Ametek Silicon Diode Ferroresonant Transformer Type Battery Charger 750H3-12E

Turn OFF and remove fuses of disconnect switch supplying AC power to charger

Check for voltage on capacitors

Is there any voltage reading on capacitors?

Discharge capacitors through insulated screwdriver if there is any reading

Disconnect one diode lead to isolate diode from electrical circuitry

Use a good quality ohmmeter to measure resistance values

Heed WARNING in Silicon Diode Testing section

Connect leads of ohmmeter to capacitor terminals

Observe ohmmeter pointer deflection

Does the pointer deflect indicating charging?

Does the pointer deflect in the opposite direction indicating partial discharge?

If there is no deflection, replace the capacitor

If the meter needle moves and stops at one value, replace the capacitor

Electrical Connections Inspection

Check and tighten all electrical connections

Check for broken wiring or damaged insulation on wiring

WARNING: ELECTRICAL SHOCK HAZARD

Ensure internal parts are clean and dry to prevent transformer shorting

Replace all charger cabinet panels after servicing to ensure proper cooling and protection

Ensure the charger is turned off and unplugged

Gather cleaning materials (clean, dry air source or hand bellows)

Check air pressure (should not exceed 25 psi or 172 kPa)

Wipe all accessible surfaces of the unit with a clean, dry cloth

Blow out dirt from the unit's interior components using clean, dry air or hand bellows

Is the unit clean, dry, and well ventilated?

Ensure no bad connections or damage to charger is affecting the charging process.

Verify proper charging procedure has been followed.

Turn OFF and remove fuses of disconnect switch supplying AC power to charger.

Check for voltage on capacitors.

Is there any voltage reading on capacitors?

Discharge capacitors through insulated screwdriver if there is any reading.