TM 1-1520-238-T-4
4–91
4–14.
POWER PLANTS – WIRING INTERCONNECT DIAGRAM (cont)
4–14
NOTES:
HIGHWAY USE: THE ALPHA CHARACTER IDENTIFIES A SPECIFIC LINE, AND THE NUMBER IN PARENTHESIS IDENTIFIES THE SHEET
WHERE THE SIGNAL TERMINATES.
1. Np DEMAND:
PIN 18 - 20: 2.7 VDC.
PIN 19 - 20: 0.3 VDC.
PIN 20 - 21: 0 VDC AT ENGINE SPEED OF 20,900 RPM.
2. SIGNAL AT STARTER SPEED OF 15,000 - 16,000 RPM CAUSES TURBINE STARTER SWITCH A5
TO DEACTIVATE START CIRCUIT. (REMOVES 28 VDC OUTPUT FROM CLEAR RELAY - NOTE 3).
3. IN AUTO START SEQUENCE, TURBINE STARTER SWITCH A5 PROVIDES CLEAR RELAY 28 VDC OUTPUT
TO HOLD ENGINE START RELAY K1 - 5 / 6 OR K2 - 5 / 6 CLOSED AFTER START SWITCH S33 OR S34 IS RELEASED.
4. 28 VDC OUT WITH MASTER IGNITION SWITCH S121 ON AND ENG 1 OR 2 START SWITCH S33 OR S34 AT START POSITION.
5. 28 VDC OUT WITH MASTER IGNITION SWITCH S121 ON AND ENG 1 START SWITCH S33 AT IGNITION OVRD POSITION.
6. COLLAR IS SPRING LOADED TO CENTER (OFF) POSITION.
CHOP POSITION - COLLAR FORWARD AND ROTATED RIGHT.
RESET POSITION - COLLAR FORWARD AND ROTATED LEFT.
7. HAS DETENTS AT RUN AND CHOP POSITIONS; REMAINS AT LAST SELECTED DETENT POSITION.
8. 28 VDC INTO C1 OF ENG 1 OR ENG 2 IGNITION CUTOFF RELAY K1 - 7 / 8 OR K2 - 7 / 8 ENERGIZES RELAY, WHICH ENABLES
IT.
9. FROM ECU - ENERGIZES POWER CHECK LIGHT RELAY; APPLY 28 VDC TO MULTICHANNEL DIMMER CONTROLLER
FOR POWER CHECK INDICATOR.
10. ENG 1 IGNITION SYSTEM IS DISABLED BY SHORTING J1 - B10 TO J1 - B1 (THRU CONTACTS ON ENG 1 START RELAY
K1 - 5 / 6 AND ENG 2 IGNITION CUTOFF RELAY K1 - 7 / 8).
ENG 2 IGNITION SYSTEM IS DISABLED BY SHORTING J2 - B10 TO J2 - B2 (THRU CONTACTS ON ENG 2 START RELAY K2 - 5 / 6
AND ENG 2 IGNITION CUTOFF RELAY K2 - 7 / 8).
11. SWITCH TERMINALS CONNECTED AS FOLLOWS:
POSITION
TERMINALS CONNECTED
OFF
2 - 3, 5 - 6, 8 - 9, 11 - 12
BRAKE
2 - 3, 4 - 5, 7 - 8, 11 - 12
LOCK
1 - 2, 4 - 5, 7 - 8, 10 - 11
12. ELECTRICAL SYSTEM (TM 1-1520-238-T-6).
13. REFER TO PARAGRAPH 6-14. DRIVE SYSTEM - WIRING INTERCONNECT DIAGRAM.
14. UTILITY SYSTEM (TM 1-1520-238-T-8).
15. ENVIRONMENTAL CONTROL SYSTEM (TM 1-1520-238-T-8).
16. HYDRAULIC SYSTEM (TM 1-1520-238-T-5).
17. FUEL SYSTEM (TM 1-1520-238-T-7).
18. OPEN AT FLY (NORMAL FLIGHT) POSITION.
19. S9 AND S10 ARE GANGED SWITCHES AND OPERATE TOGETHER.
20. PREVENTS ENGINE 1 OR 2 POWER LEVERS FROM BEING ADVANCED PAST IDLE WITH ROTOR BRAKE ENGAGED.
21. ENGINE 2 POWER LEVER IDLE AND LOCKOUT STOPS WHEN ACTUATED BY CPG STOP RELEASE LEVER ON POWER LEVER.
22. ENGINE 1 POWER LEVER IDLE AND LOCKOUT STOPS WHEN ACTUATED BY CPG STOP RELEASE LEVER ON LOWER LEVER.
23. FROM ECU - PROVIDES
+15 VDC TO PILOT COLLECTIVE POTENTIOMETER POSITION TRANSDUCER.
24. SWITCH ACTIVATED BY ENGINE POWER LEVER POSITION.
N.D. - WITH POWER LEVER POSITIONED BETWEEN OFF AND IDLE.
N.C. - WITH POWER LEVER ADVANCED BEYOND IDLE.
25. HS DESIGNATES A HARD SPLICE WHICH CANNOT BE DISCONNECTED. M DESIGNATES A SOFT SPLICE
WHICH CAN BE DISCONNECTED FOR A WIRING CHECK.
26. HELICOPTERS WITH T700-GE-701C ENGINES INSTALLED ARE EQUIPPED WITH EMI SHIELDING.
27. HELICOPTERS WITH T700-GE-701C ENGINES INSTALLED ARE EQUIPPED WITH A DECU.
M58-018-21B
SHEET 21 OF 21
