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Question I have read some of the prior questions in this category and these provided some help but I would like clarification.
I am installing a Built-in oven and it lists the electrical requirements at 3.0 KW, 60 Hz and 120/240. I currently have a regular range that is running from a 3-wire #6gauge to 50amp breaker.
Question 1. Is this 50amp to large for the new oven?
The existing wiring does not have a dedicated ground and the directions with the new oven indicate that I could run the three wires to the new oven by hooking the oven ground and neutral to the neutral wire from the incoming line. Question #2. Should I attempt to run all new wires so there is a dedicated ground. Or can I run a separate ground wire?
Question #3 If I keep the existing wire and it is not long enough to get to the new oven location I was planning on using a junction box to extend the line is this okay?
Thank you for your help.
Answer Hi Cory,
Most regular residential ovens typically draw from 11 - 15 kW and are on 50 or 60 amp breakers and #6 copper. Based on your description...you are replacing a standard oven with a built-in which has a much lower power requirement.
This 3 kW oven can be ran with 10/3 with ground...on a 2 pole 30 amp breaker. If you attempt to use the existing wiring and breaker....not only will you be over-sized - you will not have the proper protection and serious damage could result in the event of a problem with the unit (the 50 amp breaker would not trip).
Based on the electrical data you supplied - I'd recomend replacing the wire with 10/3 w/ground.....and installing a 2 pole 30 amp breaker (unless the oven's manual specs a 2 pole 20 amp is adequate)
I do not recommend splicing at a junction box to add length to the wire with loads of this size. If all new 10/3 w/gr wire is ran - you should buy sufficent length so that splicing is not necessary. Under the new Codes....all ovens (and dryers)installed in new construction now require a seperate ground....the bonding of the ground to neutral is no longer permitted. (NOTE - this applies only to NEW construction....existing homes are grand-fathered. But - where you will need to run new wire - it is adviseable to install it to meet the current Code requirements)
With this in mind - the answers to your questions are:
1). Yes....the 50 amp circuit is too large.
2). Yes....new 10/3 w/gr. wire should be ran and a 2 pole 30 amp breaker used (unless specs suggest a 2 pole 20)
3). the existing wiring should be removed or disconnected at both ends.(in case you go back to a standard oven in the future)
Hope this helps....if you need more details, please follow up.
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