Diode Trio
- Remove diode trio from end frame assembly. Connect an ohmmeter to single brush connector and to any of 3 stator lead connectors. Then reverse ohmmeter probes. See Fig 1 . A good diode will give one high and one low reading. If both readings are the same, replace diode trio.
- Repeat tests, touching leads in turn from single brush connector to each of the 3 stator lead connectors. Then, connect ohmmeter to each pair of 3 connectors. If any reading is zero, a short is indicated between diodes. Replace diode trio.NOTE: Before replacing diode trio, also check rectifier bridge. Do not use high voltage (110 volt) test lamp to check diode trio.