T M 5 5 - 4 9 2 0 - 4 2 8 - 1
f. (See fig. 2-3.) PUSH and hold the LOW PRESS RELIEF VALVE and HIGH PRESS RELIEF
VALVE. Release the relief valves after 15 seconds.
g. Set the RETURN, SAS PRESS, and ILCA PRESS valves to OFF.
h. Press the hydraulic unit SOLENOID valve to CLOSED. Pressure indications on the LOW and
HIGH PRESS gages shall drop to 0 and the SOLENOID valve light shall go out.
i. (See fig. 2-2.) Set the electrical unit SOLENOID SHUTOFF switch to CLOSED. The switch
OPEN light shall go out and the CLOSED light shall come on.
j. Set the electrical unit power switch to OFF. The LAMP TEST switch POWER light shall go out.
The test set is ready for use. If ILCA or extensible link tests are to be
performed, refer to the test procedures in TM 55-1520-240-23.
2-11. Emergency Shutdown Procedures.
When there is not sufficient time to perform a normal shutdown, perform an emergency shutdown as
a. Shut down hydraulic pressure by performing the task that is most expedient:
(1) (See fig. 2-3.) Push the SOLENOID valve knob on the hydraulic unit to CLOSED.
(2) (See fig. 2-2.) Push the SOLENOID SHUTOFF switch on the electrical unit to CLOSED.
(3) Set the electrical unit power switch to OFF.
(4) (See fig. 2-6.) Close the shop hydraulic SUPPLY needle valve.
6. Following an emergency shutdown, secure the test set as follows:
(1) (See fig. 2-3.) Set the ILCA PRESS and SAS PRESS selector valves to VENT and then to OFF.
(2) Set the RETURN selector valves to RETURN and then to OFF.
(3) PUSH and hold the HIGH PRESS and LOW PRESS RELIEF VALVES. Release the valves
after 15 seconds.
(4) Set the HIGH PRESS SHUTOFF VALVE to CLOSED
(5) Set the HIGH PRESS REGULATOR to DECREASE.
c. Correct reason for emergency shutdown prior to reapplying power.
2-12. Disconnect and Securing Procedures.
Proceed as follows:
u. (See fig. 2-.3.) Check that the electrical unit power switch is at OFF.
b. Disconnect the CYCLE MOTOR and SOLENOID cable, the power cable, and the NO. 1 and NO.
2 system electrical cables from the hydraulic and electrical unit receptacles. Stow the cables in the cover
of the electrical unit. (See fig. 1-2.)
c. Disconnect the SUPPLY and RETURN hoses from the hydraulic power supply and the hydraulic
unit. Drain fluid and plug the ends of each hose. Plug the SUPPLY and RETURN ports.
d. (See fig. 1-3.) Secure the CASE VENT LINE hose to the hydraulic unit panel.
e. Secure the 5-in. dial indicator, contact point to the left, to the ILCA manifold, using the thumb
f. Stow the bearing using PIN 3. Stow PIN 1 and PIN 2.
2 - 2