magnetic switches

7426 looks like the date code ( year and week ).

Probably power + power - and output. I'm guessing the output will be logic drive level not power switching.

Probably gives an output when a magnet comes near.

Try +5V ( or maybe 12V ) on the red, ground on the black and put a meter on the blue. The move a magnet near it. That's a guess btw.

Graham

Hi, Larry. It's possibly a Micro Switch/Honeywell 103SR13A-1 Hall-Effect Digital Position Sensor. If it is, it requires a 4.5V to

24V supply, and has an NPN-type current sinking output which can sink up to 20mA from the + end of the power supply when a strong magnet is positioned in front of its face, like this (view in fixed font or M$ Notepad):

| | VCC | VCC + | + | | | .-. | .-----o------. | | | | 103SR | | | | | Sensor | '-' | | | | | | .------o------' | Magnet | | | | | | | | |/ | | | -| | | | |> | | | | | | | | | | '-----o------' | | | === | GND (created by AACircuit v1.28.5 beta 02/06/05

I really think you should get out your calipers and go to the Honeywell site, and look up the part and the specs. The way I read the installation instructions, your wires should be red, black, and green or red, black, and white.

Feel free to post again. I'd be curious as to whether this is the part. "MICRO USA" is a trademark of Micro Switch, though, which now is owned by Honeywell.

Good luck Chris

this is a guess but.. Red = 5..15 Volts, Blue is the common and black is the NPN (open collector) output.

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