Momentary Switch

A type of switch usually in the form of a push button that is only engaged while it is being depressed, as opposed to a typical “on/off” switch, which latches in its set position. Momentary switches may be normally open or normally closed. A normally open switch doesn’t make contact until and unless it is held down. A normally closed switch is always making contact until the button is pushed. Most electronic keyboard sustain pedals use momentary switches. Unfortunately most manufacturers never agreed on a standard for normally open or normally closed so your Yamaha switch may not work with your Korg keyboard, and vice versa. (This is less of an issue these days as most synths automatically set themselves for the type of switch connected upon power up.)