1. Missed the live Ask the Expert event?
    Not to worry. Check out the archived thread of the Q&A with Ken Hutcheson, President of U.S. Lawns, and the LawnSite community in the Franchising forum .

    Dismiss Notice

Waterproof splices

Discussion in 'Landscape Lighting' started by bcg, Apr 21, 2011.

  1. bcg

    bcg LawnSite Bronze Member
    from Tx
    Posts: 1,835

    Being an irrigator before getting into lighting, I naturally used the King connectors on my lighting work as I'd had such great success with them in irrigation. Lately, I'm seeing for myself (and I apologize to those who will rightly say "I told you so") that they have some issues with water intrusion. The picture is of a connection that I repaired (not my install) this week on a system that used the tan/white King connectors and was done pretty much the way I would have done it. This is about 6" into the wire, which was as far back as I could get with the slack I had, and it's still a little green after only a few years in the ground. From what I'm told, the grease in the King connectors melts from the wire heat, which is much more in LVL than irrigation, allowing it to run out of the connector and water to take it's place, which makes perfect sense now that I've heard it.

    So, what I'm thinking of doing is continuing to use the wire nuts but to put an adhesive lined heat shrink tube over the top of the wire nut and the wire. I like the ease of installation that the wire nuts allow and believe that the extra protection of the heat shrink will keep the grease where it's supposed to be. I may also be switching to a nut filled with a silicone instead of whatever the King connectors use. This is the heat shrink I'm considering - http://www.shop3m.com/80610787808.html.

    What is everyone else doing to make sure their connections are waterproof?

    I've also looked at crimp and heat shrink connections, like Lighting Shrink and another 3M product and they're really not any more expensive that what I'm considering but I like being able to just twist and go and having the flexibility to easily redo a splice during installation.

  2. klkanders

    klkanders LawnSite Senior Member
    from Midwest
    Posts: 848

    This is always a great topic. I have also come upon old connections of this type many over 10 years old. My findings are mixed. When taking them apart some wire has terrible corrosion and wicking while others look close to new. I have never been a fan of just grease filled wire nuts. (sorry David)
    I use a combination of King Ace connectors http://www.kinginnovation.com/products/irrigation-products/ace-connector/ and North Star Industries DBR's with the copper crimps. I have also used the connectors from Lighting Shrink. All good products.
    I like, when possible, to install all my fixtures, wire, connections and leave them uncovered for the first night. This lets me take all readings with my meter and make any adjustments as needed that night when viewing the property with my clients. The next day the dbr's are installed over the crimped connections, the shrink tubing pulled over the Ace Barrels, heated and wire buried.
  3. rlitman

    rlitman LawnSite Bronze Member
    Posts: 1,552

    Silicone filled wire nuts marked DB (for direct burial) are kind of ok.
    Adhesive lined heat shrink tube only works if you can get it to bond to the circumference of the wire (must have round wire with no ribs, so it won't work well on split zip-cord type wire).
    I've wrapped in Scotch 88 electrical tape, and coated with 3M Scotchkote liquid electrical coating with some success. That stuff kind of melts the vinyl tape to itself, as well as builds up like a liquid electrical tape. I've had the most success with using that OVER DB wire nuts, BUT you must be careful when using the DB wire nuts, because if any of the silicone gets on the wire jacket (like if you have to remove them), then you'll never get anything to stick.
  4. emby

    emby LawnSite Senior Member
    from Ontario
    Posts: 380


    I solder all my connections with a solder pot. Once soldered I use Ideal's silicone filled marretts http://www.idealindustries.ca/products/wire_termination/twist-on/underground.php and then I tape that with 3m's super 33.
    For any discrete connections such as on a gazebo etc. I have had great success with the ace connector.
    Knock on wood but I have yet to find any failed connections or wicking. The silicone in the Ideal's are clear not white as you may find in the Kings.
    Hope this helps.

  5. S&MLL

    S&MLL LawnSite Senior Member
    Posts: 751

    King switched over 2 years ago to the clear sillicone. Much better then that white paste they were using.

    I might be crazy. But I still say there is something differnt from the ones I buy to the ones they sell at lowes. The only time Ive ever had a failure was on a blue/red? ...... I dont know lowes colors for the KING wire nuts. What does everyone else buy colorwise. I get black/white. Black/gray. Black/blue.
  6. rlitman

    rlitman LawnSite Bronze Member
    Posts: 1,552

    Yup, those are a quality Direct Burial connector.

    The scotch 33 is very similar to the 88. The 88 is just a little bit softer in cold weather, and a tad bit thicker. Both are an excellent tape, with some of the best adhesive available, which don't unravel. No other tapes compare (except the scotch 35, which is the 33 in colors other than black).

    Still, I prefer to go over that stuff with Scotchkote when underground. It bonds layers of that tape into a single rubber mass, and completely seals the edges.

    In the days before direct burial connectors, I soldered all my underground connections. It kept continuity going even if water intruded, but if water did intrude, it would trip GFIs. Focus on a well sealed connection, and corrosion won't be a problem, so soldering is unnecessary.
  7. Lite4

    Lite4 LawnSite Gold Member
    Posts: 3,113

    Posted via Mobile Device
  8. Lite4

    Lite4 LawnSite Gold Member
    Posts: 3,113

    I used to crimp and heat shrink everything. For hubs and most direct burial connections, Northstar DBYs have worked very well for me. I am a stickler about crimping my connections so they never get loose and cause a heat issue and the quick installation of the grease cover keeps installation time down. They have a really sticky grease that will not wash out.

    For above ground connections I still crimp and heat shrink. I buy buchanan copper cimps at Any box store in boxes of 100. I buy my heat shrink tube in bulk and cut it to a usable size. I buy 3/8" tube for fixture connections and 5/8" for hub sized tube.

    Go to buyheatshrink.com
    I get the medium wall, adhesive lined tubing.
    Posted via Mobile Device
  9. bcg

    bcg LawnSite Bronze Member
    from Tx
    Posts: 1,835

    Thanks to everyone for your suggestions. I'm going to try many of them and then do some testing to see what works best. I'll let you guys know what I discover.
  10. Tomwilllight

    Tomwilllight LawnSite Senior Member
    Posts: 284

    Like rlitman, I use Scotchkote to seal my LV splices. But I dip each splice twice.

    First I dip the tightened (and tested with an honest yank) splice into Scotchkote, hold it under until the bubbles stop and the edges of the insulation are covered. Then I set the splice aside to harden. Once I've dipped all of my splices I comeback and tape them with good quality electrical tape and dip them again in the Scotchcote. The Scotchkote does a very good job of preventing any siphoning of water up and into the wire insulation.

    I learned this technique from Greg Yale and have NEVER had a splice so treated fail in the 12 years I've designed and installed landscape lighting.

    I use the Scotch wire nuts that have the flexible skirts because they allow me to pull the wire insulation into the wire nuts.

    It's relatively cheap and I like the way the Scotchcote decorates my hands and all of my work clothes.

    TIP: Store the open Scotchkote cans in ziplock bags for transport.

Share This Page