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Resolver Wiring; Colors & Functions

If you ever plan to replace or test a resolver then you need to know the functions of each wire.  This can be very difficult to determine with out a little knowledge and a voltmeter.  There is an industry standard for resolver wire colors that most manufacturers choose to use.  These colors are as follows; Sometimes Yellow/White can be used in the place of Black/White for Excitation-.  These are industry standard wire colors but you will come across other brands of resolvers with their own proprietary color designations.  When this happens you will need to use a voltmeter to assist you in determining wire color versus function.Almost all resolvers have 6 leads.  Use a voltmeter to ring out the leads and determine which 3 pairs of wire are circuits.  Then record the resistance of each circuit.  The Cos and Sin circuit will have the same resistance, so the circuit with the different resistance will be your excitation circuit.  If any circuits ring open, or all three circuits have different resistances then your resolver could have a damaged winding and need to be replaced/rebuilt.These are some basic tips on how to determine a resolvers wiring.  In order to continue on and designate exact wire functions on nonstandard wire colors you will need to excite the windings with the proper frequency and use an oscilloscope.