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Diode Trio

  1. Remove diode trio from end frame assembly. Connect one ohmmeter lead to brush connector and second lead to one of 3 stator lead connectors. Reverse ohmmeter probes. See Fig 1. If one high and one low reading is obtained, diode trio is okay. If readings are identical, replace diode trio.
  2. Repeat test, touching leads in turn from single connector to each of 3 stator lead connectors. If any reading is zero, a short is indicated. Replace diode trio. Check rectifier bridge before replacing diode trio.
Fig 1: Bench Testing SI Series Diode Trio
G3505