TM-9-2320-280-34 HMMWV Direct Support & General Support Maintenance Manual Download
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TM 9-2320-280-34 Change 1 6-18.33 6-3.3. 100 AMPERE DUAL VOLTAGE ALTERNATOR (12447110) TESTING AND REPAIR (Cont’d) 10. Alternator speed and current output tracking values. Refer to table 6-A.5. CONNECT DISCONNECT DIAGNOSIS AMPS RISE AMPS FALL Alternator OK. See note. Replace regulator only if low AMPS (40-59)/low VOLTS (21-25) are indicated in table 6-A.3 and/or table 6-A.4. NO CHANGE NO CHANGE Alternator must be repaired. Refer to static testing, task c. Table 6-A.6. Regulator Bypass Test. 11. Perform regulator bypass test. Prepare alternator as in full-load test. NOTE • Perform this test only when instructed from tables 6-A.3 and 6-A.4. • Use jumper wire rated for 15 amps. 12. Disconnect alternator connector from regulator. With alternator spinning, use jumper wire and short pin A to ground momentarily. Record results. 13. Amperage should rise within ± 10 percent of rated value with jumper wire connected, and fall with jumper disconnected. Refer to table 6-A.6, Regulator Bypass Test, for diagnosis. 14. Turn test stand master power switch and load switch to OFF. 15. Disconnect jumper wires from terminals on test stand and alternator. 16. Remove belt from test stand pulley and alternator pulley. Remove alternator from test stand. ALTERNATOR 28 VDC 14 VDC SPEED OUTPUT CURRENT OUTPUT CURRENT (RPM) ±5 AMP MINIMUM AMP 25 36 2000 38 43 52 33 65 20 **85 0 *0 8 4000 25 32 to 48 52 8000 70 30 87 13 **100 0 Table 6-A.5. Alternator Speed and Current Tracking. * Dependent on ammeter location in test circuit. **Minimum acceptable current with no load on 28 VDC system. ALTERNATOR 28 VDC 14 VDC SPEED OUTPUT CURRENT OUTPUT CURRENT (RPM) ±5 AMP MINIMUM AMP *0 26 10 31 1,200 25 23 35 13 48 0 *0 23 15 34 1,500 32 37 55 14 69 0 2,000 *0 20