Hydra-Electric Introduces Solution to Address Contact Resistance Problems in Aerospace Pressure Switches
New design alleviates the high failure rate of mechanical switches in engine systems and other aerospace applications. #aerospaceengineer #aerospaceswitches
There have long been numerous problems associated with the micro switch, a key component within every pressure switch. It vibrates in high g-force environments, giving false readings (especially on engines). When it gets opened and closed many times, it welds, which results in a false reading of an "open" position. In a normally closed operation, gauling and fretting can occur, creating high contact resistance and causing failures.
"It's one of the top issues we hear about—a mechanical switch will fail sooner than one would like after a certain number of cycles, especially in high vibration environments,"
Hydra-Electric's design incorporates a circuit board that senses the switch closure and makes it look like a constant impedance. It simulates the contact resistance that is seen, so that the output will not show the contact resistance and it will not be acted upon. As result, it provides dynamic impedance correction over the life of the switch.
The solution can enhance any Hydra-Electric standard pressure switch, and offers other advantages as well. It can modify the logic in the switch itself. It can set it to always open or always closed. Putting in a time delay, or filtering out the contact bounce are some of the many different features that can be added. In addition to the high vibration environment of engine systems, the solution is valuable for applications throughout the aircraft.