I'm installing a kitchenaid double wall oven and also running a new circuit for it. Its model number is KEBS209B. I consulted two local electricians and they said a 40amp circuit with 8/3 wire will be fine.. but, when I do research online, I se that perhaps I should have used 6/3 wire instead?

Length of the run was about 85 feet.

Any guidance would be appreciated.

 

I don't see anything that makes me think you need a 50 or 60 amp circuit.

 

I over analyze and read too much and it gets the better of me. I was concerned about the length of the run of 8/3 wire (voltage drop after 96 feet) since I was coming close to that threshold. And then I read that 6/3 would potentially be better, blah blah blah, yada yada etc.

I drive myself in circles.

 

I would just run the #8. If the oven is straight 240 you only need 8-2 with ground, not 8-3 with ground.

 

I'm running 8/3 and a double-pole 40 amp breaker. Wouldn't a single pole 40 amp breaker only give me 120volts?

 

You only need 2 conductors +ground for 240*. The conductors in 8-2 go to the two poles of the breaker. The white wire is remarked black (or red or any color but gray or green) on both ends using bands of colored tape or felt tip marker. (In Canada use cable intended for 240v. No remarking needed).

*3-conductor is used for 120/240 where a neutral is required. If you used 8-3 for this the white wire is not used.

 

I actually just updated my profile just before replying.

Damn. I could have saved myself some effort and a few bucks with going for 8/2 then. Oy vey! That makes sense now.

I know what I know and more importantly, I know what I don't know, thus I ask.

So if I may ask, *if* I had connected BLACK to one pole of a 40 AMP breaker, and RED to the other pole of the 40 AMP breaker, and both green and white to ground.

.. and then at the oven side hooked it up the same way as per the diagram, would that have been ok?

The 3 and 4 wire directions both mention a RED cable, but I guess in the 3 wire US directions, we would be using a WHITE as the RED as you said. And the 3 wire is allowed since we ground through neutral....

It's all coming together now...

 

The white is only needed if there is also a 120 volt component in the oven. If not needed the white would just be capped at both ends.