How can you tell if an electrical shock is coming from your drill?

Question

I was standing a metal ladder on my enclosed porch, but the electrical outlet is inside the home, not out on the porch. I successfully drilled the first hole in the concrete ceiling with no effect. The second time is when I felt a slight electrical shock, wearing rubber soled shoes, I should add here, that is was raining outside, but I nor the cord were getting wet or standing in any water.. Any other suggestions would be greatly appreciated. Thanks

Answer 1

Before continuing with the drilling please use a GFI (Ground fault interrupter) socket to plug your power tool into.
The conditions you describe can be enough to get a shock from the equipment itself so a precaution to minimize your early death may be prudent.
There is also a potential that your drill bit is coming in contact with a charged line, either one that has a intentional charge such as wiring inside of a electrical conduit, or an unintentional one, such as wiring that "Should" have been inside of a conduit.
A Tifs sniffer (Small pen like device that lights in the pescence of a current, available at most hardware/electric supply stores, can quickly determine if that is the case.....

>>> USE THE GFI<<<< Always.....

Answer 2

Sometimes people feel something that is like a shock, but it is not coming from the outside of the body. It is coming from a nerve inside the body. Think pinched nerve, but much MUCH less pain and lasts only a fraction of a second.

If it really is a shock, it also could have been from static electricity. That is extremely unlikely under your circumstances, but I did want to mention it.

If you are correct, that it was the drill, it is obviously very dangerous. Discontinue using the drill untill you find out for sure.

Is the case of the drill metal or plastic? Is the power cord two prong or three prong? Is the extention cord two or three prong? Is the outlet two or three prong? Do you know for certain that the grounded part of the outlet is really grounded?

If you are comfortable working with potentially dangerous electrical voltages, you can do a test. If you are not 100% comfortable with this, don't try it. Have someone who knows electricity do it.

Set a volt meter on whatever scale it takes to read 120 volts ac. Plug the drill in exactly the same as it was when you had the problem. Do this all inside, perhaps on a table or the floor. Touch one lead of the meter to a known ground. VERY carefully touch the other lead of the meter to a hot wire. Remember that the lead is now hot and is therefore dangerous.

Does the meter read between 110 and 120 volts ac? Remove the hot lead. If the voltage was okay, continue. Keep the grounded lead where it was. Touch the hot lead to any metal on the case of the drill. This includes the chuck; obviously, be carefull since the chuck is moving. Is there a voltage reading. ANY voltage reading is enough.

If there is, stop; you have found that the drill is dangerous. If not, continue. Touch other metal parts of the drill's case. If still no voltage, turn the drill on. With the drill on, redo the testing of the case.

As above, if there is any voltage, no matter how small, there is a problem. To clarify, one or two volts won't hurt you, but the are making a statement. That statement is that the drill is not properly grounded. If it is not, it can cause you harm at some point. The fact that it is not right now isn't important. It is still dangerous.

One last test to really be safe. Put one test lead into the hot part of the electrical socket. As before, remember that the lead is now hot and is dangerous. Put the other lead onto the metal parts of the drill. Now, the meter should read 110 to 120 volts. As above, try it with the drill on if it does not produce the voltage with the drill off.

If it does NOT, it means the drill is not grounded. If the case is metal, that is very dangerous. If it is not metal, it should be okay, even though the chuck is metal.

No matter what the tests show, you should be using ONLY a GFCI outlet when working outdoors OR near water pipes. Actually, you should be doing that any way because you never know what you are going to hit when drilling.

The idea of using rubber gloves or shoes or anything else to protect you is an urban legend. The things that the professionals use are not at all like what you would have. Also, they are trained to use the protective gear and to do what they do with the electricity. This is not something that can be learned here, or even just from a book.

Using an aluminum ladder while doing anything electrical is scary. Personally, I want fiberglass for anything that I do.

Answer 3

It could have been grounding current. I think it is the material you are drilling that is causing the problem. If your drill is safety rated it should protect you from getting electrocuted but maybe work with rubber gloves too, and when it is not raining.

Answer 4

Are you sure it was an electrical shock from an electrical source in your home? It's possible what you felt was physiological (like pinching a nerve) and not related in any way with your electrical system.

Answer 5

Is there any electrical wires in the concrete or above it.??