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ChampionLS
04-07-2007, 06:13 PM
Hey guys,

I have a client in the south who wants to install our Paver/Deck Lighting System into a 300' long Boat Dock. The dock is 7' wide x 300' and made from Mahogany. Even though our system is water proof to IP68, they don't want to use the Power Tap Connector, or Direct Burial Wire Nuts. This means using conduit and a junction box at each fixture. The wire to each fixture is 18/2 SPT-1W

I have two questions :

1) Who makes a Cable Gland or Cord Grip that will accept a 18/2 flat wire, and adapt to standard 1/2 NPT

2) The Architect does not want to use a conventional transformer. Not even a stainless steel one. They want to hardwire a bullet proof one to the system, and control it with line voltage. Sounds like a candidate for a direct burial transformer, but preferably one that can be flange mounted or lag bolted to the dock/piling etc. There are may sources. Any ideas?

Thank you,

Anthony

NightScenes
04-07-2007, 08:21 PM
You can only use a transformer that is rated for pool and spa use when installing fixtures around water. I know that Unique and Acme make pool and spa transformers. These are hard wired transformers and must be GFCI protected.

I don't know what you are talking about, Cable Gland or Cord Grip? Why not use pvc conduit under the dock and use an electrical "T" at the connections?

ChampionLS
04-07-2007, 09:33 PM
Hi Paul,

I'll research those transformers. I'm aware of the isolated secondary for pond/spa use.

I do plan on using the PVC conduit and TEE, and I am looking for a reducer or gland (as it's called) that will adapt to flat, paralell wire. Most are usually for the round cord. It looks like a compression fitting for tubing like you would see on a brake line., but this has a rubber grommet and one with a rectangular hole. It needs to be for a small 18 gauge wire.

Thanks for your help.

Anthony

ChampionLS
04-07-2007, 09:36 PM
Heres what it looks like:

eskerlite
04-09-2007, 08:47 PM
Whats a bulletproof transformer and why not a stainless steel one with a fereday shield12-15v. I use ace connectors near all water. The conduit will look real bad.

seolatlanta
04-10-2007, 12:08 AM
Those only come in cord grip size for sj cord 16 ga or they come in a flatter model for 120 volt uf outdoor cable. Any of those sizes will be too big for 18 gauge wire.

At Home Depot if you go the the electrical area and look in the metal fitting area you might find them.I think they are called service disconnects but I cant remember-they are for watertight seals.

seolatlanta
04-10-2007, 12:11 AM
Also Unique also makes a great direct burial transformer-check it out at

www.uniquelighting.com

I have no idea what you are talking about with a bullet proof transformer!

ChampionLS
04-10-2007, 12:48 AM
The conduit will be under the dock, before the planking is installed- It's Carlton PVC Conduit. At each fixture will be a 2x4 box. I found a Cord Grip by Heyco thats laboratory grade, made for small Parallel cable. (Home Depot only carries residential stuff, but Heyco was helpful in assisting) A hole will be drilled through the box cover and a grip installed. The fixture wire will be threaded into the grip and a connection made inside. The contractor is going to use standard 12/2 circuit cable and connect with the Hadco LVC3. They omitted wire nuts to alleviate cutting/splicing. Theres a total of 42 - 4 watt lights on the circuit (168 watts total). One 300W transformer from Focus will do the trick and leave more room for additions later. I'll post some photos when the job is completed.

NightScenes
04-10-2007, 08:54 AM
Just remember that regular 12/2 romex is not approved for use in LV systems. It also is not the best conductor for this project. You will experience more voltage drop due to using a single conductor wire as opposed to stranded LV cable. This would most certainly require the use of a "loop" method.

Just my $.02

Pro-Scapes
04-10-2007, 11:11 AM
168w on a 12/2 wire is a no no anyways. Sure its rated for 180 max but its not a good idea. With your 4w lights and the lenght of the short leads multiple loops with LV cable would be alot better than 1 giant loop. Your light output would be that much more even anyways.

ChampionLS
04-11-2007, 05:22 AM
The wire would be standard 12/2 Underground Circuit Cable, not Romex. Another option if 168 watts is too much would be to use 10/3 and route 1/2 the current on one leg, 1/2 on the other. Alternating the double sided Hadco connector will allow connections to either circuit.

eskerlite
04-11-2007, 05:23 PM
You cannot daisy chain all those fixtures off two lines. You will need multiple lines to maintain 11.00-11.5v at all fixtures. Many runs for this application.Do the math for the fixture 300 ft away with 12-2.
Sean C.

ChampionLS
04-12-2007, 01:56 AM
I believe we are well within specs. Here are some facts from Ruud Lighting's spec sheets. :


One continuous cable coming back around to the transformer. One 300W transformer with 150W total load (75W per circuit). Recommended maximum cable loop is 650'.

Pro-Scapes
04-12-2007, 08:50 AM
I believe we are well within specs. Here are some facts from Ruud Lighting's spec sheets. :


One continuous cable coming back around to the transformer. One 300W transformer with 150W total load (75W per circuit). Recommended maximum cable loop is 650'.

This will not work right for you. 650ft of 12ga wire with an 85w (ok so your looking at 84 if you split em. would have about 13.75 voltage drop. Een if you looped it your going to have some serious voltage isues with your first fixture popping bulbs and your last one looking like a birthday candle. I say more than 1 trans... 1 at each end and then 2-3 runs per trans. Unless you got some kind of magic wire. I really dont think they will 1 look even enough 2 get the proper voltage ... just because some 3rd rate lighting company like Rudd says something is within "spec" doesnt mean we should do it.

Im bangin my head on the wall trying to correct a similar situation installed by a guy now. there is nearly 5v of difference across the system!

eskerlite
04-12-2007, 07:41 PM
You are talking about a 12-3 wire not 12-2. for some reason rudd thinks its ok to have one common and two hot wires made together. This wire is very heavy to handle and is a pain in the a$% to work with. Secondly any fixture with 4 watts is not going to light up anything but the inside of a Coke can. A minimum of 10 watt bi-pin or 921 wedge base lamped fixture brass or copper should be used NO ALUMINUM. They should be 8 feet apart on opposite sides of railing. You will need 8-2 to reach 300', 10-2 for 200 feet or less and 12-2 for 100 or less with real fixtures. I priced out a similar walk way from house to beach 300' and it was every 8 feet. 37 lights @ 16 watts ea., a 900 watt or 1000 watt transformer would have been used 12v-15v. A 600 would be 50 watts too small.$10,500.00 approx.You will also replace all of the hadco lvc3 splices you make prematurely because there is no worse way to connect wires especially near water.An ace connector is your best bet.
Sean C.

ChampionLS
04-12-2007, 11:59 PM
Wholly Moly. Pay attention here.

1) We are using 10/3 cable. The cable will be pulled through PVC conduit and a Carlton junction box will be at each fixtures location, approximately 7' apart. A weathertight fitting (IP68) will be on each light fixtures cable and threaded into the junction boxes cover. The Hadco connector is UL listed to 10 amps. The fixtures only draw .333 of an amp and are 4 watts. We are supplying the Evening Star flush mounted accent light as per this job specs. Our lighting system is cULus listed to IP68 and is completely waterproof. Installing the Connector in alternate fashion will tap into one of either two hot leads. My question was how many and where to mount the transformer, because the engineer on the project does not trust mounting any exposed transformer (regardless of manufacturers claims to weatherproof) outdoors. Thats for them to decide. We'll make sure to use several runs so theres minimal if any voltage drop. We've done this before on driveway installations, just not the conduit issue.

I'll keep you posted if something comes up. Thanks for the help Billy

I forgot to mention... there is no railings or exposed sides on this dock. Photos to come soon.

-Anthony

Pro-Scapes
04-15-2007, 03:35 PM
I dont think Sean is disputing the power handeling capabilities of the hadco quick connector but more of the reliability of it. Near water fixtures and splices are subject to a much more corrosive enviorment especially salt water. The hadco pierce connector is not as sealed as it could be and will eventually fail.

10/3 will be even worse to work with than the 12/3. It will be a nightmare in my opinion.

Anthony I really think this job requires more planning. You asked for help and when you got it you decided a different route. Do you think Rudd cares how long your lights will last on this project ? especially since your using your lights and not thiers.

Follow some of the recomendations and you will get better results and then charge accordingly.

niteliters
04-16-2007, 05:40 PM
champion, how many lv design/installs have you done. visited your website and saw no mention of this part of your business?

niteliters
04-16-2007, 05:51 PM
I'm looking at all this technical back and forth and I am struck by something. Who decided on paver deck lights...whas that your design choice after seeing this deck and the surrounding area, or was it your customers? All this technical info exchange is very important, however the best working system technically installed to perfection won't matter one bit if it looks like hell. I only bring this point up because paver lights that I know about direct light up to space and can cause glare not only for the person using the walkwat but annoying glare for those who live nearby. Which gets me back to my original question. Have you been to this area. Pictures of the walkway could be decieving...often times won't reveal whats going on in the space around him. Does he fly a plane and love runway lights? I am not asking that arrogantly, I had a pilot who wanted a runway light effect for his driveway just last week. Wife wasn't crazy about it :) talked him out of it so he would stay married. See the effect..not the source.

niteliters
04-16-2007, 05:54 PM
One more thing, if it is the cutomers choice, that doesn't always mean just go and do it if you know the end result will not be the true vision desired.

ChampionLS
04-16-2007, 06:43 PM
The Hadco connector will be installed inside a weatherproof conduit box at each fixture. The dock builder will be using regular underground circuit cable pulled through the pipe and connected inside that box. I believe they are using 10/3 divided into two circuits. I'm not sure how the overall layout will be, whether or not it's two circuits on one side and two on the other side. I will follow up this week. The dock is 6 feet over the water on a lagoon. The most splash that will occur will be from rain. It's a complete IP68 enclosure.

The Hadco connector will only work with 12/2 or 10/3 If something else were to be used.. say 8/2, then wire nuts only will have to do. Cost isnt really a factor, because this is a conventional wiring job. (unlike the wiring under a concrete patio where thats not permissible.)

Evening Star Lighting does not do installations, we are the manufacturer. I personally oversee local installations and teach seminars on the installations of our products. Everything we offer is UL listed and has met the requirements of UL as per our method of installation. This was a 3 year project that went under extensive review both laboratories in Research Triangle Park and Melville NY. The system works as outlined and is safe. Ruud lighting or any other lighting manufacturers have to follow the same guidelines as set forth in the UL1838 construction codes. If our system failed..even one of the 28 tests, I would not have our products on the market.

I appreciate the help with the transformer selection. I should have some final layouts this week.

How is this for waterproof? This fixture was on and underwater for 3 days at The EP Henry MAHTS Show. Who else can make this claim on a light that you can change in 10 seconds?.

niteliters
04-16-2007, 07:41 PM
this info is helpful to know. doesn't mention anything about this on your public bio you have submitted on this site. why not?

ChampionLS
04-16-2007, 08:46 PM
When I originally signed up to be a member, it was under my landscape design/build name. Evening Star Lighting is a partnership corporation, and a seperate business. We will probably be a sponsor in the near future. Stay tuned.

-Anthony