Electrical Dilemna

[Thorold]

Anyway he brushed by the drill press and got a bit of a zap. A little while later he actually touched it and got a good lift.

Yah i know that barefoot may not have been the wisest thing ( especially after the first jolt ) and i know that the press and all electrical is good and my electrical/electronic background had me testing everything and checking all of the wiring only to find nothing abnormal.

To give you some background it's a 14x 30 just 20' back from the house wired underground to a 60a panel.

So the question - there is no ground rod in the installation though it will be in the next few weeks.

Am i in a ground loop situation ?

 

[MrMark]

sounds like you have a hot to metal body of the drill press, nothing else. Don't get off on wild tangents like ground rods, etc.

 

[mrb]

two issues exist. 1st, something is contacting the metal case of the drill press causing it to be energized. 2nd, there is no return path for fault current. The case of the drill press is not bonded (grounded). This could either be at the drill press itself, or further upstream.

 

[Speedy Petey]

Am i in a ground loop situation ?

What exactly are you calling a "ground loop"?

Either way, not, it is not a ground loop. This is not an issue in AC building wiring.

 

[Gary S]

Put a volt meter across the drill chassis and the floor. If it measures voltage there, unplug the drill and measure from common and ground in the receptacle to the floor.

Any voltage at the common or ground in the receptacle says a big wiring fault.

If no voltage at the common or ground pins of the receptacle, but you have voltage at the drill frame, it is time to junk the drill and get a new one.

This is all assuming that Canada has similar AC power as the US.

 

[nehog]

Also make sure all your outlets are GFCI protected, either with GFCI breakers, or GFCI outlets. Not doing so can create hazards that you really don't want in the building.

The base problem is that there is probably excessive leakage in the drill press. Improving the ground may work at bringing that voltage closer to ground potential (never get it exactly to ground, but that's life.) However, this could result in excessive currents flowing along paths that are not intended to do this (the ground path, for example) and even could under some circumstances lead to issues such as current draw even when the device is turned off, and I suppose in a worse case scenario a fire hazard.

So:

1. Install GFCIs on all the outlets.
2. Fix the drill press leakage problem (may need a new motor, but only proper diagnostics will tell you that.)

 

[rburke65]

When you say......." and i know that the press and all electrical is good".....but it sounds....feels....like something is wrong.

 

[larry_g]

i know that the press and all electrical is good and my electrical/electronic background had me testing everything and checking all of the wiring only to find nothing abnormal.

?

I'll bet your son would argue the point that nothing is abnormal... Without knowing what test you performed its hard to guess what may be the problem. However you should be able to measure a voltage bridging the points he touched, the floor and DP. Lay a plate of steel or copper on a wet floor and then measure voltage from the plate to the DP. If you can get the voltage measurement then you KNOW there is a problem that you can measure. From there you systematically start tracing the voltage source down. Do not discount that the floor could be hot and that the DP only provided a ground path. Remote that the floor is hot but it can happen.

lg
no neat sig line

 

[truckn_r]

Drill press has a leak to ground as everyone says, but bigger problem is that somewhere between the drill and the panel, there is a break in the ground wire. If grounding was continuous, the grounding conductor would provide a path of least resistance and you would not provide a path. If the tool has enough of a short, it would trip the breaker. GFIs are the way to go, because if that were a hand held tool, there is a possibility that if you grab it you will not be able to let go.

 

[Stuart in MN]

What kind of plug is on the power cord - two prong with no ground, or grounded? If it's an ungrounded cord, flip it 180 degrees and plug it back in.

 

[Alchymist]

What kind of plug is on the power cord - two prong with no ground, or grounded? If it's an ungrounded cord, flip it 180 degrees and plug it back in.

Better yet replace it with a 3 wire cord & plug.