Changing single phase to 3 phase

[Frank DuVal]

Me too. Irrigation wells around here typically have 480 volt control circuit and this is not a common occurrence. I have seen it happen more frequently, even at lower voltages, when indoor equipment was being used outdoors.

"Not a common", so that means you have seen it happen then?.

NEMA 1 might be the real issue back then. Remember, rural sawmills were open sides with roofs. So when the fog rolls in here in the east, everything is dripping wet.

 

[kwired]

"Not a common", so that means you have seen it happen then?.

NEMA 1 might be the real issue back then. Remember, rural sawmills were open sides with roofs. So when the fog rolls in here in the east, everything is dripping wet.

Clean and dry - and and NEMA operators/contact blocks maybe haven't seen it. But many the places I work are never that clean and dry that there isn't some chance of flashover via environmental contamination, especially when using 250+ volts to ground. Proper rated enclosure buys time, but even after enough time has gone by some of that environment finds a way in.