TM 10-3930-671-24 RELD    EXCITATION    VOLTAGE    TEST    (22/30    Amp Systems)- Ammeter remains connected as in Figure No. 9.    Move  positive  voltmeter  lead  to  the  alternator  FLD., field  terminal  (Figure  No.    10).    Meter  should  read  zero volts.  Turn ignition switch on, voltmeter should read 2.0 to 3.0 volts.  Ammeter should show a slight discharge .1 to   .3   amperes,   if   other   electrical   accessories   are   not operating.  If the voltage is higher than 3.0 volts.  the field circuit is defective. The  regulator  circuit  may  be  checked  by  disconnecting the field lead from the field terminal.  Connect voltmeter positive lead to the field lead, voltmeter should read 8 to 12 volts, indicating that the difficulty is in the altemator. If the voltmeter reads zero volts in either step, check regulator connecting plug, ignition switch, charge indicator lamp and all related wiring.  If correct readings are obtained, or after correction of fault, proceed with next step. FIGURE NO.  10 F-278