How to make the electrical connections for a built-in electric cooktop 

It depends on the model of your cooktop check you install manually. The power cables are sold at appliance stores, Lowe’s, Home Depot, etc. There are different plug configurations so take a picture of what you have.

A pure 240V (2 phase) appliance does not use a neutral wire. The 2 “Hot” wires (usually Red & Black) are 180 degrees out of phase so the current flows from the electrical panel through the black wire to your appliance back to the box through the red wire and then reverses red-appliance-black-panel-black….. A 120V (single phase) appliance needs a way to complete the circuit so a neutral (usually white) wire is connected back to the box. The white and the green ground wire basically do the same thing where as the white wire is the normal path and the green is the oops something is wrong path and should trip the circuit breaker before damage to people or property. A 120V/240V appliances connect all four wires and will use the 2 hot wires (240V) to run the high-voltage heating elements and one of the hots and the neutral wire (120V) to operate vent fans, oven lights, etc. There is also usually transformers in your appliance that drop the voltage down and/or switches it to DC to operate, clocks, timers and digital displays. This is all done internally in your appliance.

Same problem. No house ground wire. So I am just putting the green wire to a screw of the box, although I don't know if the box is grounded. Or you can just leave the green wire unconnected, I guess.

Thank you for your question. For liability reasons, you need to follow the manufactures instructions and recommendations for circuit, breakers and wiring. If it’s new construction I would run the 6/4. It’s not that much more expensive while the walls exposed versus having to go back later. As far as the circuit breakers use what they recommend because that is your safety switch if there’s a problem with your appliance. You wouldn’t want to 60A circuit breaker on there and not have it trip. If this is old construction and you’re not changing out the wire, then never put a breaker on bigger than the wire capacity. I’m sorry I couldn’t be more help.

The gauge of the wires can be determined using a wire gauge which you can purchase at any hardware or electrical store for around $10. As far as determining if the wires are 120 or 240 you can use a voltmeter, but its really determined on how they’re hooked up back at the main electrical panel. If you’re not 100% sure you need to have a certified electrician check all the connections, you don’t want to hook something up and damage the appliance or worse cause a short and a possible fire at your house.

The amperage should be in your installation manual that came with the stove. Every stove is different, depending on the power requirements as far as what size circuit breaker you need. I would highly recommend you have a licensed electrician install the circuit breaker and wiring to the stove location. In this video I’m just demonstrating how to make the final connections after the drywall paint cabinets and cooktop were installed. You could also call electrician out to do the final connection but they usually charge $100-$200 just to show up.

The short answer is NO, do-not connect the white neutral and green(or bare) ground wires together. A pure 240V (2 phase) appliance does not use a neutral wire. The 2 “Hot” wires (usually Red & Black) are 180 degrees out of phase so the current flows from the electrical panel through the black wire to your appliance back to the box through the red wire and then reverses red-appliance-black-panel-black….. A 120V (single phase) appliance needs a way to complete the circuit so a neutral (usually white) wire is connected back to the box. The white and the green ground wire basically do the same thing where as the white wire is the normal path and the green is the oops something is wrong path and should trip the circuit breaker before damage to people or property. A 120V/240V appliances connect all four wires and will use the 2 hot wires (240V) to run the high-voltage heating elements and one of the hots and the neutral wire (120V) to operate vent fans, oven lights, etc. There is also usually transformers in your appliance that drop the voltage down and/or switches it to DC to operate, clocks, timers and digital displays. This is all done internally in your appliance.

I’m a little confused in your description you say “the new stove has a black, white and green”. That sounds like a 120V connection not at 240V. Please double check your install manual. If it is a 120V appliance, then you need to disconnect the white stove wire from the red and connect the whites together. You should then cap the red wire coming from the panel and change the circuit breaker in the box to a 120V using only the black wire. (check your appliance manual for the proper amperage needed). The red wire should be capped in the box also, and just pushed out of the way.

Thanks for answering. The specs on the drop in stove top says it’s 240V and the wiring diagram shows stove black to the breaker, white stove to the breaker and green (which they call earth) to ground wire. I want to use my tester on the ground to make sure green is not hot. I tried the stove and it worked with no errors or breaker tripping. The stove top is china made and induction where the pan gets hot when placed on the surface.

The stovetop has no light or timer for 120V usage. It has a digital display that worked with this connection

As long as you follow the wiring instructions you should be good. A wire is still just a wire the color of the jacket is just to help with identification. Just cap off the white neutral from the electrical panel and enjoy cooking on your new stove top.

You’re welcome

If the white is not used, then just cap it off with a wire nut and tuck it into the electrical outlet.

The cable does come right through the wall and into the cabinet. A box is required where you make the connections. If you already have a box in the wall, you can make the connections there or just add a box in front of it.

@@spacemanjohn6383 Thank you so much!

10 awg - 30 amp 8 awg - 40amp 6 awg - 50 amp You should always run the same size wire home run to the breaker and when your in a metal junction box always ground to the box

You should. This protects you from shock if a bare wire comes in contact with the metal junction box. If it’s a plastic box then no.

@@flyinghammerdiy4487 That's what I figured -- I just didn't see that done in your video, unless I missed it.

Most cooktops are hardwired, but you could add a plug if you wanted. It would be an extra expense and I’m not sure what the benefit would be.