LAT  Electronics, Data Acquisition & Instrument Flight Software

  Subsystem Manager:  Gunther Haller

 

Important: EM2 test-stand hardware components are NOT compatible with hardware supplied for EM1 test-stands. Do not mix TEM/TEM-PS/Transition Card EM1 with EM2 hardware. Hardware for EM2 is marked "EM2" on the TEM, TEM-PS, VME Transition Card and LCB supplied.

Documents:

The documents are in the process of being transferred to the LAT-DOC system for official release, please retrieve them from LATDOC's.

Here are applicable document numbers and selected copies of the documents in the release cycle (use them with caution).

Note that we do not perform impedance/short/open/voltage measurements on all pins, but test functionality of the system. The "safe-to-mate" test is the responsibility of the sub-system.

Calorimeter:

EGSE-CAL-FM TESTSTAND #1

LAT Quality Assurance

Performance & Safety Assurance LAT NCR Report

The following Nonconformance Report # 00195 was submitted on 09/30/04 14:03:07

 

Entered by Ludvik, Jeffrey - jsludvik@slac.stanford.edu

 

Found by:  Customer Complaint

Type of Nonconformance:  Minor

Discrepancy Level:  Non-Flight Hardware

Sub-System:  Electronics (ELEC)

Item Description:  EGSE CAL FM01 EM2 TPS

Supplier: 

Location: 

Drawing/Rev #:   

Lot/Heat #: 

Serial #:  GLAT0650

Test Procedure/Rev #: 

 
Description of Nonconformance:  NRL returned only the TPS from CAL FM01 teststand. NRL reported the TPS as failed during vibration testing and failed to power on, "Power on 28V current ~20mA". The TPS was tested immediately by SLAC and the TPS failed to power on, as reported by NRL. Upon further analysis, an inductor on the TPS was determined to have been damaged. The TPS was staked at SLAC, not an outside vendor, and had gaps underneath all of the inductors, possibly identifying the reason for the failure.
       

Disposition Area

Defect Code:  090 Mechanical

Disposition:  Rework 
(Valid  dispositions:  Rework, Repair, Use-as-is, Reclassify, Return to Vendor, Scrap, or Documentation Change)

Disposition Instructions:  The non-flight inductor L1 on the TPS was found to have a broken lead. This was due to incomplete staking of the inductor. The staking was done in house at SLAC and not at an outside vendor per drawing. A large gap of no staking compound was clearly visible under the inductor. The inductor was replaced, and the TPS passed all performance electrical testing. This TPS will only be used for internal use only with no additional vibration. A replacement TPS, prepped for vibration, will be sent to the NRL.

NCR closure approved by Y.C. Liew, LAT Quality Engineering, and David Nelson, LAT DAQ Engineering (e-mails on file).

Root Cause:  Incomplete staking of inductor.

Action taken to Preclude Recurrence of Discrepancy:  All TPS are staked and conformal coated at an outside vendor and done to specification according to the drawing.