TM-9-1200-215-34&P Technical Manual for M109 Automatic Fire Control System (AFCS) Download
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TM 9–1200–215–34&P 6–3 Section IV – MANUAL TROUBLESHOOTING. Page Page General 6–3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Functional Description 6–3 . . . . . . . . . . . . . . . . . . . . . Troubleshooting Procedures 6–8 . . . . . . . . . . . . . . . . Post–Maintenance Test 6–8 . . . . . . . . . . . . . . . . . . . . 6–8. GENERAL This chapter contains information on checks and corrective actions required to isolate defects in the Power Conditioning Unit (PCU), and correct the defects by means of maintenance. The troubleshooting shall begin with a fault or symptom and lead to a single fault isolation of the problem. In cases where the maintenance must be performed at a higher level, the description will note “Forward PCU to Depot”. 6–9. FUNCTIONAL DESCRIPTION a. The Power Conditioning Unit (PCU) provides conditioned (filtered and supported) power to the AFCS plus unconditioned (unfiltered and unsupported) power to components outside of the AFCS. The PCU utilizes 14 volt storage batteries (back–up batteries) to supplement host vehicle power to the AFCS. A block diagram of the PCU is shown in Figure 6–1 below. J4 50A J7 RADIO RACK 15A 20A 10A 20A 10A J6 J8 IR/NS LEU IR/NS OUTPUT LEU OUTPUT RADIO OUTPUT BACKUP BATTERY J5 DIAG– NOSTIC PORT POWER BUS A POWER BUS B 20A 20A J1 J2 VOLTAGE DOUBLER RELAY J3 BACKUP BATTERIES BATTERY CHARGER MONITORS AND CONTROL AND NUCLEAR EVENT DETECTOR 40A 40A VEHICLE POWER RELAY EMI FILTER EMI FILTER 28V CONDITIONED RETURN 28V CONDITIONED POWER 28V UNCONDITIONED POWER 28V UNCONDITIONED RETURN Figure 6–1. PCU Block Diagram