installing a indoor wall switch for pond lights

[waynefrcan]

Ok thks, now I have 50ft x 2 lines that I have scraped up, bent and unbent getting into the LB and about 10 ft of pvc. I'm thinking since they recommended the wrong size pvc, i should be able to return the wire. What about ground shifting etc, won't that put pressure on pvc pipe at elbows? Do you run the pvc in sand?

THks

 

[brandonsdad02]

No ground shifting won't hurt it. Unless you are digging this down 6ft the ground shifting won't be a issue. I would take the pvc back and buy the direct burial.

 

[waynefrcan]

Brandon, the H-depot guy that was against the 12/3 said it's because the return power on the neutral takes twice the load. IS that so bad?

The set up would be a 2 pole 15 amp breaker and either 14/3 or 12/3 wire. Distance from plugins to panel is 90 ft.

They will take back the wire so I'm thinking of 12/3 in the 3/4 pvc now. I tested it and it goes smooth through with no lube. I found 2 guy at H-depot that say 1 3 wire line and 2 others that still say 2 12/2 lines.

 

[brandonsdad02]

That guy doesn't know what he is talkIng about. 12/3 is fine. The neutral thing is a load of crap. The neutral carries the same load no matter what. If it was bad the national electric code wouldn't approve of it. EVERYTHING that is wired for 220V has one neutral. Your bare copper wire is a neutral as well. They both connect to the same place in the Panel.

 

[brandonsdad02]

Dont use 14/3. I would use 12/3. When doing long distances, there is always voltage drop. The lOnger the wire is, the more resistance there is and resistance means voltage drop. That's why sometimes we have to upsize the wires to make up for the resistance from the voltage drop.

 

[brandonsdad02]

Another thing to prove my point. When the power comes into your house it is 2 hots, a neutral and a ground. If this guy is worried about the neutral carrying a extra load, then each house would have a neutral going back to the sub station where the high voltage lines cOme in. On the lines going to the sub station, there are only 4 wires. 2 power wires, a neutral and a ground.

That guy doesn't know what he is talking about

 

[waynefrcan]

http://www.homedepot...-csa-75m/908335

Multiple conductors for interior use, not outside?

Whats that 600watt max rating? My 2 main pumps alone are 900 watts.

 

[brandonsdad02]

Says at the very top used for outside lamps, pumps and ect. Can be direct burial.

 

[brandonsdad02]

600 volts. Not watts

 

[waynefrcan]

Says at the very top used for outside lamps, pumps and ect. Can be direct burial.

That is just saying that this NMWU type wire is underground rated. Further down it says for multiple conductor [12/3] applications are for interior, not exterior.

 

[waynefrcan]

600 volts. Not watts

Right.

 

[markd]

That guy doesn't know what he is talkIng about. 12/3 is fine. The neutral thing is a load of crap. The neutral carries the same load no matter what. If it was bad the national electric code wouldn't approve of it. EVERYTHING that is wired for 220V has one neutral. Your bare copper wire is a neutral as well. They both connect to the same place in the Panel.

This is not really accurate. The only time you share a neutral is if you are running both phases on the hots- IE using a dual breaker. If you run 12-3 and hook up the red and black wires to the same phase, you will indeed overload your neutral.

Your bare copper wire is not another neutral, it is a safety ground.

Pretty good explanation of split wiring here-

http://inspectapedia.com/electric/multiwir.htm

Romex is not typically rated to be put in conduit. I think it is because the insulation cannot withstand the temperatures that may be reached in a sealed environment, but I'm not sure about that one. Same reason there are fill ratios for given conduit sizes.

I'm an electrical engineer, not an electrician.... the codes are complicated, and sometimes counter-intuitive, but usually they are for a good reason- that being it is easy to kill someone with electricity. If you are not sure of what you are doing, seek professional help.

 

[waynefrcan]

Yes I'm sure that's what brandon was thinking of, a 2 pole breaker. I know now since yesturday [post #64] that the people against 12/3 must not know about dual pole breaker etc. The one needed has a tie bar.

Some info from the net:

However a 3-wire circuit (black, red, white and the ground) cable can be used for feeding two circuits that will share the neutral and ground wire.

This 2 circuit multi-wire configuration requires that the black and red hots be attached to a two-pole circuit breaker that has a tie-bar so that these two circuits are not fed from the same buss in the panel
This will ensure that the neutral wire load will be balanced and not become overloaded under normal circumstances. The voltage reading from black to red will be 240 volts because they are attached one to the two separate busses or phases, but the voltage reading from black to white/neutral or ground will be 120 volts and the same for the reading for the red wire to white/neutral or ground.

I went to the breaker panel and tested it. Sure enough exactly what he stated is true. No neutral overload.

The H-depot guy that said stay away from the 12/3 over loading the neutral, and to stuff 2 fat underground rated 12/2 wires into 3/4 pvc was an electrical engineer. Now they are taking back the damaged 12/2 wire.

 

[waynefrcan]

My question now is, aren't all 2 pole breakers the same? 2 pole means linked together? How to tell if it is the correct one?

 

[brandonsdad02]

They Will either be connected by a metal tab or a small metal bar going through the center hole of the two pole breaker. Yes they are linked together and as long as you go with a two pole breaker it'll be done right. All of the double pole breakers I have seen are one unit not two separate breakers