[Trippwyre]

I am replacing an Induction Cooktop. The old cooktop had 3 wires: Black, Red & Bare. The new cooktop has 3 much thicker wires: Black, White & Green.

The old cooktop the bare was connected to the ground bus, the black to the top post of a 40A breaker and the red to the bottom post of a 40A breaker.

both have a rubber coating over the metal conduit which seems to prevent the sheathing to come in contact with the sub-panel.

How do I connect the new cooktop which has White Black and Green Wires which are twice as thick as the wires from the previous cooktop?


Old Cooktop:
Ancona AN-2401 - https://anconahome.com/products/ancona-elite-30-inch-induction-cooktop
Manual - https://cdn.shopify.com/s/files/1/2159/8609/files/AN-2401-EN-MANUAL-01.pdf?701



New Cooktop:
Forno FCTIN0539-30 - https://forno.ca/produit/ctmfn00504/
Manual - https://forno.ca/wp-content/uploads/2019/10/FCTIN0539-30_EN.pdf

 

[joed]

Connect the white as if it was the red of the old cook top.

That would black and white to the breaker and ground to the ground bus.

 

[Trippwyre]

Why is the 2nd Hot Wire (white) not Red?

Is that something to do with it being an Italian company it is made by? (Forno)

 

[Jim Port]

The tape around the conduit should be removed and the proper connector used.

 

[Trippwyre]

The tape around the conduit should be removed and the proper connector used.

I can slide the outer shell back and it's a solid piece of black cable all the way back. There is no tape. There is a length of heat shrink at the end of the metal sheath.

The black cable is solid and the 3 wires are within it. (..it's not a tube.. it's like the black part of the cable was poured over the wires.. it's solid)

 

[joed]

Why is the 2nd Hot Wire (white) not Red?

Is that something to do with it being an Italian company it is made by? (Forno)

Because it's cheaper to get black and white cable than black and red?

 

[Wiredindallas]

To us white for a hot is odd, but to get the stated 240 volts put the white on the breaker. In Europe 240 volts is standard so perhaps they do not even have a neutral as we know it.

 

[NCmountainCabin]

the colors of the wires does not matter - both the red and black, or the white and black, carry the POWER, while the bare and green are ground - no NEUTRAL is used, which is the typical 'white' that most of us think of here in the U.S...

the reason that this is a 3-wire setup, where no neutral is used, is that both HOT wires always pull the same amount of power, at the same time. There's no need for a neutral wire to 'balance' the load between them. This is like some of the older Clothes Dryers, which used the same two hot and one ground wiring scheme, and most battery powered car chargers, like our Nissan Leaf, which do the same.

It's confusing sometimes to think that no Neutral is needed, since we see this 'white' wire all the time on the regular household outlets we plug into, but 240v service doesn't always need the use of the Neutral.
Even when you look at how to wire a 'sub-panel', the electrical 'rules' require that the Ground AND the Neutral wires all terminate TOGETHER on a common 'ground buss' at the panel. So, essentially, they are all tied together, whether ground, or neutral.

 

[afjes2015]

...
It's confusing sometimes to think that no Neutral is needed, since we see this 'white' wire all the time on the regular household outlets we plug into, but 240v service doesn't always need the use of the Neutral.
Even when you look at how to wire a 'sub-panel', the electrical 'rules' require that the Ground AND the Neutral wires all terminate TOGETHER on a common 'ground buss' at the panel. So, essentially, they are all tied together, whether ground, or neutral.

I believe this may confuse the OP a bit.


A neutral is not needed on a 240v unit. It is needed on a 120/240v unit.
Voltage does not know the color of the insulation on the wire.


On a sub panel the neutral and ground are to be separate. The ground to be bonded to the panel and the neutral isolated from the ground/panel.

 

[huesmann]

Found this set of instructions for a different Forno cooktop: https://forno.ca/wp-content/uploads/2017/09/30-EN.pdf

Other than being upside down compared to the OP's, they're basically identical aside from the color they ask for, i.e. white and red are equivalent. I see no issue just connecting the white cooktop wire and red supply wire.

 

[NCmountainCabin]

...


On a sub panel the neutral and ground are to be separate. The ground to be bonded to the panel and the neutral isolated from the ground/panel.

Sub-panels are not to be separated, Neutral from Ground, that's only on the main panel itself...sub-panels use a common buss-bar for both.

 

[Reddog5522]

Sub-panels are not to be separated, Neutral from Ground, that's only on the main panel itself...sub-panels use a common buss-bar for both.

Sub panels MUST HAVE SEPARATE GROUNDS AND NEUTRALS

 

[NCmountainCabin]

my apologies, you are correct - keep up the good work!

 

[Oldmaster]

Sorry NC
Eguiptment grounds and neutrals are always seperated in a sub panel. Otherwise any ground fault current in sub panel would travel back to original overcurrent protection through neutral which is high resistance. Always seperate.

 

[NCmountainCabin]

right, and I should have reiterated the same, but my confusion came from my memory : /

recently, we moved from a private site where I had our RVs attached to a MAIN PANEL, where the grounds and neutrals were mixed...

more recently, though, the move to the new private site had access to a SUB-PANEL, where, YES, the grounds and neutrals are separate - sorry for my memory confusion.


: )

 

[seharper]

Why is the 2nd Hot Wire (white) not Red?

Is that something to do with it being an Italian company it is made by? (Forno)

No, the technique is American enough. Cables are made in standard colors, either black/white/ground or black/white/red/ground. On 240V applications that don't need neutral, they use the lesser cable and simply re-identify the white to be the other hot.

By "re-identify" I mean mark the white wire with e.g. red tape.

Re-identifying is a Code requirement. I have no idea how UL or ETL approved this thing without that. Since it was overlooked, you should mark the white with red tape. At that point everything will make perfect sense.

I like it when things make perfect sense.

Speaking of that, if UL approved the goofy halfway-armoring and cable jacketing, it's good.

 

[jeffnc]

I believe this may confuse the OP a bit.

I agree that was rather muddled.


Electricity has to "flow". In a normal US 120v setup, the current comes in on the hot black wire, but it needs some place to go, so the white wire is provided as a passive wire to accept the current flow. (Neutral is another name for passive in this case.) You might say this is a little analogous to water coming through your faucet under pressure, and just running down the drain passively. The supply pipe coming into your faucet is like the black wire, and the drain pipe is like the white wire. That would be about how it works with DC (direct current).



But we have AC (alternating current), so the hot wire pushes then pulls alternately. This is analogous to a lumberjack using a 2 handed saw. He pushes then pulls, and no one is using the other handle. His handle is the active side, the unused handle is the passive side.


The voltage coming into your house is 240. By using one hot wire, you are using only half of it. Your oven uses the whole 240 so you get double the power. One side pulls while the other pushes, and then one side pushes while the other pulls. Both sides are active, like a 2 man saw with 2 men each holding a handle. One pushes while the other pulls, and then vice versa.

So really the question should be, why do we use only half our power at 120v when 240 is coming into our houses? Why do we go to the trouble of inventing this "neutral" wire in the first place? I believe it had to do with electric light bulbs when they were first invented. The early technology couldn't handle 240v very well. Wiring would probably be more simple without that change.

 

[jeffnc]

It's confusing sometimes to think that no Neutral is needed, since we see this 'white' wire all the time on the regular household outlets we plug into, but 240v service doesn't always need the use of the Neutral.

What do you mean "doesn't always"?

 

[betelgeuse]

In Europe 240 volts is standard so perhaps they do not even have a neutral as we know it.

In Europe 240V is not standard for residential . Most European countries use 230V (50Hz). and they do have a neutral.



They're 230V phase to neutral, and 400V phase to phase.

 

[seharper]

To us white for a hot is odd, but to get the stated 240 volts put the white on the breaker. In Europe 240 volts is standard so perhaps they do not even have a neutral as we know it.

The older areas of the Philippines are exactly like you're thinking - North American 120/240V and delete the neutral.

On the European system they did two things. #1 they switched it up to 3-phase, like our 120/208V in apartment buildings in NYC. And #2 they doubled the voltage, so it's 240V (230V outside UK) leg-neutral. Most houses only get 1 phase, but some with larger needs get 2 or all 3.