Please help me figure out amperage for the oven

tunafish76December 26, 2012

A newbie needs some help here. I'm puzzled by the instruction manual of the oven I got. The oven in question is kuppersbusch 9800.5MX. it has a 3 wire 240 volt connection, red grey and a green/yellow. My understanding it could be wired with a 2 wire and a ground 240 single phase service. the color grey and not black for the wire is my first concern. The conduit coming from the oven has 14GA wires. The "Maximum Power" listed on the oven is 3850W. 240V, 60Hz. the instruction says the oven "is run on a industry low 15A service" and here is where I'm puzzled again. If I calculate the amperage using the ohms law it comes to 3850/240=16A. Why do they say the fuse amperge is 15A? Because of NAC table 220.55 listing the demand for this type of ovens at 80%??? Bottom line is it safe in your opinion to put it on the 15A breaker? I was going to run a dedicated circuit using 12-2 romex tot he junction box (just in case i would need a 20A in the future.
2. I also have thermador steam oven rated at 240V/15A. What breaker do I need for its circuit - 15A?
3. I'm replacing my electric range with a gas range so i will have a free 40A dedicated circuit. NEC says that you can branch circuit wall ovens - is it wise/safe to use this circuit and tap two 12-2 wires into it for my above ovens, or is it better to run 2 additional individual circuits and leave this 40A as is. I was just wondering if a 15A oven shorts would it be enough to trip 40A breaker? thanks a lot

Thank you for reporting this comment. Undo
mike_kaiser_gw

1.) Page 5 of the installation manual says the oven requires a 120/240v, 3-wire with ground circuit fused at 15 amps. The manual also says 3.6kW (3600 watts / 240 volts = 15 amps). In any case, you'll need 3 wire plus ground cable. You might want to give the German engineers a call and see if they have any explanation. ;-)

Frankly the "industry low 15 amp" stuff sounds like a bunch of marketing bovine defecation to me. Smaller wire is a little cheaper but watts are watts.

2.) A double pole, 15 amp breaker.

3.) Not sure about that one. Ron or Pete will be along soon.

    Bookmark   December 26, 2012 at 10:51PM
Thank you for reporting this comment. Undo
tunafish76

Thanks for the reply, Mike. The 3 wire with ground was a 9800.0MX in 9800.5MX they went with 3 wires (go figure) and the manual that has infor for UK and Ireland only. Since it clearly says 60Hz and has USA on the box I assumed the stove is made for US market. Emailed to Germany already to no avail. USA rep said "people put them on different breakers" I just hope this darn thing cooks well when I hook it up. Otherwise it is pain in a rear

    Bookmark   December 27, 2012 at 12:52AM
Thank you for reporting this comment. Undo
mike_kaiser_gw

From what I saw this oven is expensive and one would hope you'd get a bit more support from the manufacturer. Given the information you have, I'd probably use 12 gauge wire and a 20 amp breaker. You could start with a 15 amp breaker and see if you experience any nuisance tripping and then switch to a 20 amp if necessary (using 12 gauge wire to run the circuit). Breakers aren't very expensive.

    Bookmark   December 27, 2012 at 12:04PM
Thank you for reporting this comment. Undo
weedmeister

I'm not going to search for you, but I seem to remember someone here having essentially the same question not too long ago. That is, installation of two Gagg ovens with an existing single oven/range circuit in place. I don't remember the consensus.

    Bookmark   December 27, 2012 at 3:42PM
Thank you for reporting this comment. Undo
Ron Natalie

You could (if you complied with other requirements) tap a 50A range circuit for multiple units. This however is only 40A.

    Bookmark   December 27, 2012 at 4:30PM
Thank you for reporting this comment. Undo
tunafish76

they left the us market, therefore the customer service is not top notch if it ever was. I will try to do exactly what you suggested. After all NEC table does list demand factor at 80% for the ovens less then 8kW

    Bookmark   December 27, 2012 at 4:47PM
Sign Up to comment
More Discussions
Well this sucks
Just when you thought the idiot popup ads in the gardenweb...
Ron Natalie
Need help with a rocker switch
I need to replace it in our SunHeat radiant room heater....
bold_as_love
Motion sensor that doesn't click
I have a motion sensor very much like the picture attached...
drmeow3
Help with 240V 50A location
I'm trying to do a challenging kitchen layout. I will...
12crumbles
Doorbell goes off by itself.
Can anyone tell me why this would happen? It's a wired...
stu2900
People viewed this after searching for:
© 2015 Houzz Inc. Houzz® The new way to design your home™