Electrical Wiring in the Home/wiring a switch


QUESTION: We are working with 220-240 volt 20 amp receptacles.
There is a small switched version of a 120-240 volt 20 amp duplex receptacle where the top half is a switch and the bottom half is a receptacle but I believe the switch is only to control a light and does NOT control the lower receptacle itself ??
First .... could this 120-240 volt switch/receptacle combo be re-wired to make the switch control the power to the receptacle and if yes, would it only work on 120 because I assume the switch would be single pole ?  ... or could it be wired to control 240 volts through the switch to the receptacle
Second ... If you can't run 220-240 thought the switch, is there a different heavy duty version ( but the same physical size ) available that will let you run the receptacle half through the switch half. ? .... a Nema 6-20R on the bottom with a controlling switch on the top half.
I'm trying to keep this switch plug combo contained in a standard knock-out box rather than having to go to a large wall mounted switch.

ANSWER: Robert Wilber
Philadelphia Licensed Electrician
Philadelphia License # 3516 - 16765
Electricity is dangerous!
You can be injured or killed!
Improper installations can cause fire, injury and death!
Are you qualified to do this work?
National Electrical Code definition, NFPA 70 2008 Article 100: Qualified Person. "One who has skills and knowledge related to the construction and operation of the electrical equipment and installations and has received safety training to recognize and avoid the hazards involved."
Electricity is fire in a box! Death on a leash!
Always check with the local “Authority Having Jurisdiction” for an official interpretation before making installation decisions.
In Philadelphia, it is unlawful for anyone except an individual licensed by the City of Philadelphia to install electrical equipment and wiring.
Homeowners are not allowed to install wiring.
The owner of any property wherein any such installation is discovered shall be issued a violation by the Department of Licenses and Inspections.
The limited exceptions include replacing devices and fixtures at existing outlets.
Contact the Department of Licenses and Inspections for more information.
You are more likely to be killed by 120 volts than any other voltage [120 volts creates the PERFECT fatal current through the human body's electrical resistance!]
Ground Fault Circuit Interrupter (GFCI) [downloadable GFI safety pdf]
This information is provided for the use of parties as they see fit!
I am not responsible for the application of this information by any party, including those lacking sufficient skill or knowledge to perform these steps safely and any hazard created is the SOLE responsibility of the user.
I have never seen a NEMA 6-20 receptacle combined with a switch.
I have seen NEMA 5-20 receptacles combined with a switch. These are only to be used to control 120 volt loads or, if rated for 277 volts, a load connected between the phase conductor of a 480/277 volt wye source and the neutral of the wye.

Why not use a two-gang box?

---------- FOLLOW-UP ----------

QUESTION: Thanks for the response ... I just needed to confirm that a Nema 6-20 combo was not available,
I already have a system that is partially working but I wanted to modify it.
I live in Mexico, so code is not an issue ... only safety.
I have a 2 gang 120-240 volt 20 amp receptacle box supplying 240 volts, at one end of a 17 meter long swimming pool. Plugged into this box is a 17 meter long insulated 12-3 power cord which then goes through a single pole switch ( with only one leg of the line going through the switch )
The switch is then connected to another 2 gang 120-240v 20 amp receptacle ..... the 2nd leg of the 240v by-passes the switch and goes directly to the receptacle. Into this receptacle is plugged a 240 volt reversible motor which powers a pool cover mounted on a roller.
The 2nd switch is 2ft from the box and the box is 2 ft from the motor.
All of this line is set back 4 ft from the length of the pool.
The problem is that as we power out the pool cover and pull it slowly by hand ( it's not an automatic one on tracks ) down the length of the pool to the end that has the first power supply box I have to quickly reach out with one hand and try to unplug the power cord to stop the motor from turning and re-winding the cover.
A switch mounted at this point would be an easy fix for the problem.
Convoluted .. right.  But's that the way the house was built... and the house is all brick and stone so I have to live with it.
Being as the type of switch I need is not available would I be able to do the same thing at the supply end as I have done at the pump end.?
Because I have used a single pole switch, with only one leg going through the switch, when the switch is off there is only 56 volts at the receptacle where the pump is plugged in.  This is not enough power to even activate the pump so it doesn't turn on.  When I turn on the switch, 240v is supplied and the pump works fine.
Could I safely do the same thing at the supply receptacle.
Remember .... I know as an electrician you don't like going against code but as explained, there is no code here, so it's only a matter of safety.

National Electrical Code


Article 90
90.1 Purpose.
(A) Practical Safeguarding. The purpose of this Code is the practical safeguarding of persons and property from hazards arising from the use of electricity.


If one abandons standard practices developed and refined over many years in response to safety considerations, then any solution is as good as another.

---------- FOLLOW-UP ----------

QUESTION: You started off sounding like an intelligent person interested in solving electrical problems but your last answer proves you to actually be a moron.
I explained the situation and asked for a " safe " solution.
All you did was quote a code that does not apply to my situation.
Thanks for nothing

What I did was point out that the "unnecessary" and irrelevant code that you reject out of hand is the basic premise on which all safe electrical work is performed. The reason for the quote was to point out that the PURPOSE of the code is to make the use of electricity safe, not necessarily easy or convenient.

If you choose to seek a simpler solution to an electrical condition that is so much more reasonable for your needs than the process followed by the literally millions of obvious idiots working in the electrical trades, including construction, engineering, design and manufacturing and possessing the combined knowledge derived from tens, if not hundreds, of BILLIONS [I am an electrician, not a mathematician. There are roughly 600,000 electricians who clock 2,000 to 3,000 working hours each year and have, in increasing numbers, for the past 100 years!] of hours of exposure to, and contemplation of, the safe and useful application of electrical energy as we understand it, then why would you ask someone who subscribes to those values for a solution ignoring them and then have the audacity to suggest he is lacking in acuity?

The code ALWAYS applies, not because it is a regulation, but because it is the standard of best safe practices. If that doesn't matter, a five year old can come up with a solution that will work.  
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Electrical Wiring in the Home

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Robert Wilber


Licensed Philadelphia electrician serving Delaware, Chester, Montgomery and Philadelphia County in Pennsylvania. I install and repair residential, commercial and industrial wiring and lighting. Troubleshooting and repair of problems that stump other people is my favorite. I am willing to help people figure out why things don`t work. I understand motor controls, transformers and machine wiring. I do not teach basics to novices or do free design work.


Experience in the area I have 44 years experience in residential, commercial and industrial electrical construction and repair, 480 volts and below. This is not to be confused with one week repeated two thousand times.

44 years experience in residential, commercial and industrial electrical construction and repair

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