Running low voltage wire next to 220v wire

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  #1  
Old 06-30-14, 09:14 AM
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Running low voltage wire next to 220v wire

I'm planning on putting my low voltage transformer 600w close to my main home panel. Right now there is a conduit that has a 220v wire running through it to a back yard spa from my main panel. I want to run my low voltage wire through this same conduit and route it to the front yard for my landscape lights.

Will this be a problem running 12v wire(s) next to 220v wires?
 
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Old 06-30-14, 09:58 AM
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I want to run my low voltage wire through this same conduit
You cannot run the LV wiring through the same conduit as the 240v wiring.

You can run them in the same trench but in two different conduits.
 
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Old 06-30-14, 10:10 AM
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yes, that will be a problem.
 
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Old 06-30-14, 11:25 AM
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If this is for LV landscape lights, may times the transformer says to only be used in outdoor locations.
 
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Old 06-30-14, 01:21 PM
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This will be 100% outdoor locations including mounting of transformer
 
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Old 06-30-14, 01:24 PM
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Thanks for the reply. Can you tell me why that is? Reason I ask is I asked an electrician friend of mine and he stated that as long as it's just used for power and not code or command signals it would be fine.
 
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Old 06-30-14, 02:20 PM
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By NEC the insulation value of all wires must exceed the highest voltage in the conduit. Low voltage wiring insulation is generally rated for less than 240 volts and is class 2. Class 2 must not be run with class 2. The transformer may also be class 2..
 

Last edited by ray2047; 07-02-14 at 06:38 AM. Reason: Edited for accyracy.
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Old 07-01-14, 09:24 AM
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Then since this will be a short run, i.e. 3-4 feet can I up the gauge of wire for this portion and run the standard LV wiring for the remainder?
 
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Old 07-01-14, 11:54 AM
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Gauge is not relevant. Insulation and class rating is. You could use THWN of the same gauge but only if the transformer is class 1..
 

Last edited by ray2047; 07-02-14 at 06:39 AM. Reason: Misleading and inaccurate.
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Old 07-02-14, 06:04 AM
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From what I've seen, quality hook up wire is rated for 300 volts or 600 volts. I would think you need the temperature rating also. Technically your 240 volts is really 120 volts on each leg. I would not run speaker wire or coax cable since they are not voltage and temp rated.

Is not your ground a low voltage wire?

Of course you have to follow the NEC rules but why would low voltage make a difference?
 
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Old 07-02-14, 06:20 AM
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The "problem" as far as the NEC is concerned is with different "classes" of wiring. The 240 volt circuit is a "class 1" circuit and the low-voltage lighting (with the standard LV wiring) is a "class 2" circuit. You may NOT have both class 1 and class 2 circuits in the same conduit. Even if you substitute type THHN/THWN insulated conductors for the low voltage cable this would only be allowed if the power supply was also a class 1 listed unit. Some low voltage lighting transformers ARE so listed but most are class 2 listed.
 
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Old 07-02-14, 06:40 AM
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Posts have been edited. Thank you Furd.
 
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Old 07-02-14, 10:48 AM
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Furd is right, class rating superscedes the voltage rating of the conductor so you cant tap dance around it that way.

Besides being a direct violation to the NEC, Mixing the two in my opinion is sloppy esp. for garden lights.

How long do landscape lights last in the elements? 2 seasons before you would have to yank those wires out of the raceway for your new lights. They have no business in the same conduit as a 240 circuit.
 
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Old 07-03-14, 02:00 PM
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Engrish Prease

How long do landscape lights last in the elements? 2 seasons before you would have to yank those wires out of the raceway for your new lights. They have no business in the same conduit as a 240 circuit.

Lights in the elements?
Do you mean rain, heat, fog etc?

Wires out of the raceway?
 
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