Torque Indicating (Ti) Calibration Test − Maintenance Practices - De Havilland DASH8 100 Series Maintenance Manual

**ON A/C ALL
TORQUE INDICATING (TI) CALIBRATION TEST − MAINTENANCE PRACTICES
1. Adjustment/Test
Equipment and Materials:
Digital Voltmeter 0 to 10 + or − 0.001 Volts
Power Supply 0 to 10 Volts (variable)
Test Cable (locally manufactured)
A. Torque Indicating (TRQ) Calibration Test
(1) With dc power on, press test pushbutton on indicator. Check pointer at 105%
opposite blue dot and digital readout at 105. Check on release of pushbutton,
indicator returns to original setting.
(2) Open circuit breaker ENG 1 TORQUE IND (K6) on 28V dc left essential bus circuit
breaker panel (engine No. 1) or ENG 2 TORQUE IND (J5) on 28V dc right essential
bus circuit breaker panel (engine No. 2). Ensure pointer moves off−scale and digital
readout blanks. Close circuit breaker.
(3) Open and clip following circuit breakers:
(a) Power to signal conditioning unit (SCU).
ENG 1 TORQUE COND (L6) ON 28V dc left essential bus circuit breaker
panel. (When checking engine No. 1 torque indicating system).
OR
ENG 2 TORQUE COND (K5) on 28V dc right essential bus circuit breaker
panel. (When checking engine No. 2 torque indicating system.
(b) Power to engine electronic control unit (ECU).
ECU ENG 1 (K4) on 28V dc left essential bus circuit breaker panel and
ECU ENG 1 (J7) (Mod 8/0488) on right 28V dc essential bus circuit breaker
panel. (When checking engine No. 1 torque indicating system).
OR
ECU ENG 2 (H3) on 28V dc right essential bus circuit breaker panel and
ECU ENG 2 (M8) (Mod 8/0488) on 28V dc left essential bus circuit breaker
panel. (When checking engine No. 2 torque indicating system).
(c) Power to Flight Data Recorder (FDR).
FDAU (G2) and FDR STAT (H2) on 28V dc left essential bus circuit
breaker panel and FDR (A9) on Avionics circuit breaker panel. If engine
cowls fitted, gain access to SCU and ECU by opening and staying left side
cowl of appropriate engine.
(4) Disconnect electrical connectors 7700−P1 at ECU, 7700−P7 at SCU and at station
X210 on left side of cabin (behind avionics rack) disconnect electrical connector
9811−P104 on relay panel (refer to Figure 201).
(5) Carry out resistance, continuity and insulation check of pick up probe (refer to
Engine Maintenance Manual).
(6) Connect variable voltage power across pins 3 (HI+) and 4 (LO−) and 5V (reference
voltage) to pin 5 of connector 7700−P7).
MASTER
EFFECTIVITY: See Pageblock 77−10−11 page 201
D
S ERIES 100
AIRCRAFT MAINTENANCE MANUAL
77−10−11
Dec 20/2004
Page 201