Landscape lighting

[Markmgr]

During a recent tour of a property with an electrician we noticed that the power supply cord to a lighting transformer and the low volt line were going into the same junction box. We took a look to find both line volt and low low lines were comingled in the box and in the condiuts. We opened up another box to find line volt and low volt lines leaving the same box to fixtures near by. Is it acceptable by NEC to have line and low volt circuits in the same jboxes and conduits? I have as many people saying yes as no.

 

[k2electric]

I would GFIC protect it, if you dont plan on seperating the low and line voltage wires in the jboxs...

On that same note I am not sure how come they are even in the same box unless there is a transformer in that box as well. Can you be a little more specific as to whats in those jboxs.

 

[George Stolz]

I would recommend asking a qualified electrician to look it over.

 

[petersonra]

I would GFIC protect it, if you dont plan on seperating the low and line voltage wires in the jboxs...

How would that change whether it meets code or not, as far as the low and line voltage wires being commingled?

I would suggest a quick look at 725.26(B)(1).

 

[kingpb]

If the low voltage cable insulation is rated for the maximum voltage that can be achieved by the circuits then it doesn't matter if they are run together. If they are sensitive electronics, instrument or control circuits, then some separation may be required due to noise. Landscape lighting should not be affected. IMO 725 does not apply.

 

[tom baker]

IMO 725 does not apply.

Can you state a code rule to that effect?
Is this an Art 411 system?

"If the low voltage cable insulation is rated for the maximum voltage that can be achieved by the circuits then it doesn't matter if they are run together."
This is one of the most misunderstood topics in the NEC
Read section 90.3
Read 300.3(C)(1) and its FPN
The assumption is that you understand the relationship of Art 725 to the rest of the NEC.
Also I find it interesting to note that what we call the "low voltage articles'
411
720
725
Don't have low voltage in the title at all.
When we use the term low voltage it means nothing.

 

[kingpb]

Tom,

Low voltage according to ANSI C84.1 is anything 1000V and below.

Your references all make sense, but it still means they can be run together provided the insulation level of the cable is sufficient.

Article 411 certainly applies, but if 411 applies then 720 does not. If the installation is in accordance with Article 300, then it would be a stretch to say 725 applies or requires anything different, because 725 refers you back to 300 anyway.

 

[tom baker]

725 does not always refer back to Art 300. Take a look at the FPN to 300.3(C)(1).
725.55(A) does not permit limited energy in the same enclosure, box or raceway regardless of the insulation rating.

 

[Pierre C Belarge]

Most likely the source for the "low voltage" lighting is a Class 2 source. Class 2 wiring cannot occupy the same enclosures, etc... unless you follow 725.55.

It does not matter if the insulation type is the same. 300.3(C)(1) does not apply to Class 2 sources, see the FPN and its reference to Section 725.55(A).

 

[curt swartz]

I have never seen a Class 2 landscape lighting transformer. I believe the maximum current of a class 2 source is 5 amps at 12 volts which would be 60 VA. This would be useless for most landscape lighting applications. Most landscaping transformers would be class 1.

 

[kingpb]

In searching the internet I was able to find only 1 Class 2 landscape lighting transformer, and it was specifically lableled as such.

As far as the FPN's, they are not required to be followed by the NEC.

 

[Markmgr]

Markmgr

Markmgr

I'm still confused, I get as many okays as not okays. I think the NEC should draft a section for landscape lighting. It sure will be confusing to work on a system set up like this. From a craftsman point of view I think it sucks.:-?

 

[tom baker]

And Class 1 is wired with a chapter 3 wiring method