I know many of you on this forum have a strong background in electrical power and wiring so I hope someone can help me troubleshoot this situation before I loose any more equipment. I built my workshop about 8 years ago. The power company put in completely new 200 amp service for the shop, separate from our house and on a new account. I have quite a few power tools and machines, both 120v and 240v. Ground is via an 8Â’ copper coated steel rod just outside the workshop. A couple of years ago I also put in a 240v surge protector which is mounted next to the load center so I can always see the green lights are on. The protector has 2 wires, one connects to each side. Until yesterday I had zero electrical problems in the shop. Then in the morning I used my 120v Mirka palm sander which is powered from an electronic control box. It ran fine but then I shut it off and 1/2 hour later tried to use it again it ran for about one second and that was it, dead. Power to the box but no output. Seemed very odd to me but I thought it had gotten old and just failed from old age. In the afternoon I was running my lathe and using my 5hp Super Gorilla dust collector, 240v single phase. and it ran fine. Shut it off for awhile and turned it on again but there was only a click in the magnetic starter switch box and the big Gorilla was dead. Climbed up with my multimeter and took the lid off the wire box. Zero volts between the white and black wires after I pressed the start button. I did find 123v between white and ground, zero between black and ground. Then I took the cover off the magnetic starter switch and smelled something burnt. The black wire from coming in from the 240v outlet had gotten very hot where it connects to the switch and in fact started to melt the plastic side of the switch. I checked the voltage at rhe outlet and it is 246v. The surge protectors at the load center and in various outlets show the green light glowing so I assume my ground is ok. Called Gorilla reach support and he agrees that something caused the black side of the switch to short out.
So I have to assume something is wrong with my power, it would be too big a coincidence for both units to fail on the same day if there werenÂ’t a problem. But where do I go from here? I did see the power company putting in new poles and wires over the past few days.