Anybody have experience with doing ground testing for msha? We are running into a problem when we measure the circuit ohms. We start out with a 500' spool of wire and have .7 ohms of resistance, and when we measure to the motor housing will will wind up with -.6 ohms. We think it's because we...
I used to do Msha testing so am familiar. Vfd cables have a great ground internally though. We, the installer, are adding all these motor frame jumpers. I was told by fellow workers it’s normal here so Im thinking it’s just habit. Obviously most motors dont come with a way to do this legit so some of it’s wonky.
MSHA/OSHA CFR 77.513 Gripe about Federal inspector. Jump to Latest 3.5K views 19 replies 9 participants last post by Big John acro Discussion starter
Interesting MSHA has no authority over the buildings here is the kicker not in the mine. That was OSHA. Ended up in HR again over that one. Fortunately the mine manager agreed with me and wanted to know why everyone but me was rolling over. After that I was the official driver for the MSHA inspectors. Some of them hated me. I am from Missouri ...
Type G-GC has 3 wires for the hots and multiple smaller ones for the ground and ground check. MSHA requires a ground continuity check each year, usually you stretch out a small wire (#16 or so) from the motor frame to the source and measure resistance. If you have a ground check wire in the cable, simply measure resistance from it to the source, no need for a long single wire.