Dual Pole Arming Sensor

The Dual Pole Arming Sensor is a protective switch located in the high side (power side) of the Deployment Loops. The Dual Pole Arming Sensor is calibrated to close at low velocity changes (lower than the Discriminating Sensors). This ensures that the inflator modules are connected directly to the "36 VLR" outputs of the DERM or ignition 1" voltage when any Discriminating Sensor closes.

The Dual Pole Arming Sensor consists of: a sensing element, two sets of normally open switch contacts, diagnostic resistors and diodes. The sensing element closes both sets of switch contacts when the velocity of the vehicle changes at a rate indicating a potential need for deployment.

Two of the diagnostic resistors are connected in parallel with the switch contacts. This allows a small amount of current to flow through each of the Deployment Loops during normal, non- deployment operation. This current flow results in voltage drops across each component in the Deployment Loops.

The DERM monitors these voltage drops to detect circuit or component malfunctions. There are two additional diagnostic resistors within the Dual Pole Arming Sensor which allow the DERM to monitor the voltage supplied to the high side of the Deployment Loops. These monitored voltages are used by the diagnostic logic of the DERM to make a more precise determination of the actual Deployment Loop malfunction.

The diodes within the Dual Pole Arming Sensor provide isolation between the "36 VLR" outputs of the DERM and the vehicle electrical system "Ignition 1" voltage. The presence of the diodes prevent a direct continuity measurement through the Dual Pole Arming Sensor resistors to terminals "A", "B", or "C".