Table 3-9. Sensors DS Maintenance Troubleshooting

TM 5-6350-275-24&P

Table 3-9. Sensors DS Maintenance Troubleshooting

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

1. BALANCED MAGNETIC SWITCH FAILURE (Figure 3-10)

Step 1. Ensure door, window, vent, or type of entry being protected is properly closed or fastened and all

mounting hardware is present and tightened down. Check gap between magnet and sensor unit to

ensure it is within specified distance according to model number of BMS sensor.

If sensor is still in alarm, go to step 2.

Step 2. Remove the sensor input cable from the Leda Flex Termination PWA or Stargate PWA termination

board. Go to sensor output cable assembly interface terminal strip and remove cover. Using a multimeter,

place function switch to ohms. Place black lead from multimeter on common lead (6). Place red lead from

multimeter on closed loop lead (4). The multimeter should read continuity with door closed.

If meter does not show continuity, replace BMS (Para. 3-111, 3-112, or 3-113).

If meter shows continuity, go to step 3.

Step 3. Open portal to unbalance the BMS. The meter should change from a continuity indication to an open

circuit indication.

If indication is correct, the BMS is good, or if the BMS has a tamper switch, go to step 4.

Step 4. Place black lead from multimeter on Supervised common lead (7). Place red lead from multimeter on

Tamper lead (8). The multimeter should indicate continuity.

If multimeter does not indicate continuity, replace the BMS (Para. 3-111, 3-112, or 3-113).

If multimeter indicates continuity, the BMS is good. Go to troubleshooting steps for the RADC (Table 3-

3).

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