ARMY TM 9-6115-464-34
AIR FORCE TO 35C2-3-445-2
NAVY NAVFAC P-8-624-34
(f) Read and record both voltmeter readings.
(g) With the oscillograph recording and the circuit interrupter closed, close the switch. (See figure
512.3-I.
(h) Reactivate the shutdown provision if used.
(i) The generator set contains an ovewoltage malfunction indicator; check and record its indication.
(j) Record whether or not the set shuts down.
(k) Open the switch, reset the ovewoltage circuit if necessary, restart the set if required, and close the
circuit interrupter.
(1) Repeat steps (e) thru (k) above two additional times.
d. Procedure II (Undervoltage).
(1) Preparation for test.
(a) Locate the input terminals of the undervoltage sensing circuit and connect the apparatus as
illustrated in figure 512.3–I.
(b) Repeat step (b) of para. 4-20c. (1) (b).
(2) Test.
(a)
(b)
(c)
(d)
(e)
(f)
(9)
(h)
(i)
Start and operate the set at rated frequency and no load.
Close the switch (see figure 512.3–I) and use the resistance, R1, to adjust the voltage to the rated
value.
Open the switch and adjust the resistance, R2, until Voltmeter No. 2 reads the undervoltage value
specified in table 4-1. This test shall be repeated for each undervoltage value.
Repeat steps (b) and (c) above to assure that the specified undervoltage and rated voltage settings
are correct.
Set the oscillograph chart speed such that the individual waveform peaks are clearly visible. Set the
timing lines to a minimum of 0.01 seconds per line or use a 60 Hertz timing trace. With the switch
open, adjust the trace peak–to-peak amplitude to a minimum of one inch (or 25 millimeters).
With the set operating and the circuit interrupter and the switch open, read and record both
voltmeter readings.
Close the switch and circuit interrupter.
With the oscillograph recording, open the switch.
After allowing sufficient time for the circuit interrupter to operate, check and record the indication of
the undervoltage malfunction indicator.
(j) Close the switch and close the circuit interrupter.
(k) Repeat steps (e) thru (j) above two additional times.
(l) Repeat (a) thru (k) for the other undervoltage value specified in para. 4-1.
4-20
