How to determine the pin configuration for fractional horsepower compressors and apply the RP041 & RP081.


To determine unknown terminal configuration for a compressor with terminals X, Y, and Z, take a resistance reading between each terminal using the RX1 scale  and write down your readings.

The highest reading will be between Start and Run.  The other terminal has to be Common.

The reading between Common and Start will be the middle value reading.  The reading between Common and Run will be the lowest reading.

An Example:

You read 7.5 ohms between X and Y.  You read 1.5 ohms between X and Z.  The last reading between Y and Z is 6.0 ohms.  This makes X and Y the Start and Run terminals and Z

WARNING:  If you read the same resistance between all three terminals or read any resistance to the body of the compressor at all, the compressor is shorted and should not be hooked up to electricity





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             Last modified: July 20, 2002