barfield DC400, User Instruction

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61-101-00802.EF2 (REV. G) CH. 2
January 7, 2015 Page 26 of 44
6. PREFERRED CALIBRATION TEST (WITH DRY TANKS)
Note: See PRECAUTIONS and PRELIMINARY sections (Chapter 1).
Note: When draining facilities are not readily available, the Alternate Calibration
Test (Chapter 3, Section 2) may be used as a temporary measure.
The preferred calibration is done with dry tanks. This method is the most
accurate for calibration since the indicator zero reading is set to the actual empty
tank condition. A capacitance value, applied to system by the test set, is
substituted for an equivalent quantity of fuel in the tanks. The indicator is
adjusted to read the substituted fuel quantity.
A. Aircraft Preparation
CAUTION: Refer to the Aircraft Maintenance Manual for proper
defueling and fueling procedures. Observe all safety
precautions.
(1) Ensure aircraft is defueled. Drain sumps.
(2) Disconnect the aircraft battery.
(3) Maintain the circuit breakers open.
(4) Access the indicator.
(5) Disconnect the aircraft wiring plug from the indicator.
B. Test Set Preparation
(1) Insure the test set ON/OFF switch is OFF.
(2) Rotate theTEST FUNCTION switch to CAP SIM CAL (NORM SYS).
(3) Set the INSULATION/SYSTEM switch to SYSTEM.
(4) Set the MAIN/TOT-AUX/NAC switch to MAIN/TOT.
(5) Set the 200 (pF)/1000 (pF) switch to 200 (pF).
(6) Set the CAP SIM (pF) 100’s thumbwheels to “1“. Set the 10’s to "0"
for the UA & UB serial numbers and "3" for the UC and UE serial
numbers.
C. Connecting Test Set
(1) Determine number of pins on indicator connector and connect test set
as shown in Figure 9 or Figure 10 accordingly.