the wire end clear of the frame and engine).
Connect one test lead to rectifier brown terminal, the other test lead
to earth.
Switch on to EMG and run the engine at tickover when, if the rectifier
is O.K., the bulb will light brightly (six coils in circuit).
Repeat the test with the switch at IGN {three coils in circuit), the bulb
will light, but not so brightly if rectifier is O.K.
Warning: Do not attempt to run the engine with an open circuit for the
rectifier. The brown wire or the test set must be connected to prevent
high voltage which will cause damage.
Rectifier (reverse flow test). With the light and ignition switches 'OFF'
test by:
Taking off one of the battery wires from the battery.
Connect the test set with the .04 amp bulb between the battery terminal
and the battery wire.
If the reverse flow is normal, the bulb will light dimly, a bright Light
indicates a defective rectifier,
Alternative rectifier tests. An alternative method of testing can be effec-
ted by using the following equipment:
(1) A moving coil ammeter, scale 10-0-10.
(2) A fully charged 6 volt battery,
(3) A 6 volt 30 watt lamp bulb and holder.
(4) A 6 volt 0.04 amp bulb and holder.
(5) Three short test wire.
Forward flow test. Make a series circuit. The bulb will light with a read-
ing of approximately 4.5 amps on the meter.
Take off the wire from the positive battery terminal, connect the third
test lead to the positive battery terminal, also to the brown terminal on
rectifier (d.c. negative).
Take up the wire taken from the battery and connect in turn to the
green, then white, terminals (a.c. side).
In each test the bulb should light with a reading of 4,5 amps on the
meter.
For clarity, remove test wires from rectifier, remake the series circuit.
Next remove the battery negative wire, connect the third test wire to
the negative battery terminal, also to the rectifier earth bolt or case.
Connect in turn the wire removed from the battery to the green and
white terminals. Again, in each test the bulb should light with a reading
of 4.5 amps.
If the meter readings on these tests are above 3 amps, the rectifier is
satisfactory. Discard the rectifier if the readings are below 3 amps.
NOTE—Whilst a new rectifier will show 4.5 amps, this value will decrease
after considerable service.
Reverse flow test. Make a circuit using .04 amp bulb for this test.
A rectifier that is normal will have a reverse flow which should not
exceed 0.040 milliamps, by using the 0.40 bulb with a current consump-
tion of 40 milliamps it can be established if the reverse flow is abnormal
by:
Removing the positive lead from the battery.
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