[pretzladay]

I am replacing a Baker's Pride oven. The old one had a 4-wire power cord to a 4-prong receptacle. New one had just a 3-wire power cord(single phase?), with black wire to one outside terminal, white wire to middle terminal, and green wire to ground. The other outside terminal was blank; no wires leading to internal circuits. Since store opening time was only an hour away, I installed the old 4-wire power cord on the new oven, connecting the black, white, and green wires to duplicate the 3-wire cord, and connecting the red wire to the blank terminal. Oven operates, but seems underpowered. Did I do right?

[ma0641]

Is this a 240VAC stove? The old wiring indicates 120/240 while the new wiring indicates 120VAC. Where are you located? Single or double breaker?

[drtom4444]

Sounds like the new oven is only getting 120 volts which will burn it up really fast. You need two hot wires going into oven for 240 volts. The 4-wire plug has two hot to get 240 volts plus two grounds. One ground is usually fine as long as you have the two hot wires correct. You need to use a meter to wire it right; any other way is just guessing and will cause problems. DrTom4444

[ma0641]

I was confused on this too; black, white and ground on an appliance is almost always 120VAC. Black white and ground at the supply could be 240VAC if the white is hot but not marked. That's fairly common for a Hot Water heater.

[drtom4444]

Take a meter and find out where the 240 volts is coming from, then look on wiring diagram and find out which terminals need to get 240 volts. Wire it so that the oven gets 240 volts. It's really simple, but you need a meter because anything can change from the time the power leaves the panel box. DrTom4444

[drtom4444]

One thing to note: L1 and L2 are you power connections in the oven. If you have L1, L2, and L3 you have a 3-phase oven and will have to change the wiring from the panel box to give you 3 hot wires. Then you will have to see if fan is turning in the right direction and if not reverse two wires. See wiring diagrams at: http://www.bakerspride.com/manuals/Inst-Op/English/EP-2-2828%20Inst-Op.pdf If I was you I would just call an electrician if this confuses you. DrTom4444

[pretzladay]

The new oven is a P-44S, 208v, 1 phase. The cord that came with it had only 3 wires: black to top terminal, white to middle, and green to ground. The bottom power terminal is blank. I thought I was getting an oven identical to the old.
The ID plate on the old one identifies it as a P-44S, 208v, and 7200w, but doesn't indicate number of phases. The receptacle is wired to a double breaker, and the power cord had 4 wires: black and red to the outside terminals, white to the middle terminal and green to ground.
Under the gun, I swapped power cords, running 4 wires, black to top, white to middle, green to ground, and red to the blank bottom terminal.
I've been reading articles on converting 4-wire dryers to 3-wire that say to run a grounding strip from the neutral terminal to the ground screw.
Thanks for your help.

[drtom4444]

208 volt is usually 3-phase. Check this out a little better. Email me at [email protected]. DrTom4444

[ma0641]

Gee that would have helped a long time ago! 208 is not a normal home voltage. You will most likely need to get an electrician in.

[tkrussell]

208 volt single phase is popular in large apartment buildings, the Main Service is 120/208 volt 3 phase, and then 120/208 volt is delivered to each apartment.

What is not know yet from pretzladay is what is the supply voltage.

It is possible that a new 208 volt unit is not powered by 240 volts, which will void the UL listing of the unit, void the warrnty ,and the higher voltage may shorten the life of the appliance.

[pretzladay]

The oven is in a mall shop, probably the same power distribution as in a large apartment. Does that get me any closer to a fix? Can I rearrange the wiring at the oven terminals to make a 4-wire receptacle work, or will I have to rewire the receptacle?

[tkrussell]

OK I think I see what you did:

black wire to one outside terminal, white wire to middle terminal, and green wire to ground

The four wire receptacle should have two hots, brass terminal, one neutral, silver terminal, and a green terminal for the ground.

If you connected the oven to one brass and the silver, you have miswired it, you should read 120 volts across the two terminals you used.

This would answer why the unit is not working properly.

You need to connect the two hot wires from the unit to the two hot wires in the receptacle to get 208 volts to the unit. You can ignore the white neutal in the receptacle.

[pretzladay]

OK! Let me go through this to be sure I have understood correctly. At the back of the oven, I will connect the 4-wire cord as follows: black (hot) wire to outside (hot) terminal, red (hot) wire to middle (neutral) terminal, green wire to ground lug, white (neutral) wire tied off, and no wire to the 2nd outside terminal, which is a dummy terminal anyway.
Is it really this simple??
Baker's Pride could not/would not attempt to solve this for me. They referred me to a local approved service company that listened to my problem on the phone, said they would have to call me back, and haven't.
Anyway, unless somebody jumps on here and says "No, you didn't understand correctly," this is how I'm going to rewire the oven tonight.
Thank you all so much!

[tkrussell]

Since the oven is straight 208 volt, sounds like you only have the three terminals in the unit, and sounds like you will connect it properly.

[pretzladay]

Oven is working great! Thank you, tkrussel, and all who responded!