The Arm Disarm (AD) Switch is an electro-mechanical safety device that provides reliable safing and arming of an ordnance system by breaking the electrical path between source and an initiator element. Its function is similar to that of a Safe and Arm Device; however, it does not contain an explosive train.
The AD switch operates in response to electrical commands to physically rotate the internal rotary switches and can be designed to accommodate as many signals as required by the application. In the safe position, the rotary switch is open, the visual indicator is displaying a white “S” on a green background. In the armed position, the rotary switch is closed, the visual indicator is displaying a black “A” on a red background.
The AD Switch design includes a Safing Key which, when manually engaged, keeps the rotating assembly in the safe position while preventing inadvertent transfer from Safe (Disarmed) position to the Armed position. The Safing Key cannot rotate the device to the armed position nor does it have to pass though the armed position to safe the device. The key cannot be removed when arm power is applied to provide additional safety. The Safing Key can be engaged at any time; it will simply reverse any existing rotational motion, returning the AD Switch to the safe position (if not already there) before it is locked in place.
In summary, the integrated safety elements of the AD Switch provide:
- A positive mechanical lock that prohibits the safing and arming mechanism from moving to the “arm” condition, allows for manually safing of the of the AD Switch.
- Monitoring switches that provide “safe” or “armed” telemetry for the AD Switch.
- A visual status indication of the “safe” and “armed” status of the AD Switch.