Use MID400 power line monitor

The MID400 is an optically isolated AC line-to-logic interface device for monitoring on or off status of an AC power line. The logic circuitry operates from a standard 5V supply. The MID400 is packaged in a compact 8-pin plastic DIP. The optical isolation provided by the MID400 makes it suitable for power-to-logic interface applications such as industrial control, medical equipment, computers and other fail-safe type monitor systems in which status information about the AC line is essential.

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