What is the difference between Maintained and Momentary Contact?
Maintained Contact (MA) A switch that physically keeps the button and circuit in the actuated position, open or closed. In other words, when the key or push switch is actuated it stays in the ON or OFF position until actuated again. An example of a maintained contact device is a light switch. Another form of ON/OFF switch contact is called Alternate Action (AA). An Alternate Action contact device keeps the circuit in the actuated position even after the button returns to its normal position. Pressing the switch button again causes the actuated contact to release and the button returns to its normal position. Applications: Maintained contact and alternate action ON/OFF switch applications include: Locking or unlocking a single door, zone of doors or complete system for an indefinite period of time. Momentary Contact (MO) A switch that opens or closes the circuit only when it is actuated and then immediately returns to its normal position when. An example of this is a desk switch. While
