November 26, 200817 yr I have a Central Machinery table top drill press and the switch died a few days back. I decided I could use a house hold type light switch to replace it. What i have rigged now turns the motor on when i plug it in, but I when i turn off the switch I also turn off the breaker! I'm not too electrically inclined, will this type switch work? Any suggestions would be greatly appreciated. Russell
November 26, 200817 yr Does the original switch look like this??G8989 Toggle Safety Switch if it's the drill press I am thinking of, that should be a near direct replacement. might want to double check the mounting hole size. P.S. breaker shouldn't be tripping when you turn it off, as that means there is a short somewhere I would think. -Aaron @ the SCF
November 26, 200817 yr Author Thanks Aaron, but it's not. It's some goofy looking arrangement with a separate on and off button. I agree about the short. I need to replace the terminal block because it disintegrates a little more every time i mess with it. I just wanted to be sure about the type of switch more than anything. Russell
November 26, 200817 yr Can you post a pic of your setup. There is no reason a SPST household switch can't work, unless you have a SPDT and have it wired wrong.
November 26, 200817 yr not having seen it, and what you did wrong, I am probably talking out my (T)... It sounds like the OFF position you mentioned is putting your power directly at the ground, Get help if you are not sure, electricity can kill. 30 micro amps causes unconsciousness, 50 micro amps death. Our skin protects us from most of the charge when we get a shock, but the science says it doesn't take much to kill us . Please work safely a message from your Loving Union Electrician IBEW 305 JIW
November 26, 200817 yr You have not installed a switch, you have installed a breaker buster. The 2 hots, black, are on the same screw, hot wire it on all the time. When you turn the switch on, you are sending the hot, black, to the nuetral, white, and shorting the line which blows the breaker. Remove it and start over. You should be using a DPDT, Double pole, Double throw switch. If you insist on using the switch you have, wire nut the two whites together, and place the black on the input side on one screw, and black on the drill side to the other screw. This is not a 220 volt machine, correct?
November 26, 200817 yr It looks to me right now that you have both of the black wires twisted together under one screw, and both of the white wires twisted together under the other screw. What's happening is this: with the switch off, it is acting like a terminal strip running straight from your cord to the motor. With the switch on, it is shorting straight from the supply (black) to the return (white) and popping the breaker. In all cases the power to your motor is live. Only switch ONE color of wire. Black. Both of your white wires should be twisted together and held with a wire nut twisted on far enough so you only see insulation. Tape it too if it makes you feel better. The white wires should not get connected to the switch at all. One end of each black wire should end up under each screw. The black wires should not touch--the switch will make them touch inside. The switch basically "breaks" the black wire to stop the current. You can leave both the green wires twisted together under the green screw.
November 26, 200817 yr Author Thanks a lot guys, worked like a charm. I still need to change out the terminal block and get things covered up on the motor and it should be good. Russell
November 27, 200817 yr Russell, Just so you know gold color screw means black (line) wire should be connected to it. Which is what you see with the switch. The white wire is a neutral which completes to circuit. If you look on wall plug you see silver colored screws on one side and gold colored on the other. Which means the white (neutral) wire goes there. The same thing applies to electrical extension cords if you change the cord end look for gold and silver screws, and wire accordingly. Thats why these days we have a wider blade on male plug. So neutral wire is to neutral, and line wire is to line. The green wire is a ground wire which just connects all the electrical equipment together. That way you don't become the ground, and shocked. Edited November 27, 200817 yr by LarryM
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