How can you tell if a switch is momentary or maintained/latching?

To determine whether a switch is a momentary or maintained (latching) switch, you can use the following methods:

1. Labeling and Markings:

Momentary Switch: May have markings indicating "NO" (normally open) or "NC" (normally closed) with "MOM" to indicate its momentary nature.

Maintained Switch: Often labeled with "ON/OFF" or "I/O" without "MOM" or similar markings.

2.  Physical Testing

Momentary Switch: Press the switch and release it. If the switch returns to its original position when released, it is a momentary switch. Momentary switches are often used in applications where a brief connection is needed, such as a doorbell or keyboard key.

Maintained (Latching) Switch: Press the switch and release it. If the switch stays in the new position after being pressed (e.g., staying on or off), it is a maintained switch. These are commonly used for lights, where the switch stays on until pressed again.

3. Electrical Testing

Momentary Switch: Use a multimeter to test continuity. If continuity is present only when the switch is pressed and breaks when released, it is momentary.

Maintained Switch: If continuity remains after the switch is pressed and only breaks when pressed again, it is a maintained switch.

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