Paging Billy from Pro-Scapes...

Discussion in 'Landscape Lighting' started by GreenLight, Dec 12, 2008.

  1. GreenLight

    GreenLight LawnSite Senior Member
    Posts: 462

    Hey Billy I am pretty new to the forums and I have really gone through a lot of posts just checking my philosophies with others and I came across a discussion of yours from a few days ago with Mike from IslandLeds. You struck a chord with me when you mentioned Hybrid T's. I did a job a few months ago where I was budgeted for only one transformer (600 watts) but as it turned out I was going to end up doing runs of 200 and 150 feet each with around 240 watts of lights on them. This was the first time I felt the rocketing downside of voltage drop (only done about 10 lighting jobs so far.) Even though a third run could have been used to possibly get more wattage, it was almost pointless because every run ran so far away from the transformer that I was going to spend a lot more money for all the cabling, conduit, labor etc...Suffice to say, I ended up doing a run of 100 ft 8 gauge wire from one circuit, T'd off in two directions with 10 gauge wire (necessary to get my voltage drop back in check) and ran these 2 10 gauge wire an additional 50 feet while doing T chains from my fixtures to the 10 gauge. On the other circuit, I did an 80 foot run of 8 gauge and basically followed the same example as the first....

    The only snag I ran into on the 2nd circuit was I was at about 12.6 volts on my first T'd in set of lights to the 10 gauge. I was in the 15 volt hot of the transformer, but I couldn't drop down because every other light chain on the this run tied in perfectly between 11-12 volts. Long story short, I wanted to share with you I honestly didn't know the name of the type of wiring structure I had completed. After hearing you talk about Hybrid T wiring I realized that is precisely what I had done...

    You seem pretty skilled in this stuff so I have a simple question after being so long winded ( but I wanted to share this stuff with you because you seem quite knowledgable and I could show you a mach up drawing of what I did if it's easier), My ultimate solution for being overvolted on that one lateral line that came off the hybrid home run was to simply over wire the lateral line by 15 feet and then coiled it up and buried it next to my junctions. This overwiring of 15 feet got me down from 12. 6 to 11.9...Theoretically it worked like a charm and didn't really disturb any other lights on the circuits hybrid homerun, voltage on every other chain of lights on the circuit basically stayed the same. Was there any easier way to lower my voltage on that single lateral run without messing with the homerun? Also, is there anything wrong with coiling 15 feet of wire in a clean fashion and burying it?
    ***Also, anyone else who feels like commenting, feel free...Im not trying to alienate anyone, just from reading a previous post, I knew Billy had experience with this situation.****
     
  2. NightLightingFX

    NightLightingFX LawnSite Senior Member
    Posts: 581

    I personally like Uniques' transformers. They have voltage taps that range from 12-18v then 20V & 22V. And with a fully loaded transformer, they have minimal voltage drop - I rarely if ever have to re-adjust my voltage for a system after everything is installed. It is pushing it but you can go out to 200 ft for a homerun with their 22v tap on 12 ga. (If I knew I had to go that far for a run I would probably use 10 ga.)

    Sometimes I will get caught between the 18v & 20v tap. In that case I will go with the higher tap and add some wire (bury the extra wire) to create voltage drop to get the right voltage to my hub.

    If you want to create more resistance for more voltage drop with less wire use a different gage wire. Just be aware of what your draw is. With 12 ga. don't push more than 16amps, 14 ga. - 12 amps, 16 ga. - 10 amps

    Other voltage regulating techniques. Use a voltage enhancer to get a boost of voltage in a homerun. Use a voltage regulator for each fixture - If the voltage is too high at a fixture it will drop down the voltage to ~11.5 volts
    ~Ned
     
  3. NightLightingFX

    NightLightingFX LawnSite Senior Member
    Posts: 581

    I personally like Uniques' transformers. They have voltage taps that range from 12-18v then 20V & 22V. And with a fully loaded transformer, they have minimal voltage drop - I rarely if ever have to re-adjust my voltage for a system after everything is installed. It is pushing it but you can go out to 200 ft for a homerun with their 22v tap on 12 ga. (If I knew I had to go that far for a run I would probably use 10 ga.)

    Sometimes I will get caught between the 18v & 20v tap. In that case I will go with the higher tap and add some wire (bury the extra wire) to create voltage drop to get the right voltage to my hub.

    If you want to create more resistance for more voltage drop with less wire use a different gage wire. Just be aware of what your draw is. With 12 ga. don't push more than 16amps, 14 ga. - 12 amps, 16 ga. - 10 amps

    Other voltage regulating techniques: Use a voltage enhancer to get a boost of voltage in a homerun. Use a voltage regulator for each fixture - If the voltage is too high at a fixture it will drop down the voltage to ~11.5 volts
    ~Ned
     
  4. Pro-Scapes

    Pro-Scapes LawnSite Platinum Member
    Posts: 4,181

    I dont know if its just late or that was really hard to follow. What I did was make the T just about in between 2 hubs and fed both hubs from the T. This is very similar to how unique talks about wiring the 24v intellisystem but judging from the 3 years ago I first did it to the debut of the 24v system Joey has some explaining to do lol. Maybe Im first this time but i am pretty sure someone has tried or done this before.

    To answer your question I would have probably ran seperate lines to each hub in your situation. This would make it easier to add lights later or up wattages. When I do this method it is usually for a long narrow bed or a long walkway.

    When you do a T try to think of a scale. You want as close as possible to a balance in your loads and lenghts. Granted it does not have to be spot on.

    Lets clarify what I consider a hybrid T. I would place my 2 hubs as needed. I would then lay a wire connecting these 2 hubs.

    Finally I would bring a heavy ga wire in and splice it somewhere around the middle of the wire connecting the 2 hubs. You need to still follow the rules that pertain to v drop of course and add in the load from both hubs along with the lenght of wire from the trans to the T and 1 leg of the T. If this sounds confusing you probably are better off running a single wire to each hub.

    Lets place it in a scenario. If you had a really long L shaped walkway and you have 6 pathlights at 20w each. It is way to long for a traditional hub but you could easily do it with 2 hubs. Since 120w of lamp load is well within the uses of 12 and 10ga wire it would be a good canidate for this method. With what you paid for the 8ga wire I probably would have opted to run a 10ga to each hub instead. I wont say I have never added wire to bring voltage in check but I no longer see the value in it. If I need to add wire to lower my voltage there was probably a better way to do it even if it costs a bit more.

    Hope this helps.
     
  5. Mike M

    Mike M LawnSite Bronze Member
    from usa
    Posts: 1,941

    every other light chain on the this run tied in perfectly between 11-12 volts.

    You had a lot to say, but this stood out to me. If it was me, I'd drop them one volt.

    Also, I'm not sure if you have picked one up yet, but you may want to get an amp probe. I think the 8 gauge took care of the amps, but it is standard practice to know how many amps your wires (and transformers) are rated for (or they may burn).

    Even though you are following the guidelines of 240 watts for that 300 watt transformer, you can still overload it with long runs at high taps. Especially when the client replaces your 20's with Lowe's 50 watt specials.

    The 24v system can handle these multi-step t's because the amp dynamics are improved significantly.
     
  6. Pro-Scapes

    Pro-Scapes LawnSite Platinum Member
    Posts: 4,181

    I still think 8ga for a somewhat short run was overkill. More versitile and better control with multiple runs of 10 in his situation.

    I use 11.5 to 15v transformers and have gone a real long way.

    By the time you put in alot of 8ga for long runs make sure your not better off to install line voltage in the area and add another transformer.
     
  7. Mike M

    Mike M LawnSite Bronze Member
    from usa
    Posts: 1,941

    I agree with Billy. I've even gotten away from a lot of #10. I think I was over-compensating to be safe when I was first installing. It's funny when you run into 8 in the field, it looks like jumper cables. I have yet to see where it was used that it was the best solution.

    Anyways, with the amp probe and the slide/chart voltage thing that Unique has, I have been planing wires and transformers more efficiently. I even use my measuring wheel or pace out all the runs during my demo's. It takes the guesswork out, plus it makes my estimates more accurate.
     
  8. JoeyD

    JoeyD LawnSite Silver Member
    Posts: 2,933

  9. GreenLight

    GreenLight LawnSite Senior Member
    Posts: 462

    Ned - Thanks for the advice on the voltage regulator for the fixture and voltage enhancer for the home run...Also the 24 volt transformer is something I have looked into ...Your advice is noted by me for future installs.

    Mike - Thanks a lot. The amps part on these long runs made me a bit skiddish as you mentioned...The 8 gauge home run just made me feel better at the time and in retrospect I probably rookie moved it a bit there. Honest question, because I am not fully aware, but why would I want to drop one volt at the transformer if my light chains are between 11-12 volts (never exceeding 12 at any point)? Wouldn't I be undervolted a bit on runs where I was getting right at 11 if I dropped down a volt it would be put me at 10.1 or so? I do grasp what you are saying about the added wattage accumulated by the long runs and appreciate you noting that as it is a valid point. As far as the homeowner replacing bulbs, not to be a smartass (just lack of my knowledge), but wouldn't that apply to just about every job? Even if it were a short run of (7) 20 watt lights - 140 watts from fixtures only, but if they replaced those 7 lights with 50 watt bulbs (350 watts fixtures only) they are going to flip the breaker anyway right? Either way, that's there mistake and im getting a service call out of the deal I would imagine. Am I on the same page with you there?

    Billy - Appreciate all of your advice on this very much. I personally have never used HUBS, but am looking into it now. Even though I am pretty green and my long winded explanation was really murky, I think I am close to what you are describing above, simply without the hubs. I attached a simple replication of one of the 2 runs below....A few questions if you don't mind.

    1) When using a hub, isn't the standard wiring from the hub to each fixture an individual run of 25 feet each? If so, is there generally a static figure of voltage drop from the hub to the fixture?

    2) I can cut hub leads to fixtures that are close to the hub correct?

    3) What gauge is the hubs lead wire to the fixture or is this interchangable?


    Last thing, I attached a simple replication of one of the 2 runs below just so it would make more sense, as my first post was pretty confusing.

    lightlayout.jpg
     
  10. Mike M

    Mike M LawnSite Bronze Member
    from usa
    Posts: 1,941

    Okay.

    First, why not put some info about your business and a contact number or website? You can do this in your profile.

    Second, Joey works for Unique, and maybe he can hook you up with an overview of the hub system. Unique has a book that will address all of your questions and it is my favorite book by far on the subject of lighting, both from a tech perspective and from a design perspective.

    Manu's like Unique and Cast provide us with 25' leads already attached. Cast also has a nice little guidebook for technical tips and wiring configurations. Many of us using the hub method use brown irrigation hubs (5 bucks?) to put our connections in. You can just use a T for two fixtures, but it's nice to attach an extra pigtail in the hub for future add-ons and taking meter readings, servicing, etc.

    I believe it is cheaper to use two #10's than one #8. In fact, you should be able to use mostly 12 gauge, especially if using transformers with taps above 15v.

    To answer some more q's: you can bury the slack lead wire at the fixture, which also makes for convenient moving of the fixture as plants grow and landscapes change. You can also cut it without changing the volts much, but why bother? An advantage of the hub system is that each hub is fed by an independent home run, and can easily be adjusted for optimal voltage with the taps, plus, each fixture gets the same voltage. Using separate home runs with the hub method is an easy way to "divide and conquer" your system, making installation a snap as well as managing future changes, add-ons, and servicing.

    You can be as creative as you want with the wiring, take short cuts, etc., as long as you are comfortable with your voltage meter and amp probe, and you know the limits for amps on the wires and transformers. It sounds tricky, but it is spelled out clearly in the manuals I mentioned, and as you do it it becomes much easier.

    You'll see there are many excellent ways to do wiring and connections.

    You should also know that the big thing now is how we are liberating ourselves from 12v voltage drop issues and narrow halogen cycles, as we are installing the new LED's, 24v systems, etc.

    Mike
     

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