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Testing (On Car)

CAUTION: When making test connections, make certain ignition is OFF to prevent damage to regulator.
  1. Make up a test switch tool by connecting leads to a simple "on-off" switch and connect this switch in series with lead removed from regulator IGN terminal. Connect postive terminal of test voltmeter to regulator lead terminal of on-off switch and ground opposite voltmeter lead. Connect 0-50 ampere ammeter in series with lead removed from alternator BAT terminal. Connect a carbon pile rheostat across battery terminals to vary load (or turn on lights and accessories to accomplish this result).
  2. Start engine and operate at 1250 RPM, adjust carbon pile or lamp load for 15 ampere output as registered on test ammeter.
    NOTE: No ammeter reading indicates low setting on regulator or blown fusible wire and this condition must be corrected before proceeding with test.

    Operate engine at 1250 RPM with 15 ampere load for 15 minutes to normalize system temperatures.

  3. Upper Contact Test  - With temperature normalized, readjust engine speed to 1250 RPM and alternator output to 15 amperes. Note and record ambient temperature using accurate thermometer at a distance of 1/4" from regulator cover. Flash regulator by opening and closing on-off switch several times, then note voltage as indicated on test voltmeter. If voltage not within range for indicated temperature (see Specifications), remove regulator cover and adjust regulator (see ADJUSTMENT ).
  4. Lower Contact Test  - Increase engine speed to 2200 RPM, adjust carbon pile (or turn off all lamps and accessories) to decrease output to 7 amperes as indicated on test ammeter. Voltage should increase. Recheck ambient temperature at regulator cover with thermometer to make certain it has not changed. Flash regulator by opening and closing on-off switch several times, then note voltage as indicated on test voltmeter. Voltage should not be less than.2 volt or more than.7 volt than voltage noted on Lower Contact Test at same ambient temperature (step 3 above). If voltage increase not within these limits, air gap or contact gap is not within specifications and should be adjusted (see ADJUSTMENT ).
    NOTE: Voltage at engine speeds above 2200 RPM will be slightly higher but must not be more than.7 volt higher at any temperature range.

    If voltage less than.2 volt higher, check battery and make certain it fully charged.

  5. After tests completed, stop engine, disconnect battery and remove all test equipment, restore and tighten all regular circuit connections, then reconnect battery.
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