Testing The Regulator/Rectifier; Testing A Commutator Generator - Rothewald 10002567 Instrucciones De Uso

in the VΩmAhFE jack, and the black test lead in the COM jack on
the multimeter. Select the 200 ohm measuring range and hold
the test probes against each other for the continuity test until a
value of 0.1 – 0.3 ohm is indicated. Now hold the black test probe
against earth and the red probe against all the plug contacts one
after the other. There must be no measurable continuity (infinite
resistance), otherwise the stator would have a short circuit to
earth. Then use the test probes to test all possible combinations
for connecting the contacts – the resulting value should always
remain slightly less than 1 ohm. If the measured value is too high,
this indicates insufficient continuity between the windings, while a
measured value of 0 ohms would indicate a short-circuit. In both
cases the stator would be faulty. If the AC voltage at the alternator
is considerably too low despite the fact that the alternator windings
are undamaged, it can be assumed that the rotor is demagnetised.

6.1.3 | Testing the regulator/rectifier

If a charging voltage of more than 15 V is measured at the battery
when the engine is running at high revs, the voltage regulator is
either faulty (see above) or needs to be re-adjusted (some older
regulators are adjustable). A rectifier should be disconnected from
its circuit before testing. Insert the red test lead in the VΩmAhFE
jack, and the black test lead in the COM jack on the multimeter.
Select the 200 ohm measuring range. Hold the test probes against
each other for the continuity test until a value of 0.1 – 0.3 ohm
is indicated. Now the resistance between the rectifier's earth
cable and all the alternator connections, and also between the
positive output cable and all connections, must be measured in
both directions (in other words, reverse the polarity once in each
case). One direction should produce a low reading, while the other
direction should produce a reading at least 10 times higher. If any
of these connections produces the same value in both directions
(i.e. despite reversing the polarity), this indicates that the rectifier is
faulty and must be replaced.

6.1.4 | Testing a commutator generator

Commutator generators do not use permanent magnets to induce
current; instead they use the electromagnetic energy from an
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