Electric

[geomarq]

I have a very rookie electrical question RE THHN wire and electrical situation. I've never seen or used it before.

- I have a 160' run from the house electrical panel to the location of the pump/electrical.
- the town requires this type of wire in conduit
- I need a 230v plug for the pump (10g wire), a 120v outlet (12g. wire) and wiring for some lights (14g).
- So this means I need to run 9 total wires? They are all individual wires? This isn't like romex where all your wires are together in one jacket?

 

[bk406]

Since you want multiple circuits at different voltages and amps, the correct thing to do here is to install an outdoor subpanel. The idea is to run a set of 4 THHN wires from your main breaker box out to a subpanel located near the pump. The amount of current you need will be dicated by how much power you need at the subpanel. Beffore advice can be given on how big of a subpanel you need, we need to know what your pump draw will be (i.e. how big is your pump?), what you plan to have plugged into the 20 amp convience outlet, will you ever install an electrical heat pump, etc.

You can DYI this. However, are you going to get this permitted and inspected? Will the town allow you to do your own work and then have it inspected? From your basic questions, it seems you have not done a lot of electrical work before. How comfortable are you doing this?

 

[geomarq]

Pump is a 1HP, @ 230v it draws just 9-10 amps. Where & how would I put a subpanel? What size wire?

 

[bk406]

My advice, call an electrician. You would have to work in your main panel that will be hot and thats not something a novice should do. That being said, you probably want a 60 amp subpanel. Amps and distance run will dictate wire size for the panel. If you were just installing outlets or a switch, i'd say you could DYI some electrical without a lot of previous experience. A subpanel run for something like this does require a little more knowledge than i think you have. I'm not trying to talk down to you, its just that this kind of thing is more of an intermediate or advanced DYI project. If you really want to takle it, I suggest doing some google searches on subpanel installs, wire sizes for amps carried, etc and get a feel for what is required to do this.
One way you could save osme money is to run the conduit and pull the wire out to where you need the circuits, then hire an electrican to actually hook everything up.

 

[Bama Rambler]

THHN is a very common insulation type but that's the first time I've heard of a jurisdiction "requiring" it. They usually require that, or greater (i.e. THWN, XHHW). A sub panel is not a bad idea but if the three circuits are all you need and the distance from the panel isn't far, I'd just run the individual wiring from the house panel.

What makes you think you need 10awg wire for the 220v circuit?
How far is it to the equipment?

I'd run 12awg for everything and use different colored wires for each circuit to cut down any confusion.

 

[bk406]

Bama, his original post says the distance is 160 feet. Thats why i suggested a subpanel. Thats a long way to run 3 circuits from the main for something like this.

 

[Bama Rambler]

Sorry I missed that. I'll retract what I posted above and say go with a sub panel.

Your voltage drop wire size is gonna be huge if you go with individual circuits.

 

[geomarq]

I have a good amount of DIY electrical experience, but none with THHN and pools, thus my question.

1) RE the subpanel.. what gauage wire if a 60 amp panel considering the 160'distance/voltage drop issue? eight?
2) I'm assuming there are outdoor approved subpanel's? It will need to be supported to a p/t 4x4 (in the ground).. any issues with that?

Thx. again..

 

[bk406]

Yes, what Bama said.

As I said, I would install a 60 amp subpanel. Thats more than enough power to handle what you need out by the pool. A subpanel would mount on a wall near the pool, or in the absence of that, you could mount it on a post in a flowerbed and plant shrubs around it. It needs to be at least 10 feet form the pool. In any case, you would need #4 AWG wire (#6 would normally handle 60 amps, but not at that distance, the voltage drop would be too much. #8 wire is way too small for this application). A 60 amp breaker is put into the main, and four, #4 wires would be run to the subpanel through 1.5 inch conduit (2 inch might be better, but 1 inch is definately too small. You could also run #6 for the ground if you wanted).
As I said above, to save money, you could bury the conduit, pull the wires and be ready at both ends for an electrician to wire everything up. Subpanel wiring is a bit different than a main. You also need to unbond the ground bus from the neutral in the sub. Also, since this is a subpanel NOT located in the same structure as the main, your will need to run a #6 wire from the ground bus on the subpanel to a ground rod. If it were in the garage or in the house, a second ground rod would not be needed. But for this application, a second rod will need to be installed per NEC 250.

 

[Lershac]

Since this is going into a new construction structure, I will make you aware of something that almost bit me, so you can ask your inspectors. In our area, they NOW make you not only use a buried ground rod (that must be inspected, then covered so it will not be a future damage hazard), but they ALSO make you tie into the rebar in your slab into a piece that is a minimum 10' long and completely encased in the concrete slab. Now this is in MY area, it might not be that way in yours, but better to ask than to find out after and have to bust up a newly poured slab to make a connection.

 

[bk406]

Since this is going into a new construction structure, I will make you aware of something that almost bit me, so you can ask your inspectors. In our area, they NOW make you not only use a buried ground rod (that must be inspected, then covered so it will not be a future damage hazard), but they ALSO make you tie into the rebar in your slab into a piece that is a minimum 10' long and completely encased in the concrete slab. Now this is in MY area, it might not be that way in yours, but better to ask than to find out after and have to bust up a newly poured slab to make a connection.

Thats a good thing to remember. My jurisdiction is the same, but it only applies to a main panel. . If the sub is located in the same structure, no additional ground is need. A single ground rod is only needed on a sub if it's not in the same structure. Always wise to check with the local inspector though.