Pottery wheel machine bonding

[starsandstripes]

I've been doing some work on some 120v pottery wheel machines at a high school. They are plug and cord connected, with 1/6 hp motors. The motors are grounded, but are seperated from the tubular frame by rubber isolators. The machines sit on a concrete floor covered with vinyl tile. These are operated under wet conditions and are gfci protected. There have been no shock incidents as of yet. I'm reading 18v from hot to the frame. The manufacturer did not bond the frame to the motor, but I think it would be a good idea. What do you guys think?

 

[cadpoint]

...
These are operated under wet conditions and are gfci protected. There have been no shock incidents as of yet. I'm reading 18v from hot to the frame. The manufacturer did not bond the frame to the motor, but I think it would be a good idea. What do you guys think?

I thought the best potters wheel was always foot spun ?

Theres no Bond in the circuit to the Motor chasie ?

Did you put all the other equipment to the this same test ?

As one member likes to state did you qualify the ground as a source that is a true ground?

Did you QA the other circuits and other equipment ?

Thats what I think...

 

[bphgravity]

If it is a manufactured product, leave it alone. If you are that worried about it, contact the manufacturer and see what they suggest. They will likely tell you to leave it alone as well.

 

[tom baker]

What kind of meter is giving you 18 volts? If digital, try the test with an analog meter. You may be reading a ghost voltage.