TM 1-1520-238-T-7
10–160.8
Change 8
10–48A.
FUEL QUANTITY SYSTEM – CAPACITANCE AND INDICATING TEST
10–48A
(USING PSD 60-1AF TEST SET) (cont)
Task
Result
c. Check capacitance of #2 AFT tank on test
set (fig. 10–70.5) LCD indicator.
d. Record capacitance of #2 AFT tank.
NOTE
If adjusted capacitance value is excessive, the helicopter fuel system
wire harness or connector pins may require replacement.
For older model aircraft the aft tank capacitance tolerance may be
increased to 1.5 pf.
e. Subtract #2 AFT T cable (fig. 10–70.7)
capacitance (step 2.r.) from #2 AFT tank
capacitance. Calculated capacitance value
should be 91.0 1.0 pf.
If calculated capacitance value is not within required
tolerance, go to paragraph 10–66.
Example:
91.4 pf
Actual indication on test set LCD indicator
- 0.3 pf
#2/AFT T cable capacitance
91.1 pf
Calculated value
f. Record #2 AFT empty tank calculated
capacitance value.
g. Detach T cable #2 AFT LOZ and #2 AFT
HIZ lead connectors from TANK UNITS
LOZ and TANK UNITS HIZ receptacle.
4. Perform fuel quantity system forward tank capacitance test as follows:
a. Attach T cable #1 FWD LOZ lead connector
to TANK UNITS LOZ receptacle.
b. Attach T cable #1 FWD HIZ lead connector
to TANK UNITS HIZ receptacle.
c. Check capacitance of #1 FWD tank on test
set LCD indicator.
d. Record #1 FWD tank capacitance value.
