It is in use and I would like to continue using it. Part of the year I use it for a space heater drawing 20amps and on the 120v outlet I want to use a small air compressor that draws 10amps.
It is going to be super difficult to get a new line from the panel so that is why I am trying to make this work. Reading this article led me to believe this was possible: http://www.emgw.org/papers/ShopWiringProof.pdf
Ok, do I need to just wait for others to respond? First time to use this forum for anwers.
Hello there and welcome to Just Answer. My name is XXXXX XXXXX I will be assisting you today. I am an engineer with over 30 years of electrical and electronic training, repair and installation experience. I will try and answer your question accurately and precisely so that we can get you on your way.
What is the measured voltage across the 240V receptacle? Measure the two hots and also each hot to ground.
Please let me know so that we can continue.
I am not at home to test it again, but when I tested last night it was 240v from one hot to ground and the other was essentially dead (hot to ground). I have a diagram, let me try to attach.
No, I understand.
You can't possibly get 240V from hot to ground so we probably need to have you at the receptacle with your meter so that I can walk you through this.
Ok, in that case I can contact you back in a few hours when in front of the wiring. Also, not sure how to get you the diagram. Each time I try to attach it I get the error below. Let me know if there is another way to send this to you.
You don't have permission to access "http://www.justanswer.com/electrical/7syr5-hello-i-240v-outlet-want-add-120v-outlet-nearby.html" on this server.
You can email the file to email@example.com marked for my attention (Steve555).
But I don't really think I need it. You have two issues here. 1. Is the arrangement within code and 2. Why the odd voltage readings.
Let's get the voltages sorted first and then we can discuss code stuff.
Thank you. I sent the diagram via email just in case you need it. I will contact you again with the voltage readings when I arrive home later today.
Ok, I'll be here. If not, I will be emailed.
Reply only when ready - to keep my waiting list clear..
Ok, I had a chance to test the voltage. each hot to ground was ~120v and hot to hot was ~240. All that seems correct.
Ok. As a rule, what you are doing is not good practice but, (and I'm sure I will be informed if I am wrong here) there is nothing in the code preventing running some 120V receptacles from a 240v circuit providing:
The breaker is sized in accordance with the receptacles ie. a 2 pole 15A or 20A breaker AND you have a dedicated neutral which you indicated that you do.
If your existing circuit has a 30A breaker - that is not ok. You would have to size that breaker down.
I did get the diagram. All looks good. The usually warnings apply about messing with electricity so please be careful.
Good luck and I'll be here if you need help.
What are the two hot to neutral measurements at the 240V outlet?
Yup. So that's not right.
You are going to have to investigate that 240V circuit. Is the receptacle the only outlet on that circuit? Is the neutral dedicated to that circuit or does it tie in with something else?
Unless you have a 30A receptacle, it is a violation of the code (and potentially dangerous) to use a 120V receptacle with anything other than a 15A or 20A breaker. The wire size is important but the issue here is the overcurrent protection. Duplex 120V receptacles are rated for 15A or 20A circuits (look on the outlet for the rating).
Given that a breaker should not be loaded to more than 80% of it's nominal rating, your load is excessive for a 20A breaker.
What you COULD do is get yourself a NEMA 5-30 receptacle (30A 120V) but it has a different pin configuration. It may work for you.
The only way around it is to put in a small 4 or 6 pole sub panel and wire a couple of 120V circuits from that. Sorry :(