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 d. Run the full-load Test at 5000 RPM. Increase load to the rated output +/- 10% and refer to Table 2-5. Table 2-5. FULL-LOAD TEST DIAGNOSIS AMPS VOLTS DIAGNOSIS HIGH LOW TEST BENCH BATTERY DISCHARGED OF DEFECTIVE. ALLOW TO CHARGE OR REPLACE. HIGH NORMAL CHARGING SYSTEM OKAY. HIGH HIGH STOP TEST. REGULATOR AND /OR FIELD COIL MUST BE REPLACED. GO TO STATIC TESTS. LOW LOW GENERATOR AND/OR REGULATOR MUST BE REPAIRED OR REPLACED. LOW NORMAL INCREASE LOAD LOW HIGH STOP TEST. BENCH MALFUNCTION OR WIRING ERROR. 2-8. STATIC TEST PROCEDURES a. Perform static tests on the partially disassembled generator to confirm component failure indicated by On-Vehicle test and bench tests. b. Complete all static tests before repairing and assembling the generator. c. Remove pulley and rear housing to perform the following checks in accordance with paragraph 3-4b, steps 1 thru 6. d. Refer to ohmmeter readings on multimeter. e. Static Checks: (1) Output Transistor - Do not check output transistor. If dynamic test indicates regulator or field coil failure and field coil is good, replace the regulator. (refer to step 3, field coil) (2) Clamping Diode - [1] Set ohmmeter to X100 scale and make sure ohmmeter is zeroed. [2] Disconnect the regulator. [3] Connect one multimeter lead to pin E. [4] Connect the other lead to pin B and observe ohmmeter reading. In one direction the ohmmeter should read less than 600 ohms, in the other direction the ohmmeter should read very high. If ohmmeter reads less than 600 ohms in both directions (short) or very high in both directions (open) clamping diode is defective and regulator must be replaced. Change 1 2-19