HWC with nQPS Splice MonitoringZinur Charifoulline & Bob Flora 07.04.2009

HWC with nQPS Splice MonitoringZinur Charifoulline & Bob Flora 07.04.2009

• Real Time (~10 sec) BUS Voltage Energy Extraction Trip

• 300 µV threshold on Un-bypassed BUS

• Splice (Resistance) Monitor (>1 hour) Continuous Advice

• Un-bypassed BUS Splices (Hi-Res < nΩ) able to measure even good splices

• Provide Calibration Data for Real Time Bus Inductance Cancelation

• Bypassed MAGNET Splices (Low-Res ?) able to detect bad splice

• Legacy Snapshot MAGNET Splice (Resistance) Display

• Old slightly invasive technique used only during special measurement campaigns

• Warm BUS Resistance Tunnel Measurements (ELQA)

• Must be completed prior to cool down

• Real Time (~10 sec) BUS Voltage Energy Extraction Trip

• 300 µV threshold on Un-bypassed BUS

• Splice (Resistance) Monitor (>1 hour) Continuous Advice

• Un-bypassed BUS Splices (Hi-Res < nΩ) able to measure even good splices

• Provide Calibration Data for Real Time Bus Inductance Cancelation

• Bypassed MAGNET Splices (Low-Res ?) able to detect bad splice

• Legacy Snapshot MAGNET Splice (Resistance) Display

• Old slightly invasive technique used only during special measurement campaigns

• Warm BUS Resistance Tunnel Measurements (ELQA)

• Must be completed prior to cool down

PurposePurpose: To continuously monitor, display, and track all splice : To continuously monitor, display, and track all splice resistances in the LHC main 13 kA circuits.resistances in the LHC main 13 kA circuits.

(PVSS should display live bus segment voltages in a manor similar to what is now done for the quench signals.)

SMSM

FunctionFunction: Fully automated data acquisition, analysis, and visual displays.: Fully automated data acquisition, analysis, and visual displays.

Main Circuit Main Circuit SSpliceplice Resistance Resistance MMonitoronitor

• Space

• Summary View

• Sector -> Circuit -> Element(Bus/Mag)

• Mean, Standard Deviation, Extrema

• Alarms and Limits

• Sector Views (8)

• Circuit -> Element(Bus/Mag) -> Arc Position

• Distribution (along Arc and Density)

• Alarms and Limits

• Time

• Automatic

• One hour before Powering to Now

• (until One hour after Powering)

• Elective

• Any time Window

• Change from Past Powering (Now- Past)

• Time Evolution: 3D water fall plot

• Space

• Summary View

• Sector -> Circuit -> Element(Bus/Mag)

• Mean, Standard Deviation, Extrema

• Alarms and Limits

• Sector Views (8)

• Circuit -> Element(Bus/Mag) -> Arc Position

• Distribution (along Arc and Density)

• Alarms and Limits

• Time

• Automatic

• One hour before Powering to Now

• (until One hour after Powering)

• Elective

• Any time Window

• Change from Past Powering (Now- Past)

• Time Evolution: 3D water fall plot

Splice Monitor Scope

Splice Monitor Data• Reference Parameters

• # of Splices / Segment

• Segment Names (Int /Ext)

• Current & Voltage Signals

• Only One Point every 10 seconds

• Fully Resolved Floating Point

• No Dead Band

• No Missing Bits

• Event Detection

• Auto Poll Current

• Analysis

• Auto Plateau Extraction

• All Point LLSFIT (Fall Back)

• dI/dt term, useful for calibration

• Normalization

• ∑R (none)

• ∑R/N (average)

• ∑R-(N-1)<R> (preferred)

• Resistance Archive Storage for History Tracking

RB.A67, 14/11/2008, 15h35, I=2000A(up)

B32R6: R=48±88nΩ, R2=0.980

BAD?BAD?

BAD?

BAD?

4 hours

RB.A67, 14/11/2008, 15h40, I=3000A(up)

B32R6: R=46±15nΩ, R2=0.989

BAD? BAD?

4 hours

RB.A67, 14/11/2008, 15h50, I=4000A(up)

B32R6: R=46±6nΩ, R2=0.995

BAD?BAD?

4 hours

RB.A67, 14/11/2008, 16h00, I=5000A(up)

B32R6: R=46±4nΩ, R2=0.997

BAD!BAD?

4 hours

RB.A67, 14/11/2008, 16h20, I=5000A(up)

B32R6: R=47±3nΩ, R2=0.997

BAD!

BAD?

4 hours

RB.A67, 14/11/2008, 17h05, I=5000A(up)

B32R6: R=47±3nΩ, R2=0.997

BAD!

BAD?

4 hours

RB.A67, 14/11/2008, 17h15, I=6000A(up)

B32R6: R=49±4nΩ, R2=0.991

BAD!

BAD?

4 hours

RB.A67, 14/11/2008, 17h20, I=7000A(up)

B32R6: R=49±3nΩ, R2=0.993

BAD!

BAD?

4 hours

RB.A67, 14/11/2008, 17h50, I=7000A(up)

B32R6: R=48±3nΩ, R2=0.993

BAD!

OK?

4 hours

RB.A67, 14/11/2008, 18h05, I=7000A(up)

B32R6: R=49±3nΩ, R2=0.993

BAD!

4 hours

RB.A67, 14/11/2008, 18h20, I=7000A(up)

B32R6: R=49±3nΩ, R2=0.993

BAD!

4 hours

RB.A67, 14/11/2008, 18h30, I=6000A(down)

B32R6: R=49±3nΩ, R2=0.993

BAD!

4 hours

RB.A67, 14/11/2008, 18h40, I=5000A(down)

B32R6: R=49±4nΩ, R2=0.986

BAD!

4 hours

RB.A67, 14/11/2008, 18h45, I=4000A(down)

B32R6: R=49±3nΩ, R2=0.985

BAD!

4 hours

RB.A67, 14/11/2008, 18h50, I=3000A(down)

B32R6: R=48±3nΩ, R2=0.985

BAD!

4 hours

RB.A67, 14/11/2008, 19h00, I=2000A(down)

B32R6: R=49±3nΩ, R2=0.985

BAD!

4 hours

RB.A67, 14/11/2008, 19h10, I=1000A(down)

B32R6: R=49±3nΩ, R2=0.986

BAD!

4 hours

RB.A67, 14/11/2008, 19h30, I=0A(down)

B32R6: R=49±3nΩ, R2=0.988

BAD!

4 hours

23

The nQPS Splice Monitor will feature Histogram dirtributions of the splice

resistances over the full arc.This will allow us to distinguish between “normal

variations” and a significantly compromised splice.

Legacy Legacy SSnapshotnapshot SD SD Magnet Splice Magnet Splice DDisplayisplay

Driven by the Sequencer for each Main Circuit Invoked by the Sequencer

Starting at zero current & after ramping to each new plateau

Snapshot Pairs Provoked by the Sequencer

Board B

Board A

Each New Snapshot Pair Data Set Delivered to the SD by Sequencer

Current (I) & All Snapshot Data for Each Magnet from both A & B

SD Display Updated for Each New Snapshot Pair Data Set

Driven by the Sequencer for each Main Circuit Invoked by the Sequencer

Starting at zero current & after ramping to each new plateau

Snapshot Pairs Provoked by the Sequencer

Board B

Board A

Each New Snapshot Pair Data Set Delivered to the SD by Sequencer

Current (I) & All Snapshot Data for Each Magnet from both A & B

SD Display Updated for Each New Snapshot Pair Data Set

Legacy Legacy SSnapshot SDnapshot SDMagnet Splice Magnet Splice DDisplayisplay

Summary View Based on Best Archived Measurements to Date

Sector -> Circuit -> (Body / Center)

(A + B)/2 = Magnet Body Splices (Center) ± identifies which half

(A - B)/2 = Center Splice

Possibility to Show A and B separately

Extrema, Mean and Standard Deviation

Sector View Circuit -> (Body / Center) -> Arc Position

Distribution (along Arc and Density)

Alarms and Limits

Summary View Based on Best Archived Measurements to Date

Sector -> Circuit -> (Body / Center)

(A + B)/2 = Magnet Body Splices (Center) ± identifies which half

(A - B)/2 = Center Splice

Possibility to Show A and B separately

Extrema, Mean and Standard Deviation

Sector View Circuit -> (Body / Center) -> Arc Position

Distribution (along Arc and Density)

Alarms and Limits

A. Verweij, TE-MPE. 24 Feb 2009, QPS Review

Good joint of about < 2 nΩ

Bad electrical contact between wedge and U-profile with the bus on at least 1 side of the joint Bad contact at joint with the U-

profile and the wedge

=13 kA, 13 kA, external triggerexternal trigger

An electrical fuse is a current interrupting device which protects an electrical circuit in which it is installed by creating an open circuit condition in response to excessive current. The current is interrupted when the element which carries the current is melted by heat generated by the current. Most types of fuses are designed to minimize damage to conductors and insulation from excessive current.

Thanks to:

• Warm Warm BUSBUS Resistance Tunnel Resistance Tunnel MeasurementsMeasurements

• Warm BUS Resistance Tunnel Measurements

• Warm BUS Resistance Tunnel Measurements

• Measurement must be done on a Warm sector

• Currently Sectors: 12 34 56 67

• A 2 cm Stabilizer Defect will increase the Resistance by 1%

• But so will a 1% variation in Temperature (currently 1-3%)

• Compensate for Temperature and possibly length Variations

• Measure the Resistance of each Bus segment

• Manually with Biddle (Microhmeter) to explore Feasibility and Sensitivity

• or with DVM in Tunnel

• Small bench top 250 V supply

• Drive 3 A through the Bus and Diodes

• With new Automated QPS system in the Future