Post on 17-Jan-2016
Installation and Testing Installation and Testing of Optical of Optical
HarnessesHarnesses
John Matheson Rutherford Appleton Laboratory
Schedule for test and assembly
Outline of required tests
Acceptance testing
Assembly to discs
Final testing
Schedule for Test and Schedule for Test and Assembly: BarrelAssembly: Barrel
• B3: 64 harnessesB3: 64 harnesses
• B4: 80 harnessesB4: 80 harnesses
• B5: 96 harnessesB5: 96 harnesses
• B6: 112 harnessesB6: 112 harnesses
B3: 50 days April 02 -> June 02
B4,B5,B6: Oct 02 -> Mar 03
delivery -> installation ~35 days• 1 man hour for acceptance test
• 2hr for assy to barrel / final test
Schedule for Test and Schedule for Test and Assembly: ForwardAssembly: Forward
• D1,D7,D8: 16 D1,D7,D8: 16 harnesses/discharnesses/disc
• D2,D3,D4,D5,D6: 24 D2,D3,D4,D5,D6: 24 harnesses/discharnesses/disc
• D9: 12 harnesses/discD9: 12 harnesses/disc
• Total 360 (2 end caps)Total 360 (2 end caps)
• services to discs 7/10/02 on (90 days) => 10hr/harness
• 3 full-time technical staff foreseen for assembly/testing of services for barrels and discs
Barrel HarnessBarrel Harness
• DORIC and VDC
• opto package
• power tapes, redundancy system
• many traces and connections
Forward HarnessForward Harness
• forward harness consists of opto packages and optical fibres only
• latest version - no plastic cover
• test LI, responsivity in DC conditions
Test Fixture for Forward Test Fixture for Forward Plug-insPlug-ins
• equivalent to forward module
• design will be transferred to 6 PCBs
• allows testing of BER
What measurements do What measurements do we need ?we need ?
• VCSEL LI curves
• pin diode responsivity
• radiation hardness (batch acceptance)
• BER scan/BER long term
• thermal cycling/burn-in (during manufacture)
• power tape continuity ?
• power tape insulation ?
BER testing: TTC linkBER testing: TTC link
SLOG
LITMUS
OPTIF
TTC link results: BER scanTTC link results: BER scan
TTC BER Scan
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0 100 200 300
OptIF DAC Value
BE
R
dog-leg1
dog-leg2
dog-leg3
dog-leg4
dog-leg5
dog-leg6
• vary light power into p-i-n diode
• allows definition of working range
• BER scans < 5 min
VCSEL LI CurvesVCSEL LI Curves
SCTLV
SLOG
SCTLV
• scan I using SCTLV
• measure photocurrent in LAPD
• 50% duty cycle
• 5 min. setup/run time
LAPD
DMM
PIN ResponsivityPIN Responsivity
SCTLV
SCTLV
LED
DMM supply
LAPD
• measure I in pin bias line
• LEDs for reproducibility
• LAPD used to calibrate LEDs
• 10 min. setup/run
Acceptance testing at Acceptance testing at RALRAL
Both harnesses:
• responsivity 10 min
• VCSEL L-I curve 5 min
• BER scans data and TTC 30 min
Barrel harness additional:
• HV insulation resistance 5 min
• continuity/shorts 5 min
• redundancy system 10 min
Total time: barrel = 1 hr, forward = 45 min
Forward harness Forward harness installation: installation: assembly formerassembly former
• services assembled to former
• former used to populate quadrant
• after 4 quadrants, align cooling blocks
Forward harness Forward harness installation: procedureinstallation: procedure
• cooling pipes soldered on jig
• mount services on front former
1. dummy modules
2. cooling pipes
3. power tapes
4. opto-harnesses• transfer services to disc
• fix cooling blocks temporarily
• connect patch panels
test each quadrant whilst re-populating the former because:1. quicker
2. next step, align and glue blocks
• turn disc over and repeat
Final testing during Final testing during installationinstallation
Both harnesses:
• responsivity 0 min
• VCSEL L-I curve 0 min
• BER scans data and TTC 30 min
• BER long-term 60 min
Barrel harness additional:
• HV insulation resistance 0 min
• continuity/shorts 5 min
• redundancy system 10 min
Total time:
barrel = 1 hr 45 min, forward = 90 min
• procedures for installation and testing are well defined
• expect 3 technicians for harnesses
• 1 man-hour/harness, acceptance
• 2 hours / harness, test + installationSchedule is achievable but requires care in execution
• first barrel will arrive April 02, timescale less critical
• will allow refinement of procedures