Considering a milliohm meter to measure the resistance of windings in a 3-phase motor. Typical resistance is in the range of 0.1 ohm and need to discern probably 0.001 ohm differences in order to determine if there are problems in the windings.
Any recommendations out there on milliohm meters? Are the $400 units okay, or do I need to spend several thousand?
Steve G. in MD
My choice would probably be Cambridge/IET 510A with 1uOhm resolution and 0.02% basic accuracy 
There are some deals on ebay from time to time, but it is pretty rare... I believe that new one cost around 2k USD.
However, for more reasonable budget I would use my DER EE (IET) DE 5000 LCR meter, with 20000 counts on 20 ohm range (parallel/series mode) it has 1 m Ohm resolution, or DC resistance resolution of 10 m Ohms. Nice thing is that it is not expensive and it supports 4 wire measurement.
My choice would probably be Cambridge/IET 510A with 1uOhm resolution and 0.02% basic accuracy
There are some deals on ebay from time to time, but it is pretty rare... I believe that new one cost around 2k USD.
However, for more reasonable budget I would use my DER EE (IET) DE 5000 LCR meter, with 20000 counts on 20 ohm range (parallel/series mode) it has 1 m Ohm resolution, or DC resistance resolution of 10 m Ohms. Nice thing is that it is not expensive and it supports 4 wire measurement.
