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240V wiring issue.

Posted by isitcode (My Page) on
Tue, May 22, 12 at 0:55

Hello,
I have a kitchen that I am remodeling. There is a single 240V stove connector at the bottom of one wall where I had my stove unit, including electrical cooktop, plugged in.
I want to replace that stove with a seperate drop in electrical cooktop range and a seperate in-wall oven, both 240v.
Question: Can I run another cable run from the original 240v outlet and use it to connect my in-wall oven? So that I would use the original for the drop in cook top,and the new one for the wall oven. Or, do they need to be on seperate runs from the circuit breaker box?
thanks,
isitcode


Follow-Up Postings:

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RE: 240V wiring issue.

This is actually one of the few times this is permitted exceptions to the rules. You can tap off your 50A range circuit to feed a separate oven and cooktop provided the split off wiring is rated for 20A or more.


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But you still may...

want to run a second circuit. If the cooktop is one of the bigger induction unit it may draw most of the 50A existing circuit itself. ...


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RE: 240V wiring issue.

What are the power requirements of each device and what do the installation instructions call out?


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RE: 240V wiring issue.

Thanks. I am not sure if the circuit breaker is 50 amp. But I did find out the 240 v cable is aluminum. As for the device stats, I have not bought them yet, all I know for sure is that they will be 240 V.

So, I guess I need to identify the circuit breaker load first. Will it state the info on the breaker? Did not see it on the front, may have to take the panel off to get a better look. The cable has aa 8000 on it. Not sure of the Gage. But it looks like 2 Gage to my untrained eye, kind of big though.
Assuming it is 50 amp, I just replace the current connector with a junction box and run a new cable (20A) to the second (new) junction box 4 ft away correct?
All colors together, I.e. Black to black, red to red, etc...
Thanks again,
Isitcode


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RE: 240V wiring issue.

"...all I know for sure is that they will be 240 V. "

The issue is how much power (and current) the devices need to operate.

Without any knowledge of the power requirements, why would you even consider "run a new cable (20A) to the second (new) junction box 4 ft away"?


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RE: 240V wiring issue.

Note there are special requirements for making connections to aluminum conductors. You can not use regular wire nuts. Further, as brick says absent knowing the requirements and what you have existing, we can't really make a read as to whether tapping the existing cable for both units is going to work or be safe or legal.


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RE: 240V wiring issue.

Why am I considering running from the existing box? Did you really ask that? Because it is easier than running a separate line.
Don't confuse my looking into every "possible" option with side stepping safety.
If it proves unworkable, I will go whatever route is best.
I am in the research stage, and that means talking to people like you guys, friends, and eventually, professionals.

Thanks,
Isitcode


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RE: 240V wiring issue.

Running the wire is not the primary issue. The first thing is to identify the loads to be served. Already pointed out by others. If that concept is not yet grasped, turn this project over to an electrical contractor. If you were building a highway bridge, would your first concern be that it be adequate to support the loads to be imposed?


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RE: 240V wiring issue.

If you have a legitimate 50A circuit *AND* if the installation instructions do not require otherwise AND if the load of the aggregate use doesn't exceed the rating, you can tap IF you use the appropriate connectors and your tap wiring is rated for at least 20A.

However, given you don't have info on the loads NOR do you know what wiring/capacity you currently have we can't even say if you put a regular stove there even.


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RE: 240V wiring issue.

Thanks Ronnatalie,
I understand I need more info, working on it. But for now, my main question about running from existing cable has been answered. Why others insist on all the details when it really is not needed to answer my initial question is beyond me. Your answer is the one I was looking for.
I always intended to bring in an electrician to consult. But I wanted a base of information so I did not sound totally ignorant. As long as the NEC states it is OK with a 50 amp run and I don't exceed my total load I will start with that when the electrician comes round.
BusDriver, try to lighten up, we are not all idiots you know. :)

Thanks again.


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RE: 240V wiring issue.

Why others insist on all the details when it really is not needed to answer my initial question is beyond me.

It's because your post made it fairly obvious that you don't have much experience with wiring. So instead of simply answering your question, they were attempting to teach you the right way of approaching the problem.


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RE: 240V wiring issue.

Teaching is always welcome. Ronnatalie comments were informative without the condescending remarks displayed in say, Bus Drivers remarks.
"Running the wire is not the primary issue. The first thing is to identify the loads to be served. Already pointed out by others. If that concept is not yet grasped, turn this project over to an electrical contractor. If you were building a highway bridge, would your first concern be that it be adequate to support the loads to be imposed?"

No reason for this BS!


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RE: 240V wiring issue.

So it is BS? How did my advice harm you? It is evident that a difference between us is that I know what I am doing and you do not.


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RE: 240V wiring issue.

"Posted by bus_driver (My Page) on Wed, May 23, 12 at 18:55

So it is BS? How did my advice harm you? It is evident that a difference between us is that I know what I am doing and you do not. "

Never said it harmed me, just annoyed me. Your above comments are a prime example of what I was talking about. There is a way to have a discussion, and then there is the guy (you) who lives for the goth-ya. You come off as arrogant, condescending, and frankly, you completely missed my question and went into extraneous info I did not ask for nor need.
You seem to want to show how much you know, but all you do is show your ass.


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RE: 240V wiring issue.

And you come off as so ignorant you should probably not be touching wiring.

Circuit ratings (amps, not just volts) are driven by the load to be supplied and determine conductor sizes.

it is not a guessing game.


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RE: 240V wiring issue.

The primary concern on this forum is electrical wiring. For situations where one's feelings are the emphasis, different forums are more appropriate.


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RE: 240V wiring issue.

"Posted by brickeyee (My Page) on Thu, May 24, 12 at 8:19

And you come off as so ignorant you should probably not be touching wiring.
Circuit ratings (amps, not just volts) are driven by the load to be supplied and determine conductor sizes.

it is not a guessing game."

What? Who is guessing? I asked a simple question concerning code regulations. Can I run two 240V connections off of one to hook up two appliances. That's it, that's all I wanted to know. Is it allowed IAW the NEC to do it?
I did not want lectures about load, amps, power, watts, or any of the other details I will handle once I get an answer to that one simple question.
Ignorant? I have a degree in Electrical Engineering from Kent State and a computer Science degree from HPU. I worked as a Communications technician for 25 yrs in the Marine Corps.
I sir am far from ignorant. But I do know when someone is trying to be an ass. I don't have a copy of the NEC in front of me, nor have I worked in the electrical field since getting my degree in 1984. Much has changed I am sure.
So, I suggest you go back, read my initial question, figure out words have meaning, and then tell me who the ignorant one is in this post.
Only one person has answered my question completely, he is the only one I would say actually understands my question, the rest of you seem to want to figure out all the details of my remodel before I do, or before I need it.


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RE: 240V wiring issue.

But the answer to your "simple question" is sometimes yes and sometimes no.
Everyone was trying to get you to supply the information to determine whether in your particular situation, the answer was yes or no.
The problem with just answering a question without knowing all of the details is that many people will take a partial answer and run with it and create an unsafe condition. You may not be one of those people but we have no way of knowing that.


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RE: 240V wiring issue.

Greg, they don't need to know what I know or don't know, they only need to try to answer my simple question, for which I am very greatful. But telling me I am ignorant because I did not know the power requirements for devices I have yet to buy is just, well, ignorant. I only asked one, simple question, can I run two devices off one 240V line? That's it. The answer is yes, iaw the NEC, as long as it is a 50 A breaker and your total does not exceed the load limit.
The details I will leave to an electrician when I ask him/her out to give me an appraisal while he/she verifies I am in fact running off of an existing 50A breaker.
Savvy?
Thanks again,
IsItCode


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RE: 240V wiring issue.

I understand. I'm just trying to point out where the misunderstanding originated. It has now degenerated into name calling on both sides, but I'm trying to ignore that.

You never said that you were going to use an electrician until after you started getting what you considered rude replies.

From the information we received, it sounded like you were going to tackle this project yourself. We were trying to stress that the answer to your simple question is irrelevant until you had all of the information.

But since you are using an electrician, you don't even technically need the answer to your simple question. Just tell him what your end goal is and he'll accomplish it in the best way possible. Whether that means running a new line or reusing the old one.


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RE: 240V wiring issue.

"they only need to try to answer my simple question"

For the information provided the answer is NO.

If you understood what you are trying to do you would likely have thought it was no from the very start.

There are some very special circumstance that MIGHT allow what you asked to be done.

Since you do not have and do not wish to provide the required information, the answer remains NO.

Ronnatalie hinted at the possible conditions that might allow the extension, but not all.

An iomrtant ones that dxoes not appear mentioned is the number of conductors in the branch circuit.

3-wire 240 V stove connections have previously been allowed under an exception, and remain code compliant if NOT ALTERED.

If you alter the branch circuit (and depending on the AHJ they can legitimately call simply moving the receptacle box for a different stove 'altering') you are required to upgrade the 3-wire (hot-hot-neutral) circuit to a 4-wire (hot-hot-neutral-ground) circuit.

And no, just adding another wire is generally not allowed.
A new cable is needed.


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RE: 240V wiring issue.

Isitcode,

some of these folks are real electricians who are giving you free advice. If you look up their old posts you will see that bus_driver and the others have given tons of free advice to people for years.

I call myself an "amateur" electrician and hobbyist because I never took the exam. I read through all the code books for fun myself. I know enough to know things are dangerous and to get help when I am not sure rather than guessing. They are asking legitimate questions to fully explore your problem not to make you look bad.

Electricity can be dangerous and safety trumps egos in that area. Electricity is not a court of law where they demand only a "yes" or "no" easy answer.

There are rules, but each house has some creative way you have to apply the rules that are (a) SAFE (b) code compliant (c) will make your local Inspector happy. Old houses are even more hard to predict without pictures and an onsite visit.

Aluminum wire has special safety issues. It is hard for forum people who have never stepped into your kitchen to see all the different issues with a single question. I have had friends ask me if such and such is possible. I usually say yes, but I need to see your house. And sure enough 50% of the time there were critical things they never told me because they didn't know it was important.


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RE: 240V wiring issue.

"never told me because they didn't know it was important. "

This is the reason electricians, plumbers, and engineers, (and others) often give 'complicated' answers.


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RE: 240V wiring issue.

isitcode, let me just explain a few things.
Your attitude is a very common one.
- You come here highly educated, but not in anything that is related to the topic at hand, although I am sure you would disagree, but this IS true. Your engineering and computer degrees have NO relation to construction electric and codes.
- You are looking for a specific answer that YOU think can be easily conveyed.
- You either don't get that answer right away, or someone is looking for more info to give a more accurate answer, or someone is vague due to the inadequacy of your questions(s).
- You then get annoyed and feel you are being lectured when someone tries to give you the safest answer given the level of the question.

Let me tell you, we see this A LOT. Most folks want an "XYZ" answer with no trouble. Well, let me tell you, that is a rare case. Most times more information is needed to give the safest and most accurate answer.

I know you'll probably get even more annoyed at my explanation/reply here, but I really don't care. :)


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RE: 240V wiring issue.

Thank you. After more research on the ranges and wall ovens, I have decided to err on the max loads in the industry for these appliances. I have decide on a separate 40A 8 / 3 drop for the wall oven appliance. I have not seen one that would exceed that amperage.
The existing 50 A circuit will be used for the cooktop range. My circuit breaker panel is full but if I install double breakers in two single slots and move two of the 20 A amp circuits to them I can free up room for the new 40A 240V breaker.
I bought special connectors for the aluminum cable so I can connect it to copper without the two making contact. Bought the goop for the aluminum as well.
I have removed all the drywall, drilled all the holes, and am ready to run the wire. I have decided to do all the work myself.
Thanks again for your help, if nothing else, your comments made me think.
Btw, petey, I really don't care either..., I have thick skin.


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