Extending Electrical Wire

[premiso]

Hi all,

I am working on a project to move my dryer and washer to the basement. I know the dryer needs to go on a 210 dedicated circuit. Currently the outlet is about 8 feet from where it needs to be, and I do not know if I have enough length to get it to where it should go. I am wondering what the best route to extend the circuit is, if a junction box would be allowed. I have easy access to where the wire is and where it needs to go as it is all unfinished and not enclosed off. The junction box would be put in a furnace room and left accessible as required. I just do not know if that would hinder and or effect the circuit in any way negatively.

Appreciate any insight, thanks!

[suemarkp]

Extending it is OK. But, if you have an old 3-wire dryer circuit (hot, hot, neutral), if you extend it or put in a new one you need a 4-wire circuit (hot-hot-neutral-ground). That could be difficult to fix if you have an old 3-wire circuit (difficult to run a separate ground from panel to the old outlet location).

So the best solution is a new 10-3 w/ground cable from the panel to the new location. If you have a 4 prong dryer outlet now, then extending it is easy and you'll need a box that has 20 cubic inches of volume in order to splice those wires. If you have a 3-prong dryer outlet now, and running a new cable is impossible, your only choice is to run a single #10 green or bare copper wire as close as possible to the path of the existing dryer cable. That ground wire needs to go through the same knockout in the panel and outlet box as the existing cable if they are metal.

If you change to a 4-prong receptacle, you'll need a new 4-prong cord for the dryer which requires removing the chassis to neutral bonding jumper at the dryer itself.

[premiso]

Thanks for the extensive information!

I bet I do have the old 3 prong system, unfortunately. I will look into seeing how difficult it will be to run a new wire.

Thanks!

[Electrician Wannabe]

Can someone explain why they now require a 4 prong for electric dryers. Its obviously got to be some safety issue, but what it is eludes me. I don't see how separating the ground and neutral provides you any extra protection when the ground and neutral are tied together anyway in the service panel.

Just curious. I'm sure I'm missing something obvious.

[junkcollector]

Can someone explain why they now require a 4 prong for electric dryers. Its obviously got to be some safety issue, but what it is eludes me. I don't see how separating the ground and neutral provides you any extra protection when the ground and neutral are tied together anyway in the service panel.


It is because if the neutral becomes disconnected or open, and there is a ground fault, the ground is still there to clear the fault. (trip the breaker) Since a 3 wire dryer circuit shares its ground / neutral, if you lose neutral you also lose ground.

Trailer houses are wired the same way. It is to prevent a bad neutral from causing the skin of the trailer to become energized.

[Electrician Wannabe]

That makes sense, but now I am compelled to ask do neutrals normally come lose or open? Is this really a problem?

Thanks

[suemarkp]

It doesn't happen very often, especially if there are no splices in it. But it could happen and then you get shocked when you use the appliance. It is more common for the neutral that feeds the whole house to come loose. This is still a hazard, but you get a lot of visual warnings with some lights getting brighter and some getting dimmer, and appliances running faster or slower or burning up.

[junkcollector]

but now I am compelled to ask do neutrals normally come lose or open? Is this really a problem?


Opens can happen in either wire(s) But, if the either of the hots became open, there really would be no hazard. No voltage would (should) be present at the point of utilization; there just would be no power. There is much more of a hazard present with a neutral or ground problem. Grounding keeps all metal parts at the same potential, therefore negligible shock hazard.

Now if we start talking about a loose service neutral, well that has altogether different serious consequences.