Marine Grade 12 Gauge Wiring for Low Voltage Lighting


  #1  
Old 06-11-20, 07:59 PM
S
Member
Thread Starter
Join Date: Jan 2013
Location: USA
Posts: 570
Received 0 Upvotes on 0 Posts
Marine Grade 12 Gauge Wiring for Low Voltage Lighting

I am hiring a contractor to install approx 45 low voltage fixtures at my house. The contractor is insisting on using Marine Grade 12 gauge wire ($1 per foot), silicone nuts, and 22 splice junction boxes for approx $1,000 in materials not including labor and fixtures. I can see the benefit of using all of this but wondering if this is overboard given the $1,000 price tag.
 
  #2  
Old 06-12-20, 04:44 AM
Geochurchi's Avatar
Member
Join Date: Nov 2012
Posts: 4,960
Received 158 Upvotes on 144 Posts
Hi, I canít remember ever seeing anything in the NEC about marine cable, unless you are installing the lights under seawater then I would say itís over kill , it may not even be rated for underground installation.
Geo
 
  #3  
Old 06-12-20, 05:07 AM
P
Group Moderator
Join Date: Mar 2003
Location: NC, USA
Posts: 25,944
Received 1,759 Upvotes on 1,572 Posts
I would not go to the expense of marine cable. I would use regular 12 ga NM (Romex) and regular wire nuts. The wire will have the same low resistance since it's 12 ga and the wire & nuts are much cheaper. The only downside I can think of is the rigid NM wire could be more difficult to work with depending on where it needs to be run. If you go this route I would make up some labels to put on each end of a wiring run to denote that it is low voltage.
 
  #4  
Old 06-12-20, 06:53 AM
D
Member
Join Date: Jan 2019
Location: Southern Arizona
Posts: 139
Received 9 Upvotes on 8 Posts
I would not use ROMEX underground when there is UF cable that is rated to be underground.
The biggest difference in LV cable and romex is LV is stranded and romex is solid wire. Stranded is what all of the LV fixtures I have installed were set up for. Check your fixtures for compatibility.

All of the marine wire I have seen is single conductor so maybe I need to get out more. I would not use single conductors unless they are in conduit. Again more complicated that needed IMO.
All of the LV lights I have installed were done in strings from the transformer, no splices out in the field. Think star, transformer in the center and the strings work out to from there.
I would shy away from anyone who is splicing underground. Yes it can be done. There is equipment made for it.
Seems like a complication that can be avoided.
 
  #5  
Old 06-12-20, 06:55 AM
Geochurchi's Avatar
Member
Join Date: Nov 2012
Posts: 4,960
Received 158 Upvotes on 144 Posts
Hi, NM is by no means direct burial, one Mfg. of marine cable I contacted said it was DOT and CG approved but doubted it could be used for direct burial, donít waste the money, I would get a price from another contractor, using silicone filled wire nuts is the only thing that makes sense, are these lights in a row or scattered all over, why so many junction boxes? what type of fixture are you using? Post a pic.
Geo
 
  #6  
Old 06-12-20, 07:10 AM
P
Group Moderator
Join Date: Mar 2003
Location: NC, USA
Posts: 25,944
Received 1,759 Upvotes on 1,572 Posts
Sorry, I forgot that low voltage lighting was probably being installed outside.
 
  #7  
Old 06-12-20, 08:03 AM
S
Member
Thread Starter
Join Date: Jan 2013
Location: USA
Posts: 570
Received 0 Upvotes on 0 Posts
Approx 20 lights in the front yard with half right against the house and the other 10' away highlighting some trees. 2 will be 50' away at the front of the yard to highlight a treet.

Approx 25 lights in the backyard all over the place from path lights in seating area to spot/path highlighting rocks around the pool to 50-100' away to highlight 4-5 trees. It's a much bigger project.

Correction: 14 "at most" metal top splice boxes per contractor.

I am going with Volt given the price point and lifetime guarantee. They offer a direct burial cable too which is ($185 vs. $500). The project will be nearly $7000 so I am OK with spending the monies if it makes sense.

https://www.voltlighting.com/low-vol...VAC-CAB-12-500

Debating these 2 spotlights:
https://www.voltlighting.com/landsca...p/VAL-2000-BBZ
https://www.voltlighting.com/landsca...VAL-2003-4-BBZ
 
  #8  
Old 06-12-20, 01:22 PM
Geochurchi's Avatar
Member
Join Date: Nov 2012
Posts: 4,960
Received 158 Upvotes on 144 Posts
Hi, nice looking fixtures, I might consider using some of these termination hubs maybe better than junction boxes and splices.
https://www.voltlighting.com/integrated-hub-system/c/92
Geo
 
  #9  
Old 06-12-20, 02:45 PM
S
Member
Thread Starter
Join Date: Jan 2013
Location: USA
Posts: 570
Received 0 Upvotes on 0 Posts
They are solid brass and spot lights range from under $30 to $75 with lifetime guarantee. It's hard to justify the $150-$250 per fixture such as Unique/Cast. It's been a good learning experience too.
 
  #10  
Old 06-12-20, 08:35 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 62,035
Received 3,415 Upvotes on 3,063 Posts
That Volt cable is priced good.
I use mostly Southwire 12-2 and it's right around $200 per 500'.

Most marine grade two wire cable I'm familiar with is white.
 
  #11  
Old 06-12-20, 08:41 PM
S
Member
Thread Starter
Join Date: Jan 2013
Location: USA
Posts: 570
Received 0 Upvotes on 0 Posts
It sounds like marine grade wire is overkill.
 
  #12  
Old 06-13-20, 06:55 AM
Geochurchi's Avatar
Member
Join Date: Nov 2012
Posts: 4,960
Received 158 Upvotes on 144 Posts
Hi, With the type of layout you are proposing check out this link for splice points.
https://www.voltlighting.com/landsca...tors-hubs/c/37
IMO better option than using waterproof wire nuts.
Geo
 
  #13  
Old 06-13-20, 08:28 PM
S
Member
Thread Starter
Join Date: Jan 2013
Location: USA
Posts: 570
Received 0 Upvotes on 0 Posts
The design currently has 14 or so splice junction boxes but I am unsure the specific one. Contractor said also another 150 or so silicone filled wire nuts. Does that not sound right?
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: