INSTALLATION AND TROUBLESHOOTING INFORMATION FOR MODEL A31
PAGE 12 OF 15
G.
LED 2, low voltage shutdown when lit.
H.
LED 3, high voltage shutdown when lit.
NOTE: An open fuse on this board indicates a defective board.
A31 drive/snubber printed circuit board (S2A-165), (S2A-306) & (S2A-297)
A.
Need special test equipment, recommend sending printed circuit board to the factory.
B.
An open fuse on the S2A-165 board indicates defective transistor modules. An open fuse on the
S2A-297 or S2A-306 cards indicate a defective IGBT driver card.
Transistor modules.
R1 or R2 open, defective transistor modules.
The procedure for checking the transistor modules is as follows:
(DISCONNECT THE TRANSISTOR TO BE CHECKED)
Base to emitter, low resistance in both directions, but not zero ohms.
Base to collector, low resistance in one direction, high resistance in the other direction.
Emitter to collector, low resistance in one direction, high resistance in the other direction.
Transistor Number 1 collector to Transistor Number 2 collector twice the DC input voltage. (With
the inverter running)
To check units with the IGBT Modules.
With an ohmmeter, measure the resistance between Terminal 1 (collector) and Terminal 2
(emitter) negative lead on Terminal 1 should read, low resistance. Reverse the meter leads and
it should read a high resistance.
With negative lead on one, measure to Terminal 3, it should read high resistance.
With negative lead on Terminal 1, measure to Terminal 5, it should read a low resistance.
When the S2A-297 or S2A-306 card is removed, jump the gate and emitter of the IGBT with
copper wire to protect from ESD damage.
C1, Resonating Capacitors 560 Vac - 660 Vac (approximately)
With an analog ohmmeter, R x 10,000 scale, you should see the meter deflect to low resistance, then
gradually rise to high resistance.
Electronic Transfer Switch (S2A-139A)
A.
Pin Number 2 positive DC input, Pin Number 1 negative DC input.
B.
Pin Numbers 4,5,6,7 and 8 an oscilloscope is required to see the switching of the SCR’s.
Status Light Panel (S2A-147)
A.
Pin Number 1 positive DC input voltage, Pin Number 2 and 3 negative DC input voltage.
B.
Pin Number 6 neutral, Pin Number 7 AC bypass phase.
C.
Pin Number 8 inverter output neutral, Pin Number 9 inverter output phase.
No AC voltage output.
A.
Check the F1 and F2 fuse, if open refer to previous possible causes.
B.
Check DC input, look at the rectifier.
