[oldred]

The discussion on the 220 volt circuit for compressors reminded me of something I have been meaning to mention but I did not want to high-jack that thread.

Sometimes we use adapters of some sort for electrical devices and often these include a grounding wire that is supposed to be attached to a proper ground but often this is overlooked, an example is those three prong to two prong adapters for older "non-polarized" outlets that have no third hole for the ground prong on plugs equipped with one. Honestly how many of us have actually grounded that wire? OK, what this is about is that grounding for safety is very important and should not be taken lightly, look that ground over and make SURE it is done right because if you make a mistake it could be serious!

Here's what happened, I set up my new 3 phase 220 volt lathe on a concrete floor and proceeded to wire it to a 220 volt single phase outlet using a static phase converter. I just looked at the sketchy wiring diagram that came with it and it looked simple enough, basically just attach the three wires from the single phase line to the appropriate terminals where the ground wire position was clearly marked then attach the three phase side to the terminals as marked, simple right? What I failed to do was to stand back and visualize this set-up and determine exactly what I done and I just ASSUMED that since I followed the instructions then everything was ok, assuming without verifying can get you hurt! A few months later I was running this machine and a thunderstorm was coming up, no problem I though since I was inside in the dry, the lathe was humming along, I had my radio going and all was well in the world. I vaguely remember a bright blue flash and when I regained my senses I had a terrible ringing in my ears, a distinct taste of Copper in my mouth and both my arms was aching almost unbearably. I noticed there was actually even some smoke in the air in the shop as I sat on the floor trying to figure out what happened, this became obvious once I got up and started looking for the problem. There is a power pole with a transformer right beside the shop and lighting had either flashed very close by or even possibly struck the pole or line but whatever the cause there was a huge power surge that came through and apparently I was the source of grounding between the lathe and the concrete floor!

I had just ASSUMED when I connected the ground wire from the single phase outlet I was grounding the lathe but just by looking at this connection it was very apparent that it in no way made a grounding connection to the lathe itself and any grounding stopped at the converter box, this was very obvious but I failed to look for it because I ASSUMED I was grounding the set-up because I was attaching the ground wire according to the instructions, this was correct for the converter but did nothing to ground the machine and I should have seen that.

The moral to this long story is to NEVER ASSUME ANYTHING! Look over all connections and try to visualize the circuit and make sure the device is properly grounded because while at first it may seem to be there could be a problem and you can't afford to make a mistake here, I did and it hurt!

[JohnnyK81]

Glad you're ok!... Because I'm going to need you for rack and pinion trouble shooting down the road.

[matt167]

Another suggestion is, when rewiring, don't cut live wires. it becomes a 'shocking' experience. At least then the breaker clicks tho.. My dad stuck a screwdriver in the furnace blower when I was young to work on it, and my mom had clicked the wrong breaker.... he's still around but it blew him into the wall behind the furnace.. But I'v carelessly done it with lamp cords and when the wire cutters are blown in 1/2 in your hand, it makes you think

[oldred]

A trick I leaned long ago when checking anything electrical was to use the back of my hand to touch the part first before actually grabbing a wire or anything else that might be "hot". If you do this then it will tend to make you jerk your hand away from the circuit as an automatic reflex as the muscles contract from the current if the wire happens to be live, if you touch it with your open hand the muscle contraction could cause you to grab it and it not be able to let go!


Now before anyone comes down on me for what I just said I am NOT in any way suggesting that is an acceptable way of checking for power nor is it in any way a substitute for making sure the power is off before touching anything that might be "live". I am just saying it is added insurance that takes less than a second to do after making sure the power is off, it costs nothing and takes only a second so why not?

[OLNOLAN]

OldRed, Man you're gonna get yourself killed with the rigging you've got going on at your place. Just recently you were looking to splice romex underground. Now you're getting the ever loving hell shocked out of you from the phase converter wiring you installed and improperly grounded and bonded. No offense Man, but why don't you trade out some compressor work or a couple cases of beer to an electrician buddy to come out to your place and evaluate your shop/house wiring to make sure its all safe and properly grounded and bonded. I don't want to read about a good ol boy like yourself getting killed just because you're too stubborn or too tight to do it properly. When it comes to electrical work there is a big difference between knowing just enough to "make it work" and knowing how to make it work and make it safe in regards to fire and shock prevention. Licensed electricians are generally well versed in electrical code. The NEC and the required training are there to prevent things from happening EXACTLY as you described. If this post pisses you off because I'm criticizing your jackleg habits, I'm sorry, but I'd rather piss you off than see you or someone in your family get killed or maimed. Please. Nolan

[oldred]

Originally Posted by OLNOLAN

OldRed, Man you're gonna get yourself killed with the rigging you've got going on at your place. Just recently you were looking to splice romex underground. Now you're getting the ever loving hell shocked out of you from the phase converter wiring you installed and improperly grounded and bonded. No offense Man, but why don't you trade out some compressor work or a couple cases of beer to an electrician buddy to come out to your place and evaluate your shop/house wiring to make sure its all safe and properly grounded and bonded. I don't want to read about a good ol boy like yourself getting killed just because you're too stubborn or too tight to do it properly. When it comes to electrical work there is a big difference between knowing just enough to "make it work" and knowing how to make it work and make it safe in regards to fire and shock prevention. Licensed electricians are generally well versed in electrical code. The NEC and the required training are there to prevent things from happening EXACTLY as you described. If this post pisses you off because I'm criticizing your jackleg habits, I'm sorry, but I'd rather piss you off than see you or someone in your family get killed or maimed. Please. Nolan

I guess I am in no position to disagree with you and I deserved everything that happened to me on that lathe but honestly my electrical abilities are not as bad as it sounds, I knew how to do it properly and knew very well what I had done wrong-after the fact! It was a case of being careless and there simply was no excuse for it. I was well aware of how this looks before I posted it but if someone does something that danged dumb he should tell it on himself but honestly I normally do things right and take no chances on wiring. I have been safely wiring various equipment for the better part of 40 years and that was the first time anything like that has happened and also was the first time I had failed to thoroughly check everything after making the connections, it was so simple I got careless but I will say this myself "IT ONLY TAKES ONCE"!.


You would not have hurt my feelings at all if you had of called that a stupid thing to do because that is exactly what it was and the point I was making was that sometimes we think something is simple when it is not. As far as burying the power line I used approved burial cable and the connectors that are also approved, the panel in this building is properly grounded and the original buried wire that was leaking underground was not my doing. Actually I do know how to do this but looking back at the lathe incident it sure does not look like it!