Troubleshooting Guide
7
31039B
interruptions, plug an electric clock into the same
outlet to which the AC cord is connected. Charge
normally and note any time difference between the
test clock time and the actual time.
SECTION 6 – AC LINE FUSE OR CIRCUIT
BREAKER BLOWS
If this occurs when the charger power supply cord is
connected to an outlet, without the DC output
connector connected to the battery connector, the
charger power supply cord may be shorted.
Disconnect the power supply cord from its outlet and
the DC output connector from the battery connector,
then check to be sure the Electronic Timer Kit is
NOT bypassed. With a suitable continuity tester,
check the circuit across the power supply cord
prongs. THE CIRCUIT SHOULD NOT BE
COMPLETE. If the circuit is complete, check the
relay contacts to be sure they are open and have not
welded closed. If the relay contacts are open, the
power supply cord is shorted and must be replaced.
If the power supply cord checks good, the
transformer coils may be shorted. Refer to Section
7, "Transformer Short or Burn-out", for test
procedures.
SECTION 7 – TRANSFORMER SHORT OR
BURN-OUT
Failure of the transformer can be the result of natural
aging, premature shorting of adjacent coil turns or
overheating damage. The most common cause of
transformer overheating and premature burn-out is
the result of misuse, connecting the charger to a
battery system of lower voltage than specified on the
charger (see Section 3). Darkening of all the
transformer secondary coil windings is an indication
of possible overheating damage. A low or complete
lack of output would be observed on the ammeter;
however, the transformer may hum or the AC line
fuse or circuit breaker may blow when the charger is
turned on. To test the transformer, disconnect the
power supply cord from its outlet and the DC output
connector from the battery connector. Then
disconnect the transformer secondary coil leads #1
and #4 from the diode terminals and disconnect the
transformer capacitor coil leads from the capacitor
terminals. Use care when disconnecting the
capacitor lead so the wires do not break.
DANGER: HIGH VOLTAGE! WITH THE
CHARGER OPERATING, THE CHARGER
CAPACITOR VOLTAGE IS APPROXIMATELY 650
VOLTS AC. USE EXTREME CAUTION WHEN
WORKING NEAR THE CAPACITOR TERMINALS.
In order to apply AC power directly to the
transformer primary coil, the Electronic Timer Kit
must be bypassed. Refer to Section 1, Part A, for
bypass procedures. With the Electronic Timer Kit
bypassed and taking care of personal safety,
connect the power supply cord to an outlet. If the
AC line fuse or circuit breaker blows, the transformer
is shorted internally and must be replaced. If this
does not occur, check the transformer secondary
and capacitor coil voltages (Figure 1), using a
suitable AC voltmeter. If the measured voltages are
substantially lower than those shown, the
transformer is shorted internally and must be
replaced.
If the transformer secondary coil voltage and
capacitor coil voltage check good, disconnect the
power supply cord from its outlet. Check the
capacitor for correct rating, and then carefully
reconnect the capacitor coil leads to the capacitor
terminals. Then, taking care for personal safety,
reconnect the power supply cord to an outlet and
measure the transformer secondary voltage again.
The correct voltage reading for a 36 VDC charger is
shown in Figure 2. If the transformer secondary
voltage is the same as measured with the capacitor
disconnected, the capacitor may be opened, the
capacitor coil may be open, or the capacitor coil
terminals may not be making proper electrical
contact. Refer to Section 1, Part C, Item 2, for
capacitor test procedures. If the voltage readings
are correct, both the transformer and capacitor are
good, refer to Section 1, Part C, Item 1, for further
tests of the DC circuit.
If it should become necessary to replace a terminal
on one of the transformer leads, the new terminal
must be crimped AND soldered. NOTE: Some
transformer leads may be aluminum wire and a
solder must be used on these wires that is intended
for use on aluminum, such as Alcoa #807 solder
with Alcoa #69 flux. If these materials are not
available locally, contact the Lester factory.
LESTER ELECTRICAL, INC.
625 West A Street
Lincoln, NE 68522-1794 USA
Attention:
Service Department
Telephone: 402 477-8988
Fax:
402 474-1769
E-Mail:
