AnsaldoSTS F-42, Установка, эксплуатация и обслуживание

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PARTS LIST
SM 5924, Rev. 1, June 2009 4-3
6. Place a scope (dc operation) across the base and emitter of Q1. Observe that not less than 1V
and not more than 2V reverse bias is being applied during the off time of Q1. The bias
circuit, consisting of diode D3 and leads 1S and 2S of transformer Tl, must be operational
before loads can be applied to the converter. The bias voltage should vary between 1V and
2V over the voltage range of 40 to 80 volts.
7. If all tests for the pre-regulator section are acceptable, remove all test equipment and the
power supply from the pre-regulator section circuits and proceed to check out the output
section in paragraph Section 4.3.
8. If the foregoing requirements are not met, proceed to check out boards CB1 and CB3 (pre-
regulator section) in accordance with Sections 4.4 and 4.5.
4.3 CONVERTER OUTPUT SECTION
1. Disconnect terminal TP7-1 (as indicated in Step 1 of Section 4.2). This separates the pre-
regulator section from the output section.
2. Connect a variable do power supply (approximately1 amp, 50 VDC maximum capacity)
across tie point TP7-1 and the DC input terminal or between the emitter of Q4 and the
collector of Q5.
3. Place a scope across the + lS and 2S leads of the out-put transformer T3 (the AC input
terminals of rectifier BR1).
4. Slowly increase the input voltage from 0V to 10V and observe that the output waveform
1S and 2S is a symmetrical square wave without spikes. The input current should not
exceed 0.2 amp at the 10 VDC input level.
5. If Step 4 is satisfactory, increase the input voltage to 32V. The DC output voltage should be
approximately 33.2V and the input current approximately 0.520 amp.
6. If the preceding requirements are not met, proceed to Section 4.6 and check out CB2
accordingly.
7. If both sections of the power supply meet test specifications, connect terminal TP7-1 and re-
calibrate the unit according to the calibration paragraph (Section 3.3).
Anytime
a
board
is
replaced, the unit must be re-calibrated.
Boards found to be faulty, should be returned to ASTS USA for adjustment and repair.
4.4 CBI – Electronic Control Board (N451120-4101)
The function of this control board (Pre-regulator Section)
is
to sense the pre-regulated voltage and
to trigger the input gate as required to hold regulation. Q1 controls the gate (through external