No fault circuits?

Danbo

Danbo

Joined
Nov 28, 1999
Messages
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My new Beaumont Horizontal Edge grinder blows the no fault circuit in my new shop as soon as I turn it on. Sometimes it stays running for a second or two, and then blows the circuit; but mostly it won't even turn on without tripping the circuit.

Anybody have a clue what to do? I'm having the same problem plugging in my fridge, too. Trips the no fault circuit immediately.
 
You need to measure for any continuity between neutral (the large prong) and ground (the round prong) on the KMG. There shouldn't be any. If there is, you have a ground fault. Same thing for hot and ground (this would be a dead short). But there will be continuity between hot and neutral - that is supposed to be like that.

Also, you can move it to a circuit without a GFI and, with it running, see if you can measure any voltage between the grinder and something that is known to be grounded. Should be zero.

If it passes these tests, it sounds like you need a new GFI. They do wear out as they age. And they don't like large inrush currents.
 
Also, it is not uncommon to have a bad GFI. I have changed quite a few over the years and solved most of the problems. For a piece of heavy equipment in a dry shop, I would remove the GFI and install a regular breaker. Also, make sure the circuit is large enough for the load of the grinder. The breaker should be about 25% larger than the load draw.
 
Danbo,

Here is a section of the owners manual for the K&B Drive, if this is the ones Rob is still selling.

5.1 AC LINE INPUT CONNECTION – Wire
the AC line input to Terminal Block TB1.
GFCI Operation – Do not connect
this drive to an AC power source
controlled by a Ground Fault Circuit
Interrupter. Special software is available
for GFCI operation – contact
our Sales Department.

Here is a link to the owners manual. Look on page 13.

http://state-electric.com/files/manuals/kb/9520.pdf

Take care

Charles
 
You may need a time delay fuse or breaker for the circuit your grinder is running on. Many motors require extra power on start-up that creates a surge causing the circuit to blow.
 
Yes...VFDs have troubles with GFCI circuits.

From what I understand...they are required on new built homes where water might be present...including kitchens, bathrooms,..., and garages.

I've never owned a new home...and do not have any experience with these devices...nor am I qualified to consult on the topic.....but will be glad to share some of the routes taken by other customers.

Some customers that had a GFCI outlet..simply removed the GFCI receptical and replaced it with a standard receptical.

GFCI Receptical:
8602029-11.jpg






Standard Receptical:
6057070-11.jpg


There are a handful of YouTubes on how to replace a receptical:

http://www.youtube.com/watch?v=DuevakEtGvM&feature=related





Other customers have used an extension cord from a standard outlet.

The special software from KB has proven to be unreliable and doesn't work in most cases.

You can also run the machine on 220V. The controller has a single "jumper" wire that you move from the 115V lug...to the 220V lug.


Keep us posted.

-Rob
 
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