TM 5-6115-593-34
NAVFAC P-8-631-34
TO-35C2-3-463-2
undervoltage value.
(d)
Repeat steps (b) and (c) above to
ensure
that
the
specified
undervoltage
and
rated
voltage
settings are correct.
(e)
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 Hz
timing trace. With the switch open,
adjust
the
trace
peak
to-peak
amplitude to a minimum of one inch
(or 25 millimeters).
(f)
With the set operating and the
circuit interrupter and the switch
open,
read
and
record
both
voltmeter readings.
(g)
Close
the
switch
and
circuit
interrupter.
(h)
With the oscillograph recording,
open the switch.
(i)
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) through (j) above
two additional times.
(l)
Repeat (a) through (k) for the other
undervoltage
value
specified
in
paragraph 16-1.
e.
Results.
(1)
From the oscillograms made in paragraph
16-20c determine and tabulate the time
between
the
application
of
the
overvoltage and operation of the circuit
interrupter
for
each
application
of
overvoltage.
(2)
From the oscillograms made in paragraph
16-20d determine and tabulate the time
between
the
application
of
the
undervoltage and the operation of the
circuit interrupter for each application Of
undervoltage.
(3)
Compare
these
results
with
the
requirements of table 16-1.
16-21. LOW OIL PRESSURE PROTECTIVE DEVICE
TEST.
a.
General. Since generator sets frequently
operate unattended for long periods, the engine
is equipped with a low oil pressure protective
device. This device shuts down the engine
when the oil pressure drops below the safe limit.
b.
Apparatus. The following equipment shall be
required to perform this test:
(1)
Oil pressure gauge (±1 percent)
(2)
Flexible oil line (or copper tubing).
(3)
Regulating valves
(4)
Brass fittings.
c.
Procedure.
(1)
Preparation for test. With set not
operating remove the protective device
tap from the engine block and reconnect
as shown in figure 515.1-I with the
protective device and oil pressure gauge
in approximately the same horizontal
plane as the protective device tap located
on the engine.
16-18
