240/120

Signed-In Members Don't See This Ad
Jgrden

Jgrden

Member
Joined
Mar 27, 2009
Messages
6,287
Location
hOUSTON, Texas
Someone has been very helpful to me about wiring in our convection oven. It needs a 240.120 V source. I am confused. We have a breaker that is split into two 110v 50 amp breakers with a cap that makes both breakers activate at the same time. When I wired the oven into the existing 220V wiring I found a black red and white and ground wire. What confused me is the SIZE or GAUGE of the wire. It looked like 12 ga. wire and to me seemed small compared to the 6 or 8 ga. wire coming from the panel. The oven operates on one 110v breaker but is very slow and takes forever to heat up to 204 degrees to say nothing about the 400+ it needs to bake. I am ready to go out and throw the other breaker to see what happens. The wires are proper, twisted with big heave blue caps on them, inside a metal 4 or 5 inch box.
Should I throw the other breaker??
 
Signed-In Members Don't See This Ad
John,
Do not hook the stove to the existing wiring. On a 220v breaker, each breaker is a source for 110v. If you have hooked up your oven to the existing wiring, you may send 220v to the oven, and, no pun intended, fry it.

You need to rewire the breaker/outlet, or actually, get an electrician to do it for you. On a 220v, the back will be one source for 110v, the red (or white) will be another source for 110v, and the ground will go to ground. If you hook up your wiring 'normally', you are putting black to black, white to white, and ground to ground, thusly putting 220v to your oven.

On a 110v circuit, only one wire is to the breaker, and ground to ground. The other wire is "neutral."

But I'm no electrician, so maybe one of our electrician members can explain it better.
 
Padre said:
John,
Do not hook the stove to the existing wiring. On a 220v breaker, each breaker is a source for 110v. If you have hooked up your oven to the existing wiring, you may send 220v to the oven, and, no pun intended, fry it.

You need to rewire the breaker/outlet, or actually, get an electrician to do it for you. On a 220v, the back will be one source for 110v, the red (or white) will be another source for 110v, and the ground will go to ground. If you hook up your wiring 'normally', you are putting black to black, white to white, and ground to ground, thusly putting 220v to your oven.

On a 110v circuit, only one wire is to the breaker, and ground to ground. The other wire is "neutral."

But I'm no electrician, so maybe one of our electrician members can explain it better.
Click to expand...
Padre:
The oven instructions say the source should be 240/120. It came with black, red, white and ground. Does this change what you are saying?
 
John,
You need to read the oven manual and see what it is wired for. If it is a true dual system, then you will be able to wire the oven side for either 220v/110 (240/120).
 
Padre said:
John,
You need to read the oven manual and see what it is wired for. If it is a true dual system, then you will be able to wire the oven side for either 220v/110 (240/120).
Click to expand...
You are right. That is what I'll do. I saved it into bookmarks. Just needed your guidance on which way to go.
Thank you buddy,
John
 
Hmmm

Jgrden said:
Padre said:
John,
You need to read the oven manual and see what it is wired for. If it is a true dual system, then you will be able to wire the oven side for either 220v/110 (240/120).
Click to expand...
You are right. That is what I'll do. I saved it into bookmarks. Just needed your guidance on which way to go.
Thank you buddy,
John
Click to expand...
If the leads coming out of the oven are Red, White, Black and ground it implys 220(240) as does the slow heating when using 110.
 
typically the saying 120/240 means that the current is 120 volts phase (hot leg) to ground......... 240 phase to phase. electric coming straight from the transformer before loss due to wire, connections, and load is usually around 124, 124, and 243 typically. I can not stress enough that you use a qualified and licensed electricain to do these connections for you. one simple mistake and you will be without a home or your life. just a linemans point of view. remember it only takes one milliamp to end your life.
 
Smitty37 said:
Jgrden said:
Padre said:
John,
You need to read the oven manual and see what it is wired for. If it is a true dual system, then you will be able to wire the oven side for either 220v/110 (240/120).
Click to expand...
You are right. That is what I'll do. I saved it into bookmarks. Just needed your guidance on which way to go.
Thank you buddy,
John
Click to expand...
If the leads coming out of the oven are Red, White, Black and ground it implys 220(240) as does the slow heating when using 110.
Click to expand...
AHA !!! I think we are safe and on the right track. The only smidgen of a question was the size of the wire (gauge). It looked to be 12 or 10 gauge. Oh well. I have a pace maker so I will just flip the switch, stand back and see what happens. No touchy the wire while breaker is on. Wires coming out of the oven were four: black, red, white and green/copper.
 
Another one of these I don't know what I am doing but will do it anyway. Oh help:rolleyes:

The stove is probably and I say this probably because I have not seen the stove. But is a 120/240 stove that requires from the panel a 3wire cable with a ground. 2hots which are black and red and a white which is the neutral and a green which is ground. The breaker better be a 2pole breaker. The heating elements probably require the 220 volts while the controls require 120 volts, thus the need for the 2 voltages. The white wire which is connected to the neutral bar in the panel will supply the return from which whatever hot leg the stove company chose to feed the control circuit with. The lights on the oven are 120 volts also again thus the need for 2 voltages. Good luck.

I just reread your post and suggest highly that you get an electrician to look at that. You confused me when you said you are throwing 2 different breakers and they are 55amp breakers.
 
Last edited:
jttheclockman said:
Another one of these I don't know what I am doing but will do it anyway. Oh help:rolleyes:

The stove is probably and I say this probably because I have not seen the stove. But is a 120/240 stove that requires from the panel a 3wire cable with a ground. 2hots which are black and red and a white which is the neutral and a green which is ground. The breaker better be a 2pole breaker. The heating elements probably require the 220 volts while the controls require 120 volts, thus the need for the 2 voltages. The white wire which is connected to the neutral bar in the panel will supply the return from which whatever hot leg the stove company chose to feed the control circuit with. The lights on the oven are 120 volts also again thus the need for 2 voltages. Good luck.

I just reread your post and suggest highly that you get an electrician to look at that. You confused me when you said you are throwing 2 different breakers and they are 55amp breakers.
Click to expand...

Ah, the back ground man. Say, the breaker are two 110v 50 amp. breakers tied together with a black bar that evidently came with the breaker unit. Two 110v 50 amp breakers serving a 220v range.
When you are on social security, the medical professional having taken the majority of our retirement savings, you study and take risks. Cannot afford to hire a electrician. I can, be careful and ask for help.
 
John T. knows what he is talking about. Your oven should get all its power from the two ganged 50A breakers, each one controlling one leg of the 240 V circuit. Each leg is 120V relative to neutral, but they are 180 degrees out of phase with each other, so the voltage difference between them is always 240 V.

Both these legs need to be brought to your oven. Often, builders will use aluminum wire to run these circuits to the oven location, since it's cheaper than using copper wire in these high amp applications. That may be why the wire gauge looks bigger coming from the breaker panel than the wires that come from the oven (which are probably copper, hence can be a smaller gauge). As John said, you also need the neutral white wire so the oven can also use one of the 240 V legs for its 120 V supply. You also need a green ground wire for safety (this wire never intentionally carries a current).

If you do need to connect aluminum and copper wire together, make sure you use the special connectors designed specifically for this application. This helps avoid the galvanic corrosion that will occur otherwise.

I'm not an electrician, so take anything I say with several grains of salt.
 
Breaker

He said it was 220 capped together so they operated together - nothing unusual there that's what a 50 amp 220 breaker looks like.

If the appliance leads are black red white and ground it wants a standard 220 connection - black to black, red to red, white to white and ground to ground. The wires will be sized to an appliance and the original was probably sized to a range. It is ok and safe to feed an appliance with an oversized feed, you can't use an undersized feed safely though. You might want to get a smaller 220 breaker your appliance does not seem to be designed for 50 amp protection check the manual.
 
Smitty37 said:
He said it was 220 capped together so they operated together - nothing unusual there that's what a 50 amp 220 breaker looks like.

If the appliance leads are black red white and ground it wants a standard 220 connection - black to black, red to red, white to white and ground to ground. The wires will be sized to an appliance and the original was probably sized to a range. It is ok and safe to feed an appliance with an oversized feed, you can't use an undersized feed safely though. You might want to get a smaller 220 breaker your appliance does not seem to be designed for 50 amp protection check the manual.
Click to expand...



What he said was confusing that is why I backed off what I said because if you look at his post he said they were so-called capped off (we in the industry call that tied together or ganged together) He then went on to say that he turned one 110 volt breaker on and got a slow warm up and that he proceding to go and turn the other on. That does not sound like they are tied together to me. You should not be able to do this if it is a double pole breaker which is what is needed.

I am also lost in the fact is this stove a replacement from what was there??? If so the amperage draw on this unit could be alot different than what was there. Nowhere did I see any mention of amperage on the unit being wired. The breaker could very well be too large for what is being connected. Nowhere did I read about the use of aluminum wire opposed to copper wire. Another set of conditions arise if that is the case.

Being on a fixed budget is definetly not a good excuse for doing shabby electrical work. I hope I am wrong and you do get this worked out John and I wish you the best of luck but my advise stands get someone experienced to look at it. I have said this time and time again so much is left out when someone wants electrical help and comes to a forum to ask for it. I am stepping away from this discussion now. Good luck.
 
John T. has it correct. From what has transpired so far here, no qualified electrician would make any recommendation except to call in a licensed qualified electrician to complete the hookup. The breaker question, the wire type and size question and the amp draw question of the stove make this very unsafe to even talk about on forum. We like you. Please, PLEASE contact an electrician. John, get online, go to IBEW.ORG and look up a local in your area. Contact the JATC director at that local and ask if he would send a good apprentice over to help you. Some times they will help senior citizens with small jobs such as you have for little or even free. It is worth asking, much better than killing yourself or burning your house down with your family inside.
Charles
 
True enough

ctubbs said:
John T. has it correct. From what has transpired so far here, no qualified electrician would make any recommendation except to call in a licensed qualified electrician to complete the hookup. The breaker question, the wire type and size question and the amp draw question of the stove make this very unsafe to even talk about on forum. We like you. Please, PLEASE contact an electrician. John, get online, go to IBEW.ORG and look up a local in your area. Contact the JATC director at that local and ask if he would send a good apprentice over to help you. Some times they will help senior citizens with small jobs such as you have for little or even free. It is worth asking, much better than killing yourself or burning your house down with your family inside.
Charles
Click to expand...

Charles any qualified electrician will quite properly tell do-it-yourselfers to get a qualified electrician to work on any home electricial problem. And that is exactly what they should tell them, electricity is nothing to fool with.

The problem is that this man has already said he ain't gonna do that. So now we want to help him out if we can. There is no question in my mind that a 50 amp breaker whether ganged or a single unit is too big to offer real protection but he probably won't buy a new breaker either.
 
You must log in or register to reply here.
Back
Top Bottom