Quote Originally Posted by synchro View Post
I think compressor motor currents can vary a lot depending on the temperatures, amount of refrigerant, etc. (which I'm sure StarCat can expound about much better than I can). So I think the expectation would be that the worst case running current is going to be higher than that made on one measurement. Hence the concern for adequate margin. But it's good to hear if things are becoming more tightly controlled with newer equipment.
Back in the 90s when Copeland and Carlyle starting putting the first scroll compressors in residential condensing units, there would, without fail be home owners freaking out about dimming lights on start up in the Brutal Texas Heat. It was not uncommon to see instantaneous inrush of 235A on a 5 ton unit on start. Hard Start gear on single phase systems will moderate this a fair degree. I may not have noted all details on the system but someone making a reference to incorrect sequence of operation is correct, and this needs to be verified. The reference to condenser fan motors is correct, and also the capacitors on those motors can cause problems.
Compressors generally only approach RLA when under what can be considered full to heavy load with condenser entering air temperature at 90F or over.
I have seen brand new gear with wiring errors or defects. I remember a mentor saying to me when I was quite young, " Don't assume that its right."
What I have found to be the case on a lot of newer gear is its designed right on the edge, and the quality of components is not what it once was. Much of it is truthfully not worth having.