variable load resistance until test ammeter indicates 40
1 percent or
amps and verify that voltage regulation is
better at the power supply TBI-3 and TBI-4, over the load
range. While load is being varied, verify that ammeter
(A) is accurate to within 2 percent of full scale as
compared with test ammeter when selector switch (S3) is
in the 50 amp position and the press to read switch (SW2)
is depressed. Connect an oscilloscope or peak to peak
meter between TJBP2 and TJBP5 and verify peak to peak
ripple does not exceed 200 millivolts at full load.
Adjust variable load for maximum resistance. Adjust DC
voltage for 26 volts on distribution box voltmeter and
verify that voltmeter (V) is within 2 percent of full
scale, as compared with test voltmeter. Decrease load
resistance until test ammeter Indicates 40 amps and
verify that voltage regulation is within
1 percent at
the power supply (TBI-3 and TBI-4). Verify that peak to
peak ripple does not exceed 200 millivolts. Adjust
variable load for maximum resistance.
Apply 230 VAC 3 phase 50 - 60 hertz to power cart AC
supply cable and repeat paragraphs c through e. above.
Adjust DC voltage output for 30 VDC and adjust variable
load for 65 amp output until 50 amp circuit breaker
trips, then adjust to maximum resistance. Verify that DC
breaker will reset.
Utilizing test voltmeter verify that 30 VDC is present at
the following points:
(1) TJBP2 to TJBP5
(2) TJBP3 to TJBP6
(3) Pin A to Pin B on J106 and J107
(4) Receptacle A to B on J103 (both positions)
(5) Pin P, O, R, J to Pins H and Y of J102
Verify continuity from TJ1 to Pin E of J102 and TJ2 to
Pin F of J102.
DC supply current limit test.
With power supply AC power cable disconnected, connect an
external 24 volt source, external load, and ammeter to
TB2 as shown in Figure 1.
b. Connect power supply AC power cable to 220 VAC 3 phase 50
to 60 Hertz supply. Connect power supply connectors P105
and P104 to distribution box receptacles J105 and J104.
Energize power supply and adjust output to 28 VDC,
distribution box voltmeter can be used.
c. Starting with external load resistance set at maximum,
increase current through resistor (R10) until start of
current limit and continue until voltage output is 1 volt
maximum. Verify that observed ammeter readings are in
compliance with 3.17.4.b.(3).(b).