Key lock

The key lock is available in two types: lock-in-open type to lock the breaker in theOPEN position, or lock-in-closed type to lockthe breaker in the CLOSED position.

Trip indication switch

Operation of the trip indication switch varies depending on which device trips the breaker and whether or not the closing springs are charged.

Auxiliary Switch RatingsRated Voltage Resistive Lamp **Inductive Motor

AC125-500V 7A 5A 7A 7ADC30V 7A 5A 7A 7ADC125V 7A 5A 5A 5ADC250V 7A 5A 2.5A 2.5A

Note: The minimum current limit is 10mA at 24V. DC** (AC cos ø over 0.4 DC L/R below 0.007)

This device counts and indicates the numberof close-open cycles.

Breaker tripped by

Undervoltage Remote openingtrip

Switch is ON for 40ms, then reset toOFF

Switch remains ON until closingsprings are charged

Switch remains ON until closing springsare charged after PUSH-TO-OPEN button is released

Switch remains ON until PUSH-TO-OPEN button is released

Operation of trip indication switch

Closing springs charged Closing springs discharged

Switch remains ON until closing springsare charged after undervoltage conditionhas restored to normal

Switch remains ON until undervoltagecondition is restored to normal.

Overcurrent trip (OCR)

Shunt trip

* Manual opening byPUSH-TO-OPEN button

UndervoltageCondition

Note: * Optional. The trip indication switch can be madeinoperative for a manual OFF operation. Please specify attime of ordering.

Automatic changeover controller

An automatic mains/generator changeoversystem can be achieved by utilizing thisdevice with a pair of mechanically interlockedACBs, each fitted with a motor operator,shunt trip and auxiliary switch.

If one or more phases fail on mains supply,the device will trip the mains circuit breakerand start the generator. Once up and running(85% of Ue) the generator circuit breaker willclose. If mains voltage should return thegenerator circuit breaker will trip, mains circuitbreaker will close and the generator willcontinue to run on 'No load' for a preset cooldown period.

Contact MEM Ltd. (500V) for further details.

Specifications

(Ue) System voltage level 110 ~ 440 V AC(Um) Mains fail voltage 75 ~ 95% Ue(Tf) Mains fail delay 0.5 ~ 8.0 sec.(Tr) Mains return delay 15 ~ 1200 sec.(Tg) Generator cool down time 30 ~ 1200 sec.

Dimensions

(W) 95 mm, (H) 143 mm, (D) 138 mm

Power supply

150mA @ 24V DC5% Maximum rippleAn optional UPS backup supply is availablefor this unit. It contains rechargeable batterieswhich can supply enough power to energise ashunt trip and keep the unit powered for upto 1 hour. Refer to page 45 for details.

RatingLoad Resistive Lamp Inductive MotorAC125-250V 7A 1.5A 6A 2ADC30V 6A 3A 6A 3ADC125V 0.6A 0.1A 0.6A 0.1ADC250V 0.3A 0.05A 0.3A 0.05A


Memshield - ACB Accessories for Draw-out Type MemshieldAir Circuit

Breakers

15

Main circuit safety shutters Position switches

When the breaker is drawn out the shuttersautomatically conceal and insulate the maincircuit disconnect contacts on the cradle.Each shutter can be padlocked in the closedposition. For safety during inspection andmaintenance, up to three padlocks may beapplied to each of the top and bottomshutters (padlocks not supplied).

The top shutter and bottom shutter can beopened or closed independently by manualoperation. Maintenance can be done in theopen position. (The mechanism is releasedautomatically by inserting the circuit breaker).The top shutter and bottom shutter can bothbe moved individually.

The Position switches operate when thebreaker is in CONNECTED position, TESTposition, ISOLATED position or in the INSERT position, to electrically indicate thebreaker position. These switches are dividedinto units (1) and (2) as shown below, and one switch can be selected from each unit. A max of 2 units can be fitted on ACBsMACB06~20, 3 Pole. A max of 4 units fittedon any other ACB size.

• Position switch, operating sequence

MAL-INSERTION PREVENTION DEVICE

a-contacts"ON"

a-contacts"ON"

(Connected)

a-contacts"ON"

a-contacts"ON"

Insert positionindicator switch

Isolated positionindicator switch

Test positionindicator switch

Connected positionindicator switch

Interchangeability exists within theMemshield range of Air Circuit Breakers.Because of this feature there is a possibilityfor a breaker of a different specificationbeing placed into the cradle. This iseffectively prevented by the use of the Mal-insertion Device.

TEST JUMPER

The test jumper allows open-close tests onthe removed breaker(The standard length of the cable is 5m)

BREAKER FIXING BLOCKS

These provide reinforcement for the breakermounting where vibration occurs. They arealways fitted when the breaker is subject tomarine classification society rules.

CONTROL CIRCUIT SAFETY SHUTTER

The control circuit disconnect contacts haveindependent shutters for increased safety.They are not padlockable.

(Isolated) (Test)

DRAW-OUT POSITION PADLOCK

The breaker can be padlocked in threepositions, CONNECTED, TEST and ISOLATED. The padlocking device is fitted as standard. Padlocks not supplied (hasp diameter 8 or 6mm).

UNITS (1) UNITS (2)

(1) CONNECTED (1) ISOLATED positionposition, indicator indicator switchesswitches (2 max) (2 max)

(2) TEST position, (2) INSERT position,indicator switches indicator switches(2 max) (2 max)

(3) CONNECTED (3) ISOLATED andand TEST position. INSERT position,indicator switches indicator switches(one each) (one each)

• Position switch ratings

Load Resistive Lamp Inductive Motor

AC250V 10A 1.5A 6A 2A

DC30V 6A 3A 6A 3A

DC125V 0.6A 0.1A 0.6A 0.1A

DC250V 0.3A 0.05A 0.3A 0.05A


Memshield ACB - Spring Charged OperationMemshield Air CircuitBreakers

16

Rating of motor charging type

Motor charging and closing operation

*CLOSING THE ACBCHARGING OF CLOSING SPRINGS *ANTI-PUMPING FUNCTION

When the closing springs are ‘DISCHARGED’, the spring charged OFFswitch in series with the motor is closed.

Control voltage is applied to terminals 1and 2 and the motor starts to charge the springs.

When the closing springs are fullycharged, the ‘spring charged OFFswitch’ in series with the motor opensand cuts the supply to the motor.

When the springs are charged, the‘spring charged ON switch’ in serieswith the LRC is closed.

Apply voltage across terminals 3 and 2,through PB (close). The latch releasecoil (LRC) is energized and the closingsprings are released to close the ACB.

Open the spring charged ON SW. byreleasing the closing spring and cuts the supply to the LRC by AUX SW. b-contact.

Once the closing springs have beenreleased, the ‘spring discharged OFFswitch’ is closed. If a close signal iscontinually applied across terminals 2 and 3, the holding relay (HC) is energized and self holds when the HC a-contact closes.

The HC b-contact opens, cutting thesupply to the LRC. ACB can not re-close without opening the PB (close).

* Refers to standard circuit

The closing springs are manually charged by pumping the charging handle. When thePUSH TO CLOSE button is pressed, theclosing springs are released, quickly closingthe breaker.

(An electrical latch release can be providedfor remote closing applications. The closingsprings must be charged manually prior toremote close operation).

The motor automatically charges the closingsprings. The latch release coil is energised bya remote push button, releasing the springsand quickly closing the circuit breaker. Withthe breaker closed, the motor automaticallystarts to charge the springs again for the nextclosing operation.

Manual charging is also possible.

Separate charging and closing circuits areavailable on request.

Manual charging type

Motor charging type

Breaker Rated voltage Min & max Inrush Steady-State Charging ClosingList No operation current current time command

voltage (peak value) (AC, A, currentr.m.s. value) (peak value)

(V) (V) (A) (A) (S) (A)

AC240 - 250 204 - 275 2.9 (240V) 0.5 2.8 1.6 (240V)AC200 - 230 170 - 253 3.4 (220V) 0.5 2.4 1.5 (220V)AC100 - 120 85 - 132 6.3 (110V) 1.2 2.4 3.1 (110V)DC200 - 220 150 - 242 2.8 (220V) 0.5 2.7 1.3 (220V)DC125 94 - 138 2.2 (125V) 0.8 3.0 3.4 (125V)DC100 - 110 75 - 121 6.5 (100V) 0.9 2.8 2.7 (100V)DC48 36 - 53 11.0 (48V) 1.7 3.0 4.9 (48V)DC24 18 - 26 16.9 (24V) 3.4 2.7 8.8 (24V)



MACB06MACB12MACB16MACB20

MACB25

MACB32MACB40

1

2

3

1

2

3

1

2


Memshield ACB - Spring Charged Operation MemshieldAir Circuit

Breakers

17

Motor circuit

Power transformer (external)

AUTOMATIC CLOSING SPRING RELEASE

Jigs can be supplied with the breaker forinspection and maintenance purposes (theyare required when changing the arcingcontacts of the ACB). Slow-closing operationcan be made by the charging handle whenthe slow-close jigs are installed.

SPRING CHARGED SWITCH JIG FOR SLOW-CLOSING

SourceforL.R.C.

Springchargedswitch

OFF

SpringchargedswitchOFF

AX

T-1B

A

AX

T-1C

AMT-1CA

XT-

1C

HC

M

LRC

Aux.S

w.

Sourceformotor

HC

A

C C

31

D D D

42

Springchargedswitch

ON

Interlock switch

PB (Close)

1 3

Split supply circuitStandard circuit

Source

2 4

204

203

205

41

31101

SpringchargedswitchOFF

AMT-1C

HC

Aux.S

w.

HC

C

3

D

4

PB (Close)

3

203

205

31101

D D

A

41

CSpringchargedswitch

OFF

Springchargedswitch

ON

AX

T-1C

AX

T-1C

2

2 4

M

1

1

Interlock switch

LRC

AX

T-1B

A

204

AX

T-1C

AX

T-1C

The maximum rated control power voltageapplicable to the motor charging type is 250V AC. If a higher voltage than this value is applied, a power transformer isrequired. MEM Ltd. (500V) can offer thefollowing transformers.

(please specify on order).

The closing springs are automaticallyreleased when the breaker is drawn out fromthe TEST position to the ISOLATED position.

This switch electrically indicates the chargedcondition of the closing springs.

R

R

15

Ry Ry etcFor spring chargeindication

B B

R

R

202202

B B

15

Ry Ry etcFor spring chargeindication

Transformer

AC350-395V TSE -30M 300VA 380 / 220VAC410-470V TSE -30M 300VA 450 / 220V

RatedControlVoltage Type Cap. Volt ratio

Ratings Resistive Motor

AC125V-250V 7A 4A

DC125V-250V 0.4A 0.05A


Memshield ACB - Electrical Tripping DevicesMemshield Air CircuitBreakers

18

Shunt trip (SHT)

The shunt trip device allows the ACB to beremotely opened. Instantaneous operatingand continuously rated versions are available.(Contact MEM Ltd. (500V) for details ofcontinuous rated type).

Memshield ACB can be fitted with shunt tripand UVT.

Control Circuit

Capacitor trip

Combined with the shunt trip device, thecapacitance trip device enables the ACB to be remotely tripped after a voltage (ac)drop due to a power failure, short circuit, etc, provided that the remote trip operationoccurs within 30 seconds after the voltage drop.

INP

UT

OU

TP

UT

CAPACITOR TRIP DEVICE

FRONT VIEW SIDE VIEW

CAPACITORCHARGE

RED NEONSWITCH

ON

173.0

161.0

151.0

OFF

4 - ø4.5 CSK mtg. holes

64.048

.0

80.0

51.0

28.0

4.0

12

43

NL

1

R

RC

7

AUXSW

SHT8

PowerSource

PB (OPEN)or OCR etc.

ACB

3 4 2

ON

PowerSwitch

OFF

DiDi Di

Outline Dimensions (mm)

+–

Shunt Trip Ratings (instantaneous operating type)

Shunt Trip Rated Voltage Operational Voltage Peak Excitation Opening TimeCurrent (max)

(V) (V) (A) (ms)

AVT-1 AC421-480 252-528 1.3 (450V) 30AC380-420 228-462 1.4 (380V) 30AC180-250 108-275 1.7 (220V) 30AC100-150 60-165 3.2 (110V) 30DC150-230 90-276 1.5 (220V) 30DC90 -125 54-150 2.9 (100V) 30DC48 29-57 4.9 (48V) 30DC24 14-28 8.9 (24V) 30

Type AQT-1A AQT-1BRated Voltage AC 100-120V 220~240VOperational Voltage 70 to 110% 70-110%Rated frequency 50/60Hz 50/60HzRated Voltage of Shunt Trip used DC90-125V DC150~230Power Consumption (Inrush) 100VA 200VA


Memshield Overcurrent Protection Relay (AOR1B)

Multi-function Protection Device

Memshield Air CircuitBreakers

20

Base current [Io]

For General Feeder Circuits1 Calculate the maximum full load current,

[ILOAD], through the ACB.

2 Select the required rated primary current,[ICT], of the OCR, (note that [ILOAD] mustnot be greater than [ICT].

3 Decide what the base current, [I0] shouldbe and use this as a reference for the LTD,STD, INST and PRE-TRIP current settings.

4 Select the OCR with the protection andindication functions required for theparticular application.

The base current, [I0], is used as the reference for deciding the current and timesettings of the LTD, STD, INST. and PRE-TRIP functions.

On AOR-1BL and AOR-1BM type OCRs, itcan be set by means of a dial on the front to50, 63, 80 or 100%, of the rated CT primarycurrent (ICT). On AOR-1BS, it is factory setaccording to the full load current of thegenerator (which should be specified at time of order).

Base current selection procedures are asfollows: (Refer to tables on P.24, 26, 28 foravailable values of [ICT] and [I0].

For Generator Protection1 Check the generator full load current,

[IGEN].2 The base current, [I0], will be equal to

[IGEN] and should be used as a referencefor the pick-up current settings of theother protection characteristics.

3 Select the OCR with the protection andindication functions required for theparticular application.

Note: The ground fault pick-up current,[IG] is a factor of [ICT], not [I0].

Protection functions

NON setting and FAIL-SAFE

2 If the STD and INST functions are bothset to 'NON' (thereby removing all short-circuit protection), the in-built FAIL-SAFE function will trip the ACB onfault currents exceeding 16 times thebase current [I0], instantaneously.

1 Each of the overcurrent protectionfunctions (LTD, STD, INST/MCR) can bedisabled by setting the respective pick updial to 'NON' position. (For example, theINST setting is often set to 'NON' toimprove selectivity levels.)

3 If the STD and MCR functions are bothset to 'NON', the in-built FAIL-SAFEfunction will trip the ACB on faultcurrents exceeding 10 times the basecurrent, [I0], (on L and M type OCRs) and5 times the base current, [I0] (on S typeOCRs). Trip time is the STD time setting.

1 Adjustable Long Time-delay LTD.The LTD function protects againstoverload. Select HOT or COLD start. The HOT start characteristic takesaccount of accumulated heating caused by previous loads.

(HOT start characteristics are notavailable on M type)

2 Adjustable Short Time-delay STDThe STD function is intended to give discrimination with other devices duringshort circuits. The STD characteristic isuser-selectable between 'definite time-delay' and 'I2t ramp' characteristics. The 'definite time-delay' is suitable for co-ordination with other definite timedelay devices. The 'ramp' characteristicallows closer co-ordination with thermal-magnetic MCCBs. When the STDis set to 'I2t ON', the 'ramp' characteristicis in operation up to 1000% of the basecurrent for L & M (general feederprotection) type OCRs and up to 500%for S (generator protection) type OCRs.Above these levels the definite time-delaycomes into operation. The STD is set to'I2t OFF' at the time of manufacture.

3 Adjustable Instantaneous Trip INST.The INST. function protects against shortcircuits, without a built-in time-delay, It isuser-selectable between 'INST.' or 'MCR'.The MCR (Making Current Release)function operates only during the closingcycle of the ACB and is disabled oncethe ACB has fully closed.

4 Adjustable Pre-Trip Alarm PRE-TRIPThe PRE-TRIP alarm gives warning (via a voltage free contact) of impendingtrip due to overload. On L and M typeOCRs, it has a definite time delay and onS type OCRs, it has an inverse time delay.

PRE-TRIP signal automatically resetswhen the current drops below pick-up current (IP).

5 Adjustable Ground Fault GFTThe GFT pick-up current can be setbetween 10% to 40% of the CT ratedprimary current and the definite timedelay between 80 to 1000ms.

6 Neutral Phase Protection N-phaseAvailable on 3 & 4 pole ACBs for use on 3-phase, 4 wire systems. The N-phase current setting is 20% to100% of the CT rated primary current.Please specify at time of ordering.

7 OCR Sealing FacilityUnauthorised access to the OCRadjustment dials can be prevented by use of an optional sealing cover. This isplaced over the dials and secured by two screws. The screw heads have holesdrilled in them for a sealing wire to befitted. (Wire and seal are not provided).

Pick-up current of LTD

Fluctuating current load profile

Microprocessor based relay with thermal memory.Simulates true heating effect of conductor.

Conventional electronic relay without thermal memory

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Documents

Memshield - ACB Ratings & Speciﬁcations Air Circuit Breakers · Memshield Memshield - ACB Ratings & Speciﬁcations Air Circuit ... BB B B B B B 0.05 0.05 0.05 0.05 ... A B (3P)