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Rectifier Bridge Test

  1. Connect an ohmmeter with one lead touching grounded heat sink and the other lead touching flat metal on 1 of the 3 terminals. Observe reading and reverse test lead connections. See Fig 1.
  2. If both readings are the same, replace rectifier bridge. A good bridge will give one high and one low reading. Repeat test on all terminals (6 tests with insulated heat sink).
  3. Connect test leads to insulated heat sink and 1 edge of the 3 terminals. Observe reading and reverse connections. Repeat test on all terminals (6 tests with insulated heat sink).
  4. When all 12 tests have been made, testing is complete. DO NOT  use a high voltage, such as a 110-volt test lamp to check the bridge. DO NOT  replace diode trio or rectifier bridge unless at least 1 pair of readings is the same (with leads reversed).
Fig 1: Bench Testing Rectifier Bridge & I.D. of End Frame Components Observe reading and reverse test lead connections.
G10032