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Current Output Test

CAUTION: Generator has 2 field terminals: generator field driver (Dark Green wire) and generator field source (Dark Green/Orange or Dark Green/Violet wire). DO NOT  connect generator field source terminal to ground.
NOTE: Perform VOLTAGE DROP TEST  before continuing with this test. Perform test soon after starting engine, as charging amperage will drop quickly. A volt/amp tester equipped with both a battery load control (carbon pile rheostat) and an inductive type pick-up clamp is required to perform the following test.
  1. Ensure battery is in good condition and is fully charged. Clean battery terminals (if necessary). Connect volt/amp tester leads to battery. Ensure carbon pile is in OFF position before connecting leads. Connect inductive pick-up clamp.
  2. Connect tachometer to engine. Start engine and raise engine speed to 2500 RPM. Slowly adjust rheostat control (load) on volt/amp tester until highest amperage reading is obtained. DO NOT  allow voltage to drop less than 12 volts.
    NOTE: Depending on volt/amp tester manufacturer, load may be applied automatically. Refer to volt/amp tester manufacturer's instructions.
  3. Note reading on ammeter. Generator amperage reading should be more than the minimum amperage rating specification. See GENERATOR SPECIFICATIONS . If amperage reading is less than minimum specification, go to step 5). If amperage reading is more than minimum specification, go to next step.
  4. Rotate load control knob to OFF position. Continue to hold engine speed at 2500 RPM. Output amperage should change to less than 20-amps, indicating EVR circuitry is okay and charging system is functioning properly. It may take several minutes for amperage to change. If output amperage does not change to less than 20-amps, perform TEST TC-11A: GENERATOR FIELD  NOT SWITCHING PROPERLY under SELF-DIAGNOSTIC TESTS.
  5. Connect a jumper wire between ground and generator field driver terminal (Dark Green wire) on back of generator. Start engine, and immediately reduce engine speed to idle. Adjust carbon pile and engine speed in increments until engine speed is 1250 RPM and voltmeter reads 15 volts. DO NOT  allow voltage to exceed 16 volts.
  6. Note reading on volt/amp tester. Generator amperage reading should be more than the minimum amperage rating specification. See GENERATOR SPECIFICATIONS . If amperage reading is less than minimum specification, replace generator. If amperage reading is more than minimum specification, a fault exists in the EVR circuitry. Perform TEST TC-11A: GENERATOR FIELD NOT  SWITCHING PROPERLY under SELF-DIAGNOSTIC TESTS.
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