TM 55-2840-251-23
7-5 THERMOCOUPLE HARNESS (AVIM) (Continued)
7-5-2 INSPECTION
1.
Inspect harness for:
- Frayed or broken braiding
- Loose terminal post
- Broken terminal lugs
2.
Replace harness if:
- Braiding frayed or broken
3.
Repair harness (Task 7-5-4) if:
- Terminal post loose
- Terminal lugs broken
7-5-3 TESTING
Busbar Type
1.
Check insulation resistance is not less than 10
megohms at 100 volts AC or DC after drying for 1 hour
at 500°F.
2.
Check that resistance between alumel to alumel
terminals is 0.178 to 0.218 ohms.
3.
Check that resistance between chromel to chromel
terminals is 0.389 to 0.475 ohms.
4.
Connect center zero meter negative lead to alumel
post, positive lead to chromel post on terminal block.
5.
Heat thermocouple probes with soldering iron and
check that meter shows positive (+) deflection for each
probe.
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