TM-9-2920-257-30&P Maintenance and Parts Manual for 200 Amp M113 Generator Download
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TM 9-2920-257-30&P NOTE If regulator malfunction is indicated, field coil failure must also be suspected. (3) Field Coil (a) Disconnect both field coil leads F+ and F- from front housing (fig 2-14). (b) Open field coil - Set ohmmeter to X1 scale and make sure ohmmeter is zeroed. Measure resistance between field leads (+F and -F). Ohm reading should read less than 4 ohms. If ohms read 4 ohms or more, the field coil is open and must be corrected by replacing or repairing stator and shell assembly, in accordance with paragraph 3-4b, steps 1 thru 8. (c) Grounded field coil - Set ohmmeter to X10k scale and make sure ohmmeter is zeroed. Connect one multimeter lead to either field lead (F+ or F-). Connect the other multimeter lead to the front housing ground stud. The ohm reading should be very high. If the ohms read less than 100K ohms, the field coil is grounded and must be corrected by replacing or repairing stator and shell assembly, in accordance with paragraph 3-4b, steps 1 thru 8. Figure 2-14. Front Housing Connections 2-20 Change 1