TM 1-1520-238-T-7
10–221
10–77. PRESSURE REFUELING/DEFUELING – WIRING INTERCONNECT DIAGRAM (cont)
10–77
NOTES:
1.
CONTROLS FUEL TRANSFER SHUTOFF VALVE L17.
2.
MUST BE CLOSED FOR FUEL TRANSFER (INTERNAL SWITCH
SHOWN AT VALVE CLOSED POSITION).
3.
CLOSES FLOAT BOWL OUTLET WITH 28 VDC IN TO ALLOW FLOAT
AND POPPET TO INCREASE PRESSURE IN PILOT VALVE HOSE.
WHEN TANK IS FULL OR WHEN TANK LVL CONT VALVE SWITCH
IS AT CLOSE, THE INCREASED PRESSURE CLOSES ASSOCIATED
FUEL/DEFUEL VALVE.
4.
TANK FILLS THROUGH THIS VALVE WHICH OPENS INTERNAL VALVE
SWITCH WHEN FUEL FLOWS. (FUEL/DEFUEL VALVE CONTROLS
ISOLATION FUEL VALVE SWITCH.)
5.
DS1 AND REFUEL VALVE OPEN INDICATOR LIGHTS WHEN RELAY
K3-4 ENERGIZES AT OPEN POSITION OF VALVE L17.
6.
LIGHTS AT CLOSING OF AFT FUEL/DEFUEL VALVE BY CLOSING
S3 ONLY; WILL NOT LIGHT IF AFT TANK LVL CONT VALVE SWITCH IS
IN OPEN POSITION.
7.
LIGHTS AT CLOSING OF FWD FUEL/DEFUEL VALVE BY CLOSING
S2 ONLY; WILL NOT LIGHT IF FWD TANK LVL CONT VALVE SWITCH IS
IN
OPEN POSITION.
8.
WITH S4 ON, DS1, DS2 AND DS3 LIGHT WHEN PRESSED, THROUGH
CONTACT 3 (PRESS TO TEST).
9.
GROUND SIGNAL MUST BE PROVIDED THROUGH CONTACT 2
(FROM FUEL/DEFUEL VALVE SWITCH) BEFORE SWITCH CONTROL
SOLENOID GROUND CAN BE PROVIDED THROUGH CONTACT 1.
10. INSTRUMENTS (TM 1-1520-238-T-5).
11. ELECTRICAL SYSTEM (TM 1-1520-238-T-6).
12. HS DESIGNATES A HARD SPLICE WHICH CANNOT BE DISCONNECTED.
13. AUXILIARY POWER UNIT (TM 1-1520-238-T-8).
14. REFER TO PARAGRAPH 10-49. FUEL QUANTITY INDICATION/
TRANSFER - WIRING INTERCONNECT DIAGRAM.
M70-004-6
SHEET 6 OF 6
HIGHWAY USE: THE ALPHA CHARACTER IDENTIFIES A SPECIFIC LINE, AND THE NUMBER IN
PARENTHESIS IDENTIFIES THE SHEET NUMBER WHERE THE SIGNAL TERMINATES.
