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Diode Trio Test

  1. Remove diode trio from end frame. Connect an ohmmeter to single connector and to one of the 3 connectors. See Fig 1. Note reading and reverse leads.
  2. A good diode trio will give a high and low reading. If readings are the same, replace diode trio. Repeat tests between single connector and each of the 3 connectors.
NOTE: Before replacing diode trio, also check rectifier bridge. Do not use high voltage, such as 110-volt test lamp, when testing diode trio.
Fig 1: Bench Testing Diode Trio Test diode trio using an ohmmeter.
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