Neutrals Question...

hogdogs

I just got 2 deep fryers for the pool deck. They are 110v. I realized late that the amp draw for them would be too much for a single duplex outlet on a 20 amp circuit. I was able to break the tab on the outlet and use a spare conductor to have two 110v 20a circuits, one to top and one to bottom of outlet. My question is this... I only have the one neutral in the j-box. will it be overloaded or will it be fine. I hate to have to bring another neutral to the box as it will require wall demolition and that includes some nice tile work. Currently (no pun intended) I have one neutral going to combined/adjoined side of the duplex, and 2 conductors going to the 2 hot screws with the 2 outlets separated on the hot side only.


Brent

joed

It will be fine if the two hots are connected to a double pole 240 volt breaker to get 240 volts between the hots. In this case the neutral will only carry to current difference between the hots.
All three conductors must be in the same cable as well. You can't just grab a hot wire from another circuit.

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Jim Port

This just got to be a very expensive endeavor if the receptacle is outside. Outside receptacles need to be GFI protected. Double pole GFI breakers are not cheap. You cannot use a GFI receptacle on two circuits like you have.

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Answers based on the National Electrical Code. Local amendments may apply. Check with your local building officials.

hogdogs

Why a double pole 240v breaker? Why not use the 2) 20a 110v breakers? One half of the duplex is on one 20a 110v and the other is on a another... I have 2 fryers consuming 15 or so amps each. The house is custom and no Romex used... We spec'ed EMT and nothing under 12 awg and 20a breakers thru out. The conduit had one neutral from the panel and 3 conductors. I was able to add a another conductor from a very little used circuit to this duplex but adding another neutral would still be feeding from the one in the attic j-box from the panel.

Brent

Jim Port

The NEC requires that multiwire branch circuit have a common means of disconnect. A two pole breaker also ensures that the circuits are on opposite legs of the panel to avoid overloading the neutral.

How far are these receptacles away from the water?

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Answers based on the National Electrical Code. Local amendments may apply. Check with your local building officials.

hogdogs

Should have been more clear... The "deck" is considered "dry" as I have a second set of sliding glass doors to close off the elevated recreation area from the pool deck. No outlet is within 30+ feet of a water source.
All the "double pole breakers" I see have both halves on the same hot "bar". So what creates the neutral overload? In theory only... does the neutral see higher amps if both circuits are on the left or right hot leg? Would it be reduced if one circuit is on the left bar and the other on the right?

Thanks again,
Brent

nap

especially because of your situation, you need to be sure the hot conductors are from opposing legs of the panel. In the 3 conductor count, are you including the egc? if not, what were the 3 conductors already in the box?

If you have conduit, there surely should be no demo to add a neutral. All junction boxes must be accessible without demo so since you have conduit, it would simply be opening j boxes and feeding the neutral through to the outside j box.

AllanJ

The hot conductor from the very little used circuit must use the neutral from the same (very little used) circuit. Can you add a neutral at least that far, to said little used circuit?

Then attach the second neutral to the same half of duplex receptacle as the matching hot and break off the tab between the neutral screws also. Neutrals from two different sources are not tied together in an outlet box or junction box.

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Scuba_Dave

Actually by code an outlet IS required within 6-20' of the pool area
No closer then 6'
680.22

One thing my Inspector noted I needed to fix
I had an outlet just outside the pool area
The outlet is supposedly so that no-one will need to run extension cords
I've actually installed 4 outlets along 2 sides of the pool for general use
No closer then 10' to the pool

nap

If each pole is on a opposing leg, the current on the two hot conductors oppose each other. Due to that, the only current the neutral carries is the unbalance load of the two hot conductors (if both are being used) or the full current of the one hot conductor (if only one circuit is being used).

If you use circuits from the same leg of the panel, the current is additive so having 2 20 amp circuits, you could end up with 40 amps of current on the neutral.

frenchelectrican

There are couple items it have to be addressed .,


All outdoor receptales must have RCD { GFCI } it do not matter if single circuit or MWBC { MultiWire Branch Circuit }

{ pay attetion to the 2008 NEC code they change a bit on this one all the 240 volt outdoor circuit are now required it I know you will say Eh ? but they change that on Pool/ Spa part so it carried over to outdoors receptales as well }

Second thing with MWBC you must have same netural as two hot circuits no grabbing from somewhere else.

I know you mention conduit so that is the best route to pull in new MWBC you can not run split receptale at all on outdoor unless you have RCD breaker for it.

otherwise run new hot and netural on seperated circuit and add second RCD receptale next to the first one that is one of few legit way you can deal with it.

Oh yeah I hope you have fire extisghener in your area due you have deep fryers.

If you have GE load centre they are little tricky to deal with it.
If that the case we will give you a special instruction how dealt with it.


Merci.
Marc