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Rectifier Bridge Test

  1. Position ohmmeter with one lead touching grounded heat sink and the other lead touching flat metal on one 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 a high and low reading. Retest all terminals (6 tests with insulated heat sink).
  3. Connect test leads to insulated heat sink and one 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 high voltage lamp to check bridge. DO NOT  replace diode trio or rectifier bridge unless at least one pair of readings is the same (with leads reversed).
Fig 1: Bench Testing Rectifier Bridge Observe reading and reverse test lead connections.
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