Thanks, all for the suggestions. I like the double-insulated scope thought, and that was my next plan as well. Right now, we are doing the obvious. Isolation transformer to the 120V power supply and moving sesors away from lighting. Some are as close as 1-2 inches from the ballast.
We have changed out incandescent lamps with two-lamp T-8 with electronic ballasts in several buildings. Now the fire alarm system keeps sounding false messages. We get nearly all messages. The fire system sensors are connected via a twisted pair and are directly addressable ("smart...
busbar - I agree that it doesn't sound right. That is my perplexing concern. The installation is one motor in a chiller. Since this is an open delta connection, I don't need to apply the two-wattmeter measurement method with my Fluke 39 meter, but can measure the current through each coil...
I have a 1500 ton water chiller at 480 VAC. It is an open transition wye start, delta run motor. Each of the three phases is replicated to produce six phases which are connected across the motor coils in such a way that each coil (in the run state) will have a set of conductors that brings the...
