TM 9-4120-385-14
NOTE
The nitrogen cylinder gauge should be calibrated from 0 to
1000 psig.
the high pressure switch. Continuity should be indicated on the multimeter.
(e) Slowly increase the nitrogen pressure. The switch should trip at 480 psig
+/ 10 psig. The switch tripping will be indicated by a break in continuity. Replace switch if it
does not operate within tolerances.
(f) Reduce the nitrogen pressure to zero and disconnect the nitrogen cylinder and
multimeter from the high pressure switch.
5. Low Pressure Switch Testing.
(a) Tag and disconnect low pressure switch electrical leads. Connect a
(b) Connect a nitrogen cylinder to the low pressure switch sensing line.
should be indicated.
(d) Slowly decrease the nitrogen pressure. The switch should tip at 25 psig +/
5 psig. Continuity will be broken when the switch trips. Replace switch if it does not operate
within tolerances.
(e) Reduce the nitrogen pressure to zero and disconnect the nitrogen cylinder and
multimeter.
c. REMOVAL
1. Remove four screws retaining instruction plate and switch enclosure (2).
NOTE
Hold enclosure when removing hardware.
2. Remove two screws (3) and lockwashers (4) securing switches (5 and 6).
3. Carefully remove the switches (5 and 6) from the enclosure (2).
4. Pull sensing line through grommet.
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