electrician help! double oven junct box

[Gogar]

Originally Posted by nota

BUT THE GROUND AND THE NEUTRAL WIRES DO CONNECT TO THE GROUND AT THE BOX
so what is the point of the 4th wire ?
and why is it claimed to be safer ?

4-conductor run is code, and it's also common sense for some oven in the future that needs it. Proper neutral wiring is important these days.

Improper wiring might get hot and make your 25,000 pound plywood roof catch on fire.

[dad911]

Originally Posted by nota

BUT THE GROUND AND THE NEUTRAL WIRES DO CONNECT TO THE GROUND AT THE BOX
so what is the point of the 4th wire ?
and why is it claimed to be safer ?

NEUTRAL ISNT A GORUOND IT IS A RETURN PATH FOR CURRENT. GrOuNd is for Safety.

By your logic, a 3 prong 120v receptacle would not need a white(neutral) wire either, they are(possibly) connected together in the panel.

For everyone else:
While they may connect in a "main" panel, they do very different things. And they do not connect in a sub-panel(although I find them interchanged all the time)

1) It's code now. NEC (National Electric code)
2) Boards, timers, lights may need 120 in newer ovens. That requires a neutral, return path for 120 circuits.
3) Did I mention it's code?

250.140 Frames of Ranges and Clothes Dryers. Frames
of electric ranges, wall-mounted ovens, counter-mounted
cooking units, clothes dryers, and outlet or junction boxes
that are part of the circuit for these appliances shall be
connected to the equipment grounding conductor in the
manner specified by 250.134 or 250.138.

[Zeke]

3 words, look them up: Equipment Grounding Connector. The difference in the OP's situation is that the frame of the oven is grounded in addition to the neutral which is returning some current back the earth. At the service entrance the EGC is bonded to the neutral buss and to a ground rod or 2, plus UFER ground (rebar in concrete set in soil) and possibly plumbing if the plumbing has potential (current carrying ability).

Also, in the same scenario, the neutral (and bonded buss) are connected to the service transformer via the service entrance.

So what? Well, if the neutral is interrupted... I'll let you take it from there. The long and short of it is that if one don't, the other one will.

[T77911S]

I always understand it as neutral is a current carrying conductor, the ground wire is not.


just a side note.
we were getting a little "tingle" when turning on lights in the "shed". found out they used the ground wire as the other conductor for a 3 way switch,. (IE they used 12/2 wire instead of 12/3), actually it may have been 14g.

they also ran 240 to the shed but used something like 6 or 8/2. again they used the ground wire as a current carrying wire for the 120v portion of the shed. the box they used was melted where the ground wire connected to it so bad I had to trash the box.

on my way to get new wire now.
later

[T77911S]

Split bolt connectors for connecting the wires?

Is there another option


Also considering replacing the aluminum wire out of the oven with coooer.
Any reason not to do that

[1990C4S]

Originally Posted by T77911S

I always understand it as neutral is a current carrying conductor, the ground wire is not.


just a side note.
we were getting a little "tingle" when turning on lights in the "shed". found out they used the ground wire as the other conductor for a 3 way switch,. (IE they used 12/2 wire instead of 12/3), actually it may have been 14g.

they also ran 240 to the shed but used something like 6 or 8/2. again they used the ground wire as a current carrying wire for the 120v portion of the shed. the box they used was melted where the ground wire connected to it so bad I had to trash the box.

on my way to get new wire now.
later

Where are you getting a tingle from? The electrical box?

It is uncommon, but you can get a floating neutral if you have a supply issue from the pole. Make sure you have zero volts neutral to ground. I've seen as high as 20 volts on a neutral coming into the breaker.

[MBAtarga]

Originally Posted by T77911S

Split bolt connectors for connecting the wires?

Is there another option

What wires are you attempting to splice? Aren't you running new cable from the panel to the junction box?

[T77911S]

Yes new 6/3

It’s cooper to aluminum

I have heard of a rubberized connector for copper to aluminum but forget what it’s called
Trying to look it up


Just not a fan of taping

[1990C4S]

You need NoAlox to join copper to aluminum wire.

[T77911S]

ah,
Polaris connectors. I have used/seen them before, just did not know what they were called.

those things aint cheap, $40 ea

[T77911S]

Here is the connection I came up with.
She used it last night but then I was moving the conduit and apparently one of the wires inside must have a nic in it because it shorted and pooped th breaker.
Now I have to pull that beast back out to inspect the wires

[dad911]

Did you make that whip? And did you use these insulators?

https://www.homedepot.com/p/3-8-in-Flexible-Metal-Conduit-FMC-Anti-Short-Bushing-35-Pack-75401/100170558

[Zeke]

I see daylight. What the Hill?

[T77911S]

daylight- I don't have sheetrock on the back side yet.

yes I did use an insulator. I even wrapped the wires with electrical tape at the end BEFORE I wired it.
I inspected the wires, it appears the nick is further inside the conduit.

I think they got nicked when installed at factory. then I wrapped each wire with tape and it tripped it again. that's why I think the bad spot is further inside.

you can see the burn mark where it arched when I moved it. (it actually did not trip the first time, just sparks).
I did not see any marks on the wires right there plus I already had tape at that end.
there was a nick on the red wire but I put heat shrink on it before wiring it up.

rotate the pic 90 CW.

[Zeke]

Daylight. Where's the box?

[T77911S]

oh, its back there, trust me,.
you can see the cover is screwed down.

[Zeke]

Originally Posted by T77911S

oh, its back there, trust me,.
you can see the cover is screwed down.

OK, now I see it. Good job!