FENCE-MOUNTED VIBRATION SENSOR FAILURE

TM 5-6350-275-24&P

Table 3-9. Sensors DS Maintenance Troubleshooting - Continued

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

11. FENCE-MOUNTED VIBRATION SENSOR FAILURE (Figure 3-20)

NOTE

Refer to the SAIG for details on the fence-mounted vibration sensor.

Step 1. Remove front cover from processor assembly (1) and make a visual inspection of fuse (9) to see if the

fuse is blown.

If fuse is blown, replace fuse and go to step 3.

If fuse is not blown, go to step 2.

Step 2. Set multimeter to read vac and place multimeter leads across TB1 pins 1 and 2. The multimeter should

read 12 vac.

If multimeter reads 12 vac, go to step 3.

If multimeter does not read 12 vac, replace input power source.

Step 3. Reset alarm by pressing RESET switch (5) up, then releasing.

Step 4. Remove green wire from terminal board (7) pin 6. This should produce a pulsing tone, and alarm relay

should also pulse, indicating line supervision system is working correctly.

If a pulsing tone is produced, line supervision system is working correctly. Reconnect green wire to TB1

pin 6.

If a pulsing tone is not produced, replace the processor PWA (Para. 3-117).

If system is still in alarm, go to step 5.

If system in not in alarm, close and secure processor assembly (1) cover and have workstation operator

verify that system alarm has been cleared.

Step 5. Have someone, starting at far end of sensor line (8), lightly tap each individual sensor (2) with tip of a

screwdriver. The activity light (3) will go on to indicate that sensor is operating. Perform this step until

faulty sensor is located.

Remove and replace faulty sensors (Para. 3-118).

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