Installation and Testing of Optical Harnesses 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 Assembly: 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 Assembly: Forward D1,D7,D8: 16 harnesses/discD1,D7,D8: 16 harnesses/disc D2,D3,D4,D5,D6: 24 harnesses/discD2,D3,D4,D5,D6: 24 harnesses/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 Harness DORIC and VDC opto package power tapes, redundancy system many traces and connections
Forward 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 Plug-ins equivalent to forward module design will be transferred to 6 PCBs allows testing of BER
What measurements do 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 link SLOG SLOG LITMUSLITMUS OPTIFOPTIF
TTC link results: BER scan vary light power into p-i-n diode allows definition of working range BER scans < 5 min
VCSEL LI Curves SCTLVSCTLV SLOGSLOG SCTLVSCTLV scan I using SCTLV measure photocurrent in LAPD 50% duty cycle 5 min. setup/run time LAPD DMM
PIN Responsivity SCTLVSCTLV SCTLVSCTLV LEDLED DMMsupply LAPD measure I in pin bias line LEDs for reproducibility LAPD used to calibrate LEDs 10 min. setup/run
Acceptance testing at RAL 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 installation: assembly former services assembled to former former used to populate quadrant after 4 quadrants, align cooling blocks
Forward harness installation: 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 installation 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 + installation Schedule is achievable but requires care in execution first barrel will arrive April 02, timescale less critical will allow refinement of procedures