Lamarche A36F Instructions Manual - page 15
A36F - 3 PHASE - INSTRUCTIONS AND TROUBLESHOOTING
Page 15 of 21
5. Shorted C3 capacitors.
6. Loose connections on the d.c. fuse.
12.3.3
Charger operates but output voltage/current is low.
Possible Cause:
1. Float/Equalize voltage potentiometers not set correctly (see float/equalize adjustment procedure for
proper voltage setting).
2. Check power diodes or diode modules and triac (see diode and triac troubleshooting procedure).
3. Regulator assembly or “informer” is defective. (Replace as required)
4. Defective d.c. voltmeter/ammeter.
5. Unit in current limit.
6. Resonating capacitor open.
7. Defective shunt.
12.3.4
Charger operates but output voltage is high.
Possible Cause:
1. Float/Equalize voltage pots not set correctly (see float/equalize adjustment procedure for proper
voltage setting).
2. Circuit regulator assembly S2A-188 is defective.
3. Open gate on triac TR-1.
12.3.5
Ground and short circuit test.
A simple ohmmeter check can be performed to check the unit for a short to ground, primary to secondary
breakdown, a.c.-d.c. short, or d.c. ground. Before installation of a new unit, the above checks should be
made before installing. If a short of this type is suspected on a unit in service, check as follows:
1. Disconnect a.c. input power to the unit. Disconnect the d.c. battery and loads from the rectifier.
2. Set ohmmeter scale on ohms scale RX100.
3. Measure from one terminal of the input to one terminal of the output. Meter should not indicate. If
the meter reads full scale deflection, this indicates an ac-dc short. During shipping, an a.c. wire may
rub against the d.c. lugs, terminals, etc. and cause a short. These problems may be eliminated by
very carefully inspecting the wiring to make certain the a.c. wires are not touching the d.c. wiring.
4. Check the input terminals to ground and check the output terminals ground. If the meter indicates
full scale deflection, a wire is touching a metal part of the rectifier. Look for wires that are near any
metal part and inspect for possible breakdown caused by shipping. The heatsink of the diodes and
the control unit are insulated from ground through the mounting legs.