Wiring 120volt and 240volt Electrical Outlets

Discussions about Wiring Electrical Outlets

Upgrading Outlet Electrical Wiring

William, from Winnipeg, MB, Canada asks: Hi I'm doing electrical in home which is over 100 years old. I was wondering if I can use the current 2-wire cable that is connected to two-prong outlets to supply power to new grounded outlets.

Dave's Reply: William, No - you should not use the existing 2-wire cable to connect to grounded outlets, unless there is an external or separate ground wire that is available at the outlet box. it is best to replace the old 2-wire un-grounded cable with new 3-wire cable which has the ground wire. The new electrical cable should be installed starting at the electrical panel where the ground wire may be bonded to the main ground terminal or system.

Outdoor Outlet

Alan asks: I'm installing an outdoor outlet. It's one that has a pole stuck into the ground. The question I'm getting is how deep into the ground does the pole have to be to meet code. The last person did a really bad job and this needs to be completely redone. I just want to make sure it's right this time.

Dave's Reply: Alan, this will depend on the type of support that will be used. For example a pressure treated post may be fine if it is 18 inches deep in soil, or 12 inches deep in a concrete footing. The support material and the environment should be considered.

Wiring Mess - Switching Outlets

Dan asks: I live in an apt complex; the guys that fix things do not really know what they are doing, so I usually just do my own repairs. There is a light switch that operates all four plugs on two different outlets. How can I make the switch only control one plug or even just one outlet. Thank you.

Dave's Reply: Dan, it will depend on where the power source is located, the power source being both the hot and the neutral. If the power source is at the outlets then the outlets can be rewired so they are hot all the time, but if the power source is at the wall switch then the conversion may not be possible without installing additional cable. It just all depends on how the outlets and switch wiring have been installed.

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Questions about Electrical Outlets

Question from Frank in Findlay, Ohio:
Why Do I Have a Low Voltage Reading on an Electric Wall Outlet?

• On my bedroom circuit if I plug in a vacuum that’s 12amps it causes a brown out in the room. The breaker itself is 15 amp. This circuit is also effecting my fridge circuit and caused the fridge to essentially brown out as well, but it’s on its own circuit. Also the electric stove and water heater as well as the garbage disposal will not work either. If you flip on the garbage disposal it will actually brown out the bedroom light circuit. It does not effect any other circuit in the place just that one. I metered all the plugs and got 120VAC. I also metered the incoming power into the box and both hot leads are 120VAC. If I plug the vacuum into the outlet and turn it on I get a reading of 59VAC from the plug in the room and the one associated with the fridge. I switched out breakers and still does it. I’m trying to figure out what would cause this.

Dave’s Answer:
The cause of a Low Voltage Reading on a Electric Outlet Circuit

• A low voltage reading as well as other circuits and devices not working properly in the home is typically caused by a lost connection of one of the main power components within the electrical system of the home. This is typically due to a deteriorating electrical connection or component fault which has failed and is causing a low voltage feed back condition. This is a potentially serious condition that could cause damage, therefore the problem should be identified and repaired by a Qualified Electrician or Electrical Contractor as soon as possible.