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johnquest
07-09-2007, 12:14 PM
Question about the Hub method. Cast recommends one fixture per lead back to the hub at no more than 25ft of 16 gauge wire. I'm in a situation where I need 2 fuxtures at 20W each on one lead back to the hub. Should I up the gauge of the lead wire from 16 to maybe 12 or 14. The total lead length will need to be about 40 feet. I'll have two other leads with a single fixture each, which should be OK and is within Cast specs for leads and single fixtures. I have a single run from the transformer at 35 feet of 12 gauge to the hub and I'm using a Vista 300W MT transformer. Intend to add to it considerably in the future.

Thanks, all

John

Pro-Scapes
07-09-2007, 06:24 PM
Question about the Hub method. Cast recommends one fixture per lead back to the hub at no more than 25ft of 16 gauge wire. I'm in a situation where I need 2 fuxtures at 20W each on one lead back to the hub. Should I up the gauge of the lead wire from 16 to maybe 12 or 14. The total lead length will need to be about 40 feet. Are you saying you want to daisey chain one off the other when one is attached to the hub and the far light is attached to the first light ? I would rather add a longer lead to the 2nd light in a 12ga wire just because what happens if omeone pops a higher wattage bulb in the future.



I'll have two other leads with a single fixture each, which should be OK and is within Cast specs for leads and single fixtures. I have a single run from the transformer at 35 feet of 12 gauge to the hub and I'm using a Vista 300W MT transformer. Intend to add to it considerably in the future.Add considerably to a 300w trans ? A 300 w trans will run 12 lights at 20w.. I dont see room for considerable expansion here. How many lights are you putting in now ? How many planned for future ? consider 600w ????

Thanks, all

John

johnquest
07-09-2007, 06:58 PM
I thought this might be what I should do. Just run a separate longer lead in 12 ga to the more distant fixture. I'm putting in 5 path/area lights (SPJ10-03's) at 18W apiece but will be upgrading the bulbs to 20W. I'm going with a 300W transformer because my house/ yard is small and to light it well will work fine with the 300W. I can still create another run and hub for 5-6 more fixtures. Adding more isn't necessary.

The way I understand it is that I can have muliple runs even with the single circuit 300W transformer, as long as I don't exceed 25 amps on the common tap. Each of the taps (11-15V) will take up to 4 12ga connections. How does a guy get 4 runs of any significance out of a 300W transformer? At any rate I have the flexibility I need.

John

klkanders
07-09-2007, 09:17 PM
John,
To keep it simple I would put another hub out there where its needed. It is certainly ok to have just 1,2 or 3 fixtures off a hub. If you need to add another home run wire so be it.

INTEGRA Bespoke Lighting
07-09-2007, 10:43 PM
Personally, I think the HUB method of wiring is totally wrong and boarders on un-safe and illegal. I would never use this method for wiring a professionally installed LV lighting system. Do it right, learn your voltage drop formulae, over build it for the future.

Have a great day.

Pro-Scapes
07-09-2007, 11:14 PM
I do like the hub in alot of situations. I dont see how it would be illegal in anyways.. maybe north of the border ? As I become more and more profeciant I do find myself lending to other methods of wiring and also creating my own. Properties vary so much its often hard to use any one technique without banging your head on the wall.

Sometimes I feel the hub is more like the fool proof way to wire things. Its hard for any monkey with a volt meter and calculator to mess it up. I do appreciate the evenvoltage it provides us tho.

klkanders
07-10-2007, 12:45 AM
Welcome James!
I agree wiring can be done un-safe but does all hub wiring have to fall under that heading? I started out using the daisy chain, T, and loop methods always keeping in mind voltage drop, amps, etc.. Lately, where design allows it, I have also been using the hub method for some of the same reasons Billy mentioned but still checking the volts, amps as needed.

I am constantly on the lookout for a better, cost effective and safer way to wire my systems as I believe there may be no right or wrong method for any given job.

I look forward to reading more of your posts and learning as much as I can from your years of experience! Take Care!

Eden Lights
07-10-2007, 12:54 AM
I like the T method when lighting things that don't grow, move, or change in anyway. I like the hub method or lolli-pops on things that grow, change, and move.

steveparrott
07-10-2007, 08:30 AM
Personally, I think the HUB method of wiring is totally wrong and boarders on un-safe and illegal. I would never use this method for wiring a professionally installed LV lighting system. Do it right, learn your voltage drop formulae, over build it for the future.

James, would you care to explain what your thinking is behind your statements?

NightScenes
07-10-2007, 08:57 AM
Question about the Hub method. Cast recommends one fixture per lead back to the hub at no more than 25ft of 16 gauge wire. I'm in a situation where I need 2 fuxtures at 20W each on one lead back to the hub. Should I up the gauge of the lead wire from 16 to maybe 12 or 14. The total lead length will need to be about 40 feet. I'll have two other leads with a single fixture each, which should be OK and is within Cast specs for leads and single fixtures. I have a single run from the transformer at 35 feet of 12 gauge to the hub and I'm using a Vista 300W MT transformer. Intend to add to it considerably in the future.

Thanks, all

John

Hello John, the best way to handle this situation is to use and additional home run for the 2 fixtures at the end. I know that it might seem like a waste of wire but after many years of doing this I can say that you won't regret it. This will give you better voltage distribution and flexibility.

I also agree with Billy, you will regret using a 300 watt transformer within a couple of years. I have yet to have a client that didn't add to their minimal system within a couple of years. Then your adding another transformer, timer, photo control and maybe even an outlet.

Anyway, good luck with your project.

johnquest
07-10-2007, 10:25 AM
I imagine going up to a 600W transformer I could outgrow that as well. Less is more in my opinion, for fixtures at least, and light amount. This seems to be the overall opinion in the design texts I've read and opinion I have from the overlit properties I've seen. I have a tree that has some more growing to do that I would like to put a moonlight effect in. That could almost light a third of the backyard alone. The house is an old single story bungalo built in 1925 and I just think to light it right won't take a lot of wattage.

Wondering, too, why the hub method is thought to be unsafe.

Chris J
07-10-2007, 04:33 PM
James S.
Please don't make statements like that without giving us an explanation of why you feel this way. I don't use the Hub method at all, but I hardly think it is unsafe if it is used in the way in which it was intended to be used. I'm quite sure there are hacks out there that have manufactured their own home-made version of a hub that could be classified as unsafe or unworthy but these statements are somewhat harsh considering the company we are among in this forum.

Pro-Scapes
07-10-2007, 07:28 PM
I imagine going up to a 600W transformer I could outgrow that as well. Less is more in my opinion, for fixtures at least, and light amount. This seems to be the overall opinion in the design texts I've read and opinion I have from the overlit properties I've seen. I have a tree that has some more growing to do that I would like to put a moonlight effect in. That could almost light a third of the backyard alone. The house is an old single story bungalo built in 1925 and I just think to light it right won't take a lot of wattage.

Wondering, too, why the hub method is thought to be unsafe.

John... If you feel it would be over lit then thats your opinion... add less... its your home.... no one can tell you how you would like it. Alot of the pictures you see on this site tend to be over exposed making the photo much brighter than the original project. If all you want is a single moon light out back then do that. I preffer soft ground mounted lights as well as a moon light to define things a bit better but I always leave the ed decision up to my clients.

A small bungalo that is tat old should probably be softly lit... perhaps as it might of been back then. I would love to see some pictures of it. We will be building a classic island style outdoor cabana/bar/hot tube area here this winter and I am actually deating about stringing lights across it (similar to christmas lights) because this is how I rememeber my visit to a place like I am wanting to build in the bahamas.

You might also consider using lamps that would of been avalible in that period if your wanting to try and keep wit the original theme or at least using lenses to soften the light as they did not have bright halogens back then.

Mike M
07-10-2007, 08:39 PM
Chris is right,

I am wondering if James is referring to the use of a "hub" as an in-line junction box inappropriately used for direct burrial? Or maybe he is referring to the use of an indoor lv hub/junction, since he works with that, too?

Please explain, James,

Thanks,

Mike M

INTEGRA Bespoke Lighting
07-11-2007, 12:40 AM
Okay guys & gals.... Most hub wiring fans also make use of Multi-tap transformers that provide for voltages far exceeding the 14.4 (lets round up to 15v) that is permitted by CSA and UL for use in approved Low Voltage Landscape Lighting Systems. If you are in fact using a 16,18, or 22 volt tap on a transformer and feeding a LV lighting system with this, then you are not using an approved LV Landscape Lighting Transformer. Around these parts, that can get you in trouble.

I guess I am just old school when it comes to LV systems. I prefer to use UL1838 and CSA standards and I prefer to over build my systems to allow for future expansion as well as a very restful sleep each and every night. I am not telling anyone what to do here.... just be mindful of the rules and regulations. If we have "professionals" who keep breaking them out there then eventually it will harm the whole industry.

Have a great day.

johnquest
07-11-2007, 07:15 AM
Here are some photos of my house, the front and east side. What sort of lights would you work with for the front? In one picture the vine is now gone and I've since filled the front flower beds with plants and have taken out the bush on the front left corner. On the left side where you see the air-conditioner, that's where I will be mounting the transformer.

Mike M
07-11-2007, 07:52 AM
John, your run and your front is small enough to just buy some mr-16 bullets, wire, and a transformer, and move the lights around yourself to find favorite effects. Get a handful of bulbs--10w, 20w, 35w, at varying flood angels. You'll have a blast.

Pro-Scapes
07-11-2007, 09:54 AM
I like the house... classic craftsmanship. Before you run out and slam bullets in the ground also think about downlighting it... Only way to tell if you will like this is to try it. I would at least downlight (or consider it) the steps and possibly eliminate any path lights.

To really bring out the structure you may wish to light softly that 2nd story window. You can possbly mount some niche lights in the eves above it or use a soft small wash fixture maybe like the unique stellar.

Whats the lighting like under the porch... would be great if you could do 3-4 recessed.

James on the hub and higher voltages... not everyone that uses a hub exceeds 15v... My most common taps are 13 and 14v with the occasional use of a 15v. I think only on a rework with a tight budget have I gone higher and that was with the client declining to let me rewire it.

steveparrott
07-11-2007, 10:12 AM
Personally, I think the HUB method of wiring is totally wrong and boarders on un-safe and illegal.

Ok James, with all due respect, let's clear this up. your complaint about the HUB method seems to rest with UL 1838. The HUB method is simply a wiring configuration that, when done properly, does not violate any UL or CSA standard or NEC code.

As for safety, there has never been a reported serious injury from contact with any voltage below 30 volts. I researched this myself searching through OSHA, NIOSH and various engineering data bases going back as far as they've been keeping records.

While I understand your need to adhere to 1838 to satisfy local compliance requirements, we should all be clear that the 15 volt limit set in 1838 was a grossly over-conservative number based on conclusions from a 45-year old study published by the International Electrotechnical Commission (IEC), a WHO group. Other groups using results from the same study concluded that 30 volts should be the safe threshold - the NEC uses this 30-volt limit to define low-voltage. Throughout the past many years, many industry groups (irrigation, alarm, telecommunications, satellite, etc.) have gained 30 or 24-volt exemptions from electrical licensing requirements because it is generally known to be safe.

In fact, UL itself has been trying to change the voltage limit of 1838 for many years but certain industry groups have been blocking their attempts. A 2005 study released by the IEC now replaces the 1961 study as the definitive scientific conscensus. Their new conclusions - there is a negligable risk of death for any voltage below 30 volts.

ZX12R
07-18-2007, 07:28 PM
"James on the hub and higher voltages... not everyone that uses a hub exceeds 15v... My most common taps are 13 and 14v with the occasional use of a 15v. I think only on a rework with a tight budget have I gone higher and that was with the client declining to let me rewire it.
__________________"

My common taps have so far all been between 12 and 14 volts. This topic starting to confuse me a bit the more it goes on. Is it not perfectly fine to use taps higher than 15 volts if so needed?

sprinkler guy
07-19-2007, 03:54 AM
I guess I am just old school when it comes to LV systems.

James,
I wouldn't say old school, as much as diffrent school. There are many ways to wire a low voltage system (hub, T, daisy-chain, etc.). Depending on how you were taught, or which manufacturer you happen to be talking to at the time, opinions are very widespread. I see this as a Coke or Pepsi issue - which one do you like? They all work done properly, but no matter which method you use, there is always going to be some math involved and a volt meter to check voltages at fixtures.

The under/over 15 volt thing is a seperate issue, and if you can get some concensus of thinking on that one, you're a better man than I.

sprinkler guy
07-19-2007, 04:06 AM
I imagine going up to a 600W transformer I could outgrow that as well. Less is more in my opinion, for fixtures at least, and light amount. This seems to be the overall opinion in the design texts I've read and opinion I have from the overlit properties I've seen. I have a tree that has some more growing to do that I would like to put a moonlight effect in. That could almost light a third of the backyard alone. The house is an old single story bungalo built in 1925 and I just think to light it right won't take a lot of wattage.

John,
I'm with you on the less is more idea. I use a lot of bi-pin Xenon T-3 bulbs in uplights and for washing effects,10 and 15 watt, sometimes even 5 watt. I also do alot of systems in a city that doesn't have any street lights and only one stop light. Pro-Scapes makes a great suggestion on the downlighting, especially around the porch and the steps. If I was standing at the rail of the porch looking out, a poorly placed uplight could have some glare issues, while downlighting wouldn't.

Good luck; it's a great looking old house.

eskerlite
07-20-2007, 06:22 AM
If you have to use more than 15 volts, you are not placing enough transformers on the project. What happens to 2 of 3 lamps on a hub when one blows out its 300 ft of run and you use 12-2 pushing 18v? The other two are going to go in one day of the blow out. This is an example so dont get all scientific. I use a hub now and then but usually with 13-14v
max with a 100 watt draw at most, no longer than 100 ft with 10-2. How many people feel they NEED over 15 volts most of the time? Anyone using the RSL stepdown resistor?
Sean C.

ZX12R
07-20-2007, 11:03 PM
"If you have to use more than 15 volts, you are not placing enough transformers on the project. What happens to 2 of 3 lamps on a hub when one blows out its 300 ft of run and you use 12-2 pushing 18v?"


Why would anyone use 12-2 wire for a 300' run??? I specifically recall a seminar about 3 years ago where the owner of Cast stated that you can have a 500' run. Has that changed from that tme? Also,transformers have taps all the way up to 22 volts. Why would they make them ?

I am just trying to learn more than I know and not trying to sound like an idiot.Thanks for all replies!!!!!

Eden Lights
07-21-2007, 01:27 AM
If you have to use more than 15 volts, you are not placing enough transformers on the project.

I would agree with this statement, but it certain applications an 15-17 volt tap can allow some excellent additions to a design that would not happen otherwise. Example, small distant areas when line voltage is not a option.

What happens to 2 of 3 lamps on a hub when one blows out its 300 ft of run and you use 12-2 pushing 18v? The other two are going to go in one day of the blow out. This is an example so dont get all scientific.

When the load decreases, yes the voltage is going up and the remaining lamp life will suffer. All low voltage cable is fine with any voltage that we are discussing here 12-30Volts. Clients should be aware of these special runs and be commited to the increased maintenance issues. I am sorry, but it is scientific and this has nothing to do with a hub, other than people associate high voltage with hubs because of the Unique training and sales materials.

How many people feel they NEED over 15 volts most of the time? Anyone using the RSL stepdown resistor?
Sean C.

Not most of the time, but when you do properties with acerage it is a excellent tool when done scientifically for your tool bag to seperate you from the average installer.

Last I heard the RSL unit had been dropped?

NightScenes
07-22-2007, 12:44 PM
I do use transformers that go to 18v. Here in central Texas I have projects that are on 3 acres or more with no power available in remote locations. I have had need for the 18v tap on #8 wire before. This saved having to trench the clients lawn and add a new outlet to an area that really didn't need 120v. It also saved them about $1,000.

Pro-Scapes
07-23-2007, 12:55 AM
Anyone using the RSL stepdown resistor?
Sean C.

Never on a new install... more splices to fail and one more component that can fail. They do work tho as lng as you have enough voltage going to them.

I did use RSL internally regulated fixtures that were speced on a special install reffered to us by our dist... As far as I know almost 2 years later they are still ticking without missing a beat.

We HAVE used regulators on service calls for existing systems where the voltage was very out of balance. The clients declined to let merewire the systems. Before I fixed it... 8.2v.... After I fixed it.. 11.4v on a 15v tap with regulators installed at 3 fixtures then voltage drop bringing the rest in spec.

I hope these regulators dont turn out to be common place on new installs and guys forget how to use a volt meter. If you dont have high enough voltage coming in your never going to get it coming out.

ChampionLS
07-23-2007, 10:35 PM
Aight....

I have a question for Y'all. What is the minimal distance in feet to connect the first fixture from the transformer? I believe there is a 10 feet rule, but I'm not sure if this is manufacturer specific.

Thanks,

Anthony :waving:

Chris J
07-24-2007, 06:36 AM
I can't give you the scientific explanation, but I have also heard the 10' rule as well due to in rush current at power up. I would also appreciate it if one of the "techie" types would elaborate a bit more on the subject.