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GreenLight
02-20-2009, 10:55 PM
I was wondering what everyone's techique is for testing voltage at each fixture on a lateral run.

Example- Home run wire, teed off going to 6 fixtures...
For a while I was using the technique of removing the lamp on the fixture I was testing while leaving all other lamps on.....Obviously this reading would not be perfect as it is not accounting for the removed lamp and overall I was never thrilled with doing it that way...

Over the past 6 months I have been elevating the lamp while it remains in the socket and then testing from the socket while the lamp remains on. I know this way im getting a voltage reading that reflects all lamps being on and in use, but it's not the most user friendly method on certain fixtures.

Anyway, im just trying to get some insight from those in the know on the subject...I know a lot of people test where the lead of the fixture meets the lateral line, but I have always been skeptical about using this method because of varying lengths in leads and such. Any suggestions or criticisms are welcome.

The Lighting Geek
02-20-2009, 11:16 PM
The simplest way to combat that is to use the hub method with equal lengths of wire to your fixtures from the connection at the home run. If you use 25' on your fixtures you will experience approximately 1/2 volt drop to the fixture. I have installed literally thousands of fixtures this way and never had an issue and it is easy to duplicate with your employees. Unique Lighting came up with the method and has been promoting it for years.

Lite4
02-20-2009, 11:23 PM
Ditto what Tommy said, you can also buy a testing device from cast lighting for testing directly at the fixtures too.

GreenLight
02-20-2009, 11:28 PM
I am in complete agreement with you and trust me I still intend to do just that. I actually tried to make the hub method a selling point on this job I am doing now, unfortunately I caught some static from the landscape design group I am subbed by for this job. Basically they told me they were familiar with what I was presenting but to use their words "we don't want that spider splice bullsh*t with wires running in every direction in our planting beds" (their words, not mine, and yes they are hot and heavy about trying to get me to chain everything off of laterals).

I am all about using the unique hubs, trust me, I have just been dealing with the same designer for the past 3 months and he basically forces my hand on certain issues, hub method being one.

INTEGRA Bespoke Lighting
02-21-2009, 09:03 AM
I understand the "hub method", and understand it's advantages and limitations. Keep in mind, that on large, relatively sparsely lit properties it is not going to be all that effective. It will work fine for most typical urban / suburban lots, but not necessarily when you get into large, estate size properties. You need to educate yourself on all forms of wiring techniques and understand the advantages and limitations of each. That way you will be able to design and install the optimal system for the application. Ultimately the lot size, format, location of physical obstacles, features, and system layout will predict what wiring system is best for the job. Doing it right, each and every time keeps you on your toes!

Have a great day.

Lite4
02-21-2009, 09:41 AM
I agree with James. The hub is a great method of wiring and the one I use 90% of the time. But sometimes you run into situations where it just isn't feasable or necessary. If they have their panties in a bind about a hub and want everything chained, go to an LED offering for the lighting. It will give you much more flexibility in wiring. Hey James, check your PM.

MAGLIGHTING
02-21-2009, 09:58 AM
I was wondering what everyone's techique is for testing voltage at each fixture on a lateral run.

Example- Home run wire, teed off going to 6 fixtures...
For a while I was using the technique of removing the lamp on the fixture I was testing while leaving all other lamps on.....Obviously this reading would not be perfect as it is not accounting for the removed lamp and overall I was never thrilled with doing it that way...

Over the past 6 months I have been elevating the lamp while it remains in the socket and then testing from the socket while the lamp remains on. I know this way im getting a voltage reading that reflects all lamps being on and in use, but it's not the most user friendly method on certain fixtures.

Anyway, im just trying to get some insight from those in the know on the subject...I know a lot of people test where the lead of the fixture meets the lateral line, but I have always been skeptical about using this method because of varying lengths in leads and such. Any suggestions or criticisms are welcome.

Check the voltage at the connection at the first fixture on that homerun.
When you are using brass lugs it's easy. If you are using the hub method. Check the voltage at the hub

MAGLIGHTING
02-21-2009, 10:02 AM
I understand the "hub method", and understand it's advantages and limitations. Keep in mind, that on large, relatively sparsely lit properties it is not going to be all that effective. It will work fine for most typical urban / suburban lots, but not necessarily when you get into large, estate size properties. You need to educate yourself on all forms of wiring techniques and understand the advantages and limitations of each. That way you will be able to design and install the optimal system for the application. Ultimately the lot size, format, location of physical obstacles, features, and system layout will predict what wiring system is best for the job. Doing it right, each and every time keeps you on your toes!

Have a great day.

HUb set up is Great for beginners and not knocking it but I use it very very very seldom and never with 16 gauge cable in the ground. JS is right you need to know all forms of cabling methods.

steveparrott
02-21-2009, 04:44 PM
Here are the CAST tools for measuring voltage at the fixture with the lamp powered up (CTESTMR16, CTESTS8): (Note: I know I shouldn't promote our products here, but no one else makes these items.)

steveparrott
02-21-2009, 05:10 PM
When measuring voltage at the hub, keep in mind the voltage loss between the hub and the lamp. This voltage loss varies according to the lamp wattage, lead length and wire gauge.

After taking the reading at the Spider Splice subtract the following to estimate voltage at the lamp.

Fixtures with 25' #16/2 lead wire:

20W: 0.3v | 35W: 0.6v | 50W: 0.8v

Fixtures with 25' #18/2 lead wire:

10W: 0.3v | 20W: 0.5v

Fixtures with 35' #16/2 lead wire:

10W: 0.2v | 20W: 0.5v | 25W: 0.6v| 35W: 10.8v | 50W: 1.2v

steveparrott
02-22-2009, 01:26 PM
Fixtures with 35' #16/2 lead wire:

10W: 0.2v | 20W: 0.5v | 25W: 0.6v| 35W: 0.8v | 50W: 1.2v

Note correction to the last line of my previous post.

GreenLight
02-22-2009, 08:11 PM
I appreciate everyone's responses and overall I am on the same page with everyone and am familiar with varying wire methods. The main reason I was asking the question is because of the unique situation I am in currently where I am generally forced to run hybrid T's and or chained lights in order to please the designer and his preferences on planting beds and what not.

Other situations I run into are the ones where I go on a service call for work previously done by another contractor and I am pretty much sure they have one home run that goes all over the yard without a real strategic plan other than hooking up lights and getting it over with....

Thus I run have the need to figure out voltage at the lamp frequently without having a true protocol such as standard formulas or conventional wiring methods where I can simply do it mathematically. Like I said, I have been simply elevating the lamps on most of these in order to get an accurate reading of the voltage under full load. I was just curious if there was a better alternative when facing the circumstances I often face here. Steve, I would certainly be curious to get some info about the price of the MR 16 voltage testing product you displayed, I don't know what your practices are for displaying on a forum but if you could let me know one way or the other, the best way to get this info, please do....Thanks again everyone.

MEXANDME
03-14-2009, 08:20 PM
I put together the following "contraption:"

I took a pair of old volt meter test leads and cut off the ends that plugged into the meter. I used copper splice caps to connect the old volt meter leads to the wires coming off of a MR16 replacement socket.

So to test for voltage drop at a given light; I pull the bulb from the light, put the bulb in the MR16 replacement socket, plug the old OHM meter leads (which have the sharp pointed ends on them) into the light socket, and read the voltage on the copper splice caps with my volt meter.

I am sure there are much better ways....this is just my way.

Regards,

Ros

David Gretzmier
03-14-2009, 10:39 PM
I have that identical setup, but I also have a seperate set I built, the only change is I bent the tips to test the socket at right angles. I find that some deck puck lights and some path lights with bi-pins wont allow you to test with straight pins.

Infinity Landscapes, Inc
03-14-2009, 11:30 PM
I heat shrick all my hubs and leave a 1' pig tail caped that I can test when I can.

My 10 cents I label all wires to and under valve box lids. Just trying to make easyer for the guy who comes in after me. :)

INTEGRA Bespoke Lighting
03-15-2009, 01:28 AM
CAST makes some pretty good and easy to use voltage test leads that allow you to install the lamp on the fixture and take an accurate voltage reading at the same time. No need to build 'contraptions'.

Infinity: "The guy who comes in after me"??? How noble of you. I have a better idea though... it is called client retention! My way, there is no need to consider those who come 'after you' as it is a moot point!

Have a great weekend.

Eden Lights
03-15-2009, 01:38 AM
All connections are crimped barrels and grease tubes go on last before wire goes in the ground, so its pretty easy to setup voltages. I use a cast style device when I have to check after final installation of wire.

MAGLIGHTING
03-15-2009, 12:36 PM
Use a connector like this and you'll never have the need to rig a contraption

Infinity Landscapes, Inc
03-15-2009, 12:52 PM
I know I am the one who is all ways doing the repairs etc for my clients. so I guess I'm making it easyer for mua. whenever I go into a new lighting repair I alway think what was this guy thinking if he was at all or everthing is nice and neat for the guy after him.

Go Halogen
03-15-2009, 02:49 PM
When promoting the hub, let's not forget about the pit falls involved.
Three biggest flaws that I come across:

#1 - Limits lamp usage per hub (I use 10w, 20w, 35w on same runs.
Hubs are not great for this. The fixtures on a Hub need to be clones.

#2 - Fixtures placed side be side or in close proximity....What to do with all of the excess wire?? Most just bundle it up and bury it. Not good. Lots of waste and when the system is running it creates nice warm nesting sites under the soil. Rodents love to nest in these nice warm spots and they love to chew on wire.

#3 - The outstretched pigtails running through the beds create too many points of possible cut throughs. I run my wire close to foundations, walkway edges, and curbs. No one digs in these spots. You can not be really neat with hubs.

I do use hubs when it make sense, but for the most part they take away from being creative and it just brings up the cost of materials.

I find myself maintaining more systems now and many of these were not my installs. The hub accounts always seem to be more work. Wire every where.

- Andy

INTEGRA Bespoke Lighting
03-15-2009, 03:20 PM
Andy: in regards to your #2 item above: Years ago I recall that some manufacturer(s) of LV lighting cable were putting denatonium benzoate (the world’s most bitter substance) into the PVC jacket formulation of their cable. This was in an effort to stop rodents from chewing through the jacket. I do remember having this issue in some of my first installations, dating back 10-11 years ago, but have not noticed any issue with it in a very long time. Perhaps this is now completely common in the cable jacket composition? I don't know about 16ga lead wires, but I also don't use the hub method all that often, and as a result don't have coils of lead wire burried.

Has anyone else found chewed through circuit or lead wires in the recent past?

David Gretzmier
03-15-2009, 06:53 PM
Ultimately if you allow a light to be added in the future on a run, and if your voltage on all fixtures on a run is between 10.5 and 11.5, I think I can sleep at night.

JoeyD
03-16-2009, 11:23 AM
When promoting the hub, let's not forget about the pit falls involved.
Three biggest flaws that I come across:

#1 - Limits lamp usage per hub (I use 10w, 20w, 35w on same runs.
Hubs are not great for this. The fixtures on a Hub need to be clones. You can use different wattage lamps...Same wattage helps but isnt neccesary..
#2 - Fixtures placed side be side or in close proximity....What to do with all of the excess wire?? Most just bundle it up and bury it. Not good. Lots of waste and when the system is running it creates nice warm nesting sites under the soil. Rodents love to nest in these nice warm spots and they love to chew on wire. You can cut wire leads down as long as you know your VD from Hub to fixture. But when eliminating wire lead you eliminate a lot of flexability should you ever need to move the lights in the future.

#3 - The outstretched pigtails running through the beds create too many points of possible cut throughs. I run my wire close to foundations, walkway edges, and curbs. No one digs in these spots. You can not be really neat with hubs. Why cant you run your wire leads along planter bed edges, curbs, or walkways with a Hub? We do all the time. You should always try and run wire along an endge and then strait out to the light. This is no different than any other method....

I do use hubs when it make sense, but for the most part they take away from being creative and it just brings up the cost of materials. Wha wha what? Cost of materials? Well I guess if you have to run your own fixture leads and then have to make a connection at every light but if your fixtures come with pre-wired leads then your cost of materials should go down being you only need to make one connection for every grouping of lights......How does it limit your creativity, the picture in my signature is all Hub method

I find myself maintaining more systems now and many of these were not my installs. The hub accounts always seem to be more work. Wire every where.



- Andy

I would rather work on a hacked in Hub system then a hacked in daisy chain...you can work with a Hub! You cant blame the wiring method because the installer was being lazy. It is all in how you install. We teach guys to wrap the wire and bury it by the light, not at the Hub. You could coil it up and zip tie it or some choose to wrap it around the stake. We teach guys to label all runs on each end of the wire, and mark the Hubs identifying which transformer it is being powered by. We also teach inline fusing at the hubs. Tell me one other wiring method that has the flexability of the Hub should you ever need to add or remove a light from the system. What about if you need to move lights after future growth? Better yet which method works better for distributing equal voltage to all lamps??? There is only one method thats more flexible and that is the Trunck and branch method for 24v systems.

Hubs and transformers are only as good as the installer putting them in!!!!

NightLightingFX
03-16-2009, 12:24 PM
Mike & James enlighten me,
What wiring methods do you use? I can't believe you guys use the "Daisy Chain." Don't you think the "T Method" is basically the same as the "Hub?"
~Ned

Go Halogen
03-16-2009, 09:01 PM
Joey....You seem to have an answer for everything....as long as it benefits your Brand. Step back and take a look at what you are saying. Everyone knows the marketing strategy of Unique and Cast.

Most of the time fixture leads in your "Hub" method can not be tucked along foundations, along edges, etc. 25 ft. is not enough to do all of that. There is often much wire in and amongst the beds. I see it all of the time. You can not call your installers hacks....You and your guys taught them how to drink the coolaid.....remember??

The "T" method is similar to a hub, just played down a bit. But it gives you the flexibility to design more. In most cases you do not need 25' of lead. It is a wasteful expense associated with increased fixture cost.

Does Unique offer shorter leads? I six to eight ft. on my fixtures. That is more than enough.

Guys...I drank the coolaid a long time ago....but I realized later that there were better methods.

- Andy

MAGLIGHTING
03-16-2009, 09:49 PM
Mike & James enlighten me,
What wiring methods do you use? I can't believe you guys use the "Daisy Chain." Don't you think the "T Method" is basically the same as the "Hub?"
~Ned

I've stayed out of this debate because I have lot of respect for Unique and Nate. I very much like Joey, I think he is a great guy and really knows his stuff.

That being said I will share my opinion because I have been directly asked.
Nothing personal Nate and Joey, just my feelings and preferences.

I feel the hub method has been designed as a "crutch" for new installers to make it easier for them to load balance their systems. It was designed to take all of the difficulty out of enginnering a low voltage system. There really is not much of a challenge to achieving proper voltage at the lamps. This in and of itself has made entry to installation and learning curve much easier for many.

There are a few things I don't like about this set up.


I don't use anything less than 12 gauge cable in my systems. 25' of 16 and or 18 gauge wire on every fixture is wasteful, puts an unnecesary load on your transformer which results in wasted electricity. Burying excess wire is wasteful as is cutting it off and disgarding it or throwing it in the truck to gather dust and take up space. Cutting the wire short defeats the purpose of paying the premium for the unused wire in the first place. When you are installing fixtures everyday this is significant.

I don't like the transition made from the teflon wires of the socket to the 18 or 16 gauge wire. Most times it's located right outside the stem of the fixture and made with butt connectors or soldered and covered with regular heat shrink tubing. Either way it has a potential to fail.

I don't like the small hub that is marketed by some manufacturers. It's very hard to find after installation and hard to fit all the wires in and work with. Sure you can make your own, use a larger valve style cover box or such. Putting metal in the box is not good. The metal will rust and I don't need to add another tool to my truck by way of a metal detector.

First and foremost it limits your use of 15 volt maximum transformers. All that small gauge cable puts unnecesary added load, resistance and increased voltage drop on the transformer. It also consumes more of your client's electricity. I don't wish to get into a debate but the reason I don't use 15 volt plus transformers is because of the increased risk of lamp failure. You lose 1 35 watt lamp on a 20 volt tap cable run and all of your lamps on that run are now in excess of 12V. I know Unique has fought this vehemetly but my experience and my voltage meter always tell me that this is what happens. The longer the run and greater the load the bigger the problem. And when do you use the higher taps? When you have longer runs or heavy loads. Otherwise there is no need.

I feel the main reason this system has been heavily promoted is because of the fact that it encourages the use of Uniques transformers which go up to 22V. Now don't shoot me, I don't say this derogatorily , in fact it was a great marketing angle until competitors jumped in and started offering competing materials. When this system was originally promoted you have to remember that Unique was the only manu offering the equipment with long leads and up to 22V multi tap transformers, hubs etc.

It's unfortunate that there are many guys who learned lighting with the hub method and know no other way. If they can't get their long leads and 22 volt transformers they are lost.

I've done projects on multi acre properties, I have one project going now that is 275 acres and I have never ever once had the need to install a transformer that exceeds 15 volts. And everytime, without failure I have proper voltage at the lamp and I have more headroom on the transformer too.

It's nice to be able to put all or most of your transformers in 1 location on a project. However more times than not it is not practical or even cost effective to do so even with a 22 volt transformer.

I don't wish to turn this into a big brawl. That is not my intention. This is only my opinion and preference. Nothing more and nothing less. If you love the hub and the 22 volt transformer and you are comfortable working that way then keep doing what you are doing.

If you love the 24 volt system then go for it.

Unique is one of the better manufacturers out there and has done great things for this industry. Doesn't mean that I agree with all of their philosophies or they of mine. However you won't find me out there lobbying to anyone for them to lose their ability to do what they do and teach what they teach. They have every right to do so and I respect their right to do it.

Go Halogen
03-16-2009, 10:04 PM
Very well put. I liked the elaboration.

Marketing is everything and the newbies in the industry are the prey.
Those of you who visit this Forum often know better.

Make it easy, make simple, make it work....???? No!!
Use your mind, gain ability, make it right.....Yes!!

Andy

INTEGRA Bespoke Lighting
03-16-2009, 10:52 PM
Ned: What can I possibly say that Mike did not already? Very well explained Mike. I concur with him 100% on each and every point in his response.

MAGLIGHTING
03-16-2009, 11:49 PM
Ned: What can I possibly say that Mike did not already? Very well explained Mike. I concur with him 100% on each and every point in his response.

Thank you James.

NightLightingFX
03-17-2009, 12:22 AM
Mike,
Thanks for sharing that. Keep in mind I am not arguing I am just trying to learn more effective ways to engineer. Help me understand the differance between the "T" vs. the "Hub." Lets exclude Unique in this discussion. And lets pretend we are only using fixtures with 5' leads attached to them.

Isn't the only difference between the "Hub" vs. the "T" is that in the "T" method, the middle fixture is the hub. Other than that they are the same. With everything you laid wouldn't the hub be just as effective? I guess the only differance is in the hub there is a designated irrigation box with all the connections vs. making all the connections at a fixture? and in the "T" one lamp is getting a little more voltage from the homerun where all the other lamps are getting a slite voltage drop?
~Ned

The Lighting Geek
03-17-2009, 12:25 AM
That was very respectfully done, Mike. Your posts make all of us think more about what we do, and how we do it. Sometimes it challenges us to keep an open mind and that is a good thing.

NightLightingFX
03-17-2009, 12:41 AM
You lose 1 35 watt lamp on a 20 volt tap cable run and all of your lamps on that run are now in excess of 12V. I know Unique has fought this vehemetly but my experience and my voltage meter always tell me that this is what happens. The longer the run and greater the load the bigger the problem. And when do you use the higher taps? When you have longer runs or heavy loads. Otherwise there is no need.



I am not challenging you I am just searching for answers. In my experiences with Uniques transformers I see very little voltage drop when a load is put on the transformer. So regardless, if a one lamp burns out on a long homerun that used a 20v tap, if the that hub was getting 11.5 volts why would it be any different from a shorter hub that used a 15v tap and it was getting 11.5 volts also? However if you use a Kitchler transformers I can FULLY understand the problems a burnt out lamp would create if it were on a 20v tap.
~Ned

INTEGRA Bespoke Lighting
03-17-2009, 12:50 AM
Man, the company that begins with a "K" and ends with an "r" sure takes a beating on good ol' Lawnsite don't they?

I wonder if 'they' will ever come out with their own line of transformers? Now that might be interesting. I wonder why they have not bothered to do this yet. Surely those MDL's they sell now have received enough bad reviews to encourage them to put some resources into this.

MAGLIGHTING
03-17-2009, 01:09 AM
Mike,
Thanks for sharing that. Keep in mind I am not arguing I am just trying to learn more effective ways to engineer. Help me understand the differance between the "T" vs. the "Hub." Lets exclude Unique in this discussion. And lets pretend we are only using fixtures with 5' leads attached to them.

Isn't the only difference between the "Hub" vs. the "T" is that in the "T" method, the middle fixture is the hub. Other than that they are the same. With everything you laid wouldn't the hub be just as effective? I guess the only differance is in the hub there is a designated irrigation box with all the connections vs. making all the connections at a fixture? and in the "T" one lamp is getting a little more voltage from the homerun where all the other lamps are getting a slite voltage drop?
~Ned

That is correct Ned. I like to have all of my connections right at the fixture locations not in a remote location so this way I always know exactly where to find them. It's not a matter of effectiveness. The hub method is effective. It will get the job done. It's a matter of not having small gauge wire running all over the place or cut off or coiled up somewhere and require more powerful transformers to power the fixtures. Again it's not the power that I object to, it's the potential to burn out lamps when 1 or more fail on a line (I'm sure Joey is going to have something to say about this but nothing can convince me otherwise as I've seen this scenario so many times in the field). 12V lamps were designed to operate at a maximum of 12volts for lamp life and efficiency. If you are not diligent about changing burnouts right away then you are going to have trouble. MR-16's and PAR-36 halogen's have pretty good filaments and will withstand some over volting although it will shorten their life. Xenon, xelogen, bi-pins and forget about incandescants they will not tolerate it.

There are very few instances where I would use the hub method that it would be neccesary. In the cases were I would use it, it would be with 12 or if needed 10 gauge cable and 15V maximum output transformers and 6" minimum valve cover boxes. As usual all of my connections made with brass lugs and marine grade adhesive lined heat shrink.

The short answer is yes, take away the cable gauge, remote wire connection method and exact voltage at every fixture (which is not neccesary) and indeed essentially the two methods are very similar.

MAGLIGHTING
03-17-2009, 01:10 AM
That was very respectfully done, Mike. Your posts make all of us think more about what we do, and how we do it. Sometimes it challenges us to keep an open mind and that is a good thing.


Thanks Tommy. You are a credit to the game.

MAGLIGHTING
03-17-2009, 01:17 AM
I am not challenging you I am just searching for answers. In my experiences with Uniques transformers I see very little voltage drop when a load is put on the transformer. So regardless, if a one lamp burns out on a long homerun that used a 20v tap, if the that hub was getting 11.5 volts why would it be any different from a shorter hub that used a 15v tap and it was getting 11.5 volts also? However if you use a Kitchler transformers I can FULLY understand the problems a burnt out lamp would create if it were on a 20v tap.
~Ned

why don't you test it for yourself and see. Run a 150' 12 gauge homerun to your hub and install 5 - 35 watt lamps with 25' 16 gauge leads attached to them. Hook that homerun to whatever tap will give you as close to 12V at the hub (voltage drop at the fixture should bring you around 11.6 or so). Disconnect 1 of the fixtures to simulate 1 bulb burned out and test your homerun again
and see what you have. Disconnect another and see what you have and I know you will then see what I mean.

NightLightingFX
03-17-2009, 02:45 AM
why don't you test it for yourself and see. Run a 150' 12 gauge homerun to your hub and install 5 - 35 watt lamps with 25' 16 gauge leads attached to them. Hook that homerun to whatever tap will give you as close to 12V at the hub (voltage drop at the fixture should bring you around 11.6 or so). Disconnect 1 of the fixtures to simulate 1 bulb burned out and test your homerun again
and see what you have. Disconnect another and see what you have and I know you will then see what I mean.

Correct me if I am wrong. If I use a transformer that doesn't have voltage drop under a load. And I have two hubs both with 5 x 35W lamps on each hub. And both hubs are getting 11.5 volts. The only difference between the hubs is one is 150' at a 20v tap and the other is 75' 14v tap. If both hubs have a burn out at the same time. Won't they will still have the same voltage??? Regardless of the tap, the hubs have the same voltage and the same load just a different distance. Does that distance make a difference???

I will research this on my own also on my next job.
~Ned

MAGLIGHTING
03-17-2009, 09:17 AM
Correct me if I am wrong. If I use a transformer that doesn't have voltage drop under a load. And I have two hubs both with 5 x 35W lamps on each hub. And both hubs are getting 11.5 volts. The only difference between the hubs is one is 150' at a 20v tap and the other is 75' 14v tap. If both hubs have a burn out at the same time. Won't they will still have the same voltage??? Regardless of the tap, the hubs have the same voltage and the same load just a different distance. Does that distance make a difference???

I will research this on my own also on my next job.
~Ned


There is no such thing as a transformer that doesn't have voltage drop that's #1. Yes the distance means alot. Long runs have more resistance in the cable thus more voltage drop. You use the higher taps to compensate for loss in the wire and voltage drop from load. As the load is decreased or taken off the line at that distance (ie-burned bulb) voltage goes up. There is no transformer available right now that has an automatic compensation for this. The longer the distance and greater the load the more effect you will see in a rise in voltage once the load is decreased.

When all of your load is located at the end of a long run (100' plus) you have significant voltage drop from the transformrer. Much greater percentage wise then when your runs are shorter.

INTEGRA Bespoke Lighting
03-17-2009, 09:41 AM
Mike. Have you ever seen, used or tested the Cooper StableVolt tranformers? They have a circuit within that regulates the output to maintain a constant voltage. They are not listed specifically as a "Landscape Lighting" transformer, but I have seen them installed on the interior of a structure powering up some outdoor lighting.

Perhaps it would be worth tearing one down and seeing if the internal circuitry could be applied to another "top of the line" transformer. Thumbs Up

Regards

NightLightingFX
03-17-2009, 11:21 AM
OK, I will physically test this scenario today. Since I am in between projects, (I hope I get something else soon:cry:) I have time today. I have a 840W Unique demo transformer I can use.

JoeyD
03-17-2009, 01:04 PM
I have fought this battle for years, and I have explained all of our system on this site a bunch of times. The HUB is not the only way to wire a system correctly, like Mike said we developed the Hub system to simplify lighting and take the guess work out of VD. There are many rules to follow with a T, distances you cannot exceed especially if you like to use 12ga cable. The Hub also has rules and has limitations as does any other system but the Hub should not be blamed for the work created by individuals.

The Hub gives a housing for a connection, that's it. Most guys still like to bury silicone wire nuts in the ground. The Hub allows for one connection per every grouping of fixtures vs. 2 connections for every fixture that without a doubt are going to be buried in the ground. Not everyone takes the time to make connections like Mike G. does, matter of fact MOST don't!

Go Halogen, we do not refer to our contractors as Hacks, nor do we force anyone to drink KoolAid (If I am running for president then you must be running for captain original with that comment). My comment about hacking a system in goes out to all guys who refuse to take the time to coil wires neatly, run conduit to transformers, and come back to adjust the lights at night. We can teach guys the system we cant teach them to be good, diligent, and detailed installers. Don't blame the SYSTEM for another guys poor workmanship and don't blame us because we created a system that works and is very easy to learn. Bottom line is if you give me a project I can install a Hub system perfectly, have it work flawlessly, and have all the wires ran beautifully because I know how to take my time and not HACK a job in.

Last time I checked Unique Lighting signed my checks, we do not sponsor Lawnsite for our health. We do it so we can openly promote our products and systems. I am sorry if that bothers you. I like to think we are doing the site a service being that no other manufacturer seems to want to take the money or time to do what we are doing here. I am self serving most of the time I agree but I will be the first to tell someone to go elsewhere if I feel they have a better product for the situation. Those who know me know this to be true.

As for the fixtures we sell, yes you can order them from us with any length lead you want and you can order them with no lead or no lamp if you choose.

Mike is also correct that the higher the tap you use the quicker the chain reaction burnout may be but it is all relevant. If you have lights on the 14v tap and lamps burnout, voltage increases there as well. Chain reaction burnout is an inherent problem with LV lighting not just the Hub or because of higher tap transformers.

So again, Mike makes very valid points, bottom line is if done correctly you can make a T and a Hub work just fine. But Hacked in you can create havoc with either method. If every installer did the kind of work Mike did then we may have never even tried to think of a better or simpler way of wiring a system. Good thing for us we did invent the Hub because it has been a huge innovation for the industry.

NightLightingFX
03-17-2009, 04:47 PM
Mike,
Thanks for alerting me to this issue and inspiring me to find the answere for myself. This is what I found using a 840W Unique transformer and 5 x 35W lamps on 16ga. leads:
1) Long run 12ga. (163'), 20v tap, 5x35W lamps voltage at hub = 12.4v, 4x35W lamps voltage at hub = 13.9v. That is a 12% voltage increase.

2) Short run 12ga. (63'), 16v tap, 5x35W lamps voltage at hub = 12.5v, 4x35W lamps voltage at hub = 13.2v. That is a 6.7% voltage increase.

Something to think about. I was under the impression that this problem was a voltage drop issue with cheap transformers. In this experiment I did, voltage drop from the transformer is not an issue because the "Long run" and the "Short run" were tested individually.

I am going to ponder this revalation more. At some point I will probably have more engineering questions for you. At that time we will make a new thread regarding engineering.
~Ned

NightLightingFX
03-17-2009, 05:10 PM
The voltage drop due to a load on the transformer I experienced on the long run was:
- Yellow Tap without a load = 21.4v
- Yellow Tap with load of "Long Run" = 20.4v

JoeyD
03-17-2009, 05:28 PM
The higher the tap the larger the load increase.........this is why we use an 80/20 rule....if you wire up on the 12v tap only you can get almost the entire 840w on the unit....

What you have shown though Ned is that if you lose a lamp the voltage increses quite a bit weather your on a higher tap or a 15 or 16v tap. It is all fairly relevant although it is higher on the larger taps. Its a fair trade to being able to power those lights up properly 163ft away from the unit.

LiteEmUp
03-17-2009, 05:52 PM
What was the point of this thread again? Oh yeah...Hub Method Takes on The World. I mean what is the best way to check voltage at the lamp.

I started my lighting career in 1994. Now thats not forever by any stretch of the imagination. Ive used Nightscaping, Kichler, FX, Vista, Hadco, Focus and Unique. Ive wired with 12gauge 10 gauge Daisy Chain Tee and the Hub. Ive also used transformers that tap out at 12, 14, 15 and 22volts and now 30volts of course.

Ive installed fixtures on zero lot lines and large Ranches in Texas, multi Acre Estates along the Potomac River and RowHome Backyards and Fronts in DC. All of these jobs had some intricate nature to it either with masonry, carpentry, outdoor kitchens, elaborate congested plantings or wide open fields with "ancient" oaks.

I have had great success with all of the wiring methods i used upon the initial installation...always checking my voltages before i water sealed the connections. Over time if there were any issues with lamps burning, wires being cut, fluctuations in voltages, fixture placement, etc etc and so on and so on i found it necessary to check everything to make sure the system was still in tack. As my experience evolved i found certain methods of wiring gave me certain advantages not only when installing but while troubleshooting and tweaking a system which was even more important when it came to utilizing my time effectively.

Through all this i have found that the Hub wiring method and Unique have provided me with the most cost effective, easy to install and troubleshoot, lowest maintenance, least wasteful of time energy and materials, cleanest finished product, most flexibility, most adaptable, most reliable and profitable low voltage lighting system on the market and i don't even like Kool-Aid.

Do the math. If im running 180 watts 200' out to a large oak im using one 12/2 wire on a 22volt tap. Sure i might have to bury a few extra feet of 16/2 wire at the base of the tree when im done but hey it allows me to reposition the fixture in the future without having to re-wire the sucker. Now if i was using my old standby FX transformer (not picking on these guys) I would have to run 5 FIVE 12/2 wires to this same tree to accomplish the same thing using their 14volt tap and UNDERVOLTING isnt any better for your halogens than overvolting. Which system is more wasteful on wire...huuummm?

Now those fixtures keep burning out in the tree and i need to check those voltage and amperages to make sure somethin funnys not goin on. After i replace every lamp I guess i could check the voltage at every light in the tree since this isnt really a T method anymore but some sort of modified T so i dont know which fixture is really further from the T connection then the other. So i cut all the connections and redo them so i can test the voltage....except on the ones where i used wire nuts and electrical tape...those are easy. or i first replace all the burnt out lamps in the tree then climb my way back to every fixture and take them apart again to use some fancy tool to now check the voltage at one fixture then move on to the rest...each time repositioning the ladder and undoing fixtures...sounds like a very efficient use of my time...but at least i dont have to bury a couple extra feet of wire.

Or i go to the Hub at the base of the tree undo the lug caps test the voltage, amp probe all the leads to make sure those are fine and grease and cap and go.

And god forbid if something has changed that i now need to drop a volt at the transformer tap...then i have to go retest all of my voltages on those fixtures again.

Proper planning and design will ensure that most lead wires will end up in the same trench and not have a random path through the landscape. Unless you are installing your fixtures at night you better have some extra wire at your fixture to achieve the right affect...but those that don't probably have never visited their jobs at night.

Kool-Aid is served on both sides of the isle and if you dont even taste it you are bound to do what youve always done and not take advantage of new ideas. It doesnt have to be complicated with ficticious voltage drop coefficients or overengineering with 8 gauge wire. It just needs to make sense electrically.

The answer to this question is simple...don't test voltage at lamp...check it at the fixture whether yours comes with a 3" lead or a 25' lead. I find it easier to check 4 or more fixtures at once at the hub. No im not lazy, just efficient. And Joey D....NEVER CUT THOSE LEADS....unless you need a few feet to wrap around a competitors fixture to yank it off the tree.:laugh:

To learn more about why you need an amp probe contact Nate Mullen...i dont think he will mind. make sure you have a mirror available.

JoeyD
03-17-2009, 06:29 PM
HAHAHAAH..........Have a mirror.........now thats a funny story!!

Thanks for posting LightEmUp. To each his own, the Hub method definitley works and installed correctly it is in our opinion (not that it matters as we serve Kool Aid) the best method to use!

And as for my long winded post above, before Go Halogen sees this I want to apologize, yet again I got a little defensive and now I cant edit my lashing out....I apologize. I do take things personal at times when I shouldnt...I mean come on, were talking about landscape lighting....LOL

NightLightingFX
03-17-2009, 06:56 PM
The higher the tap the larger the load increase.........this is why we use an 80/20 rule....if you wire up on the 12v tap only you can get almost the entire 840w on the unit....

What you have shown though Ned is that if you lose a lamp the voltage increses quite a bit weather your on a higher tap or a 15 or 16v tap. It is all fairly relevant although it is higher on the larger taps. Its a fair trade to being able to power those lights up properly 163ft away from the unit.

Joey,
I agree, I believe it is a fair trade being able to power lights at larger distances. But the issue of an extreme voltage increase is something to be aware of. I am assuming Mike is able to go long distances with a 15v tap max by using bigger ga. wire. Using bigger ga. wire for long distances is something I will consider more often. I like having a transformer that has high voltage taps even if I don't use them. They are aways handy if you find yourself in an engineering pickle or last minute changes to the design and etc.

I have evolved in my engineering. I like using the "Hub" system for personal reasons. But just because I use the "Hub" system that doesn't mean that every lead is 25' long and that I bury a bunch of wire at the fixture. When I need a long fixture lead over 25' long I use 14 ga. or 12 ga. wire. I have kind of been evolving in using different ga. wire to compensate for different lengths. That way all the lamps in a hub are getting similar voltage.

One thing I will critize Unique for, as far as what I learned from them is that a 16 ga. 25' lead will have a voltage drop of -.5 volts. What I have found out through experimentation and then confirming with the voltage drop formula is that this is only true for a 20W lamps. A 35W lamp will have a voltage drop of -.7. To me a .2 voltage difference is kind of significant when trying to engineer a lighting system. It is interesting that Unique includes 35W lamps with their fixtures. (If I am wrong on this observation PLEASE correct me) Joey I am not piling on you. I am just sharing an observation. I highly respect Unique I am just pointing out something I have observed and I am just tying to be honest on and non biased. I am biased about your transformers - I love them.
~Ned

LiteEmUp
03-17-2009, 07:11 PM
Ned: What can I possibly say that Mike did not already? Very well explained Mike. I concur with him 100% on each and every point in his response.

Wow who's drinking KoolAid? How can you concur with someone 100% of the time? I may like Unique but i can find something in everyone of Joey Ds posts i dont 100% agree with.

Some how this became an attack on Unique and their marketing campaign.

Why does something that makes sense and is easy to use have to be for "beginners". Is there some law that says the more complicated and difficult a product is to use the better it is??? http://www.theonion.com/content/video/sony_releases_new_stupid_piece_of I tend to believe its because these people just dont get it and they want to say that its easy when its really too hard for them to grasp.

And how is Unique or any other manufacturer who has a "hub" method responsible for the work of the independent contractor doing the work out in the field??? They have no ultimate control over some crackheads desire to cut corners.

Man ive never seen so much Anti-Unique Anti-Hub KoolAid served at one taco stand before.

I guarantee that any lighting challenge out there can be properly designed and installed with a savings in total wire cost and labor using a central point connection system, spider splice or hub wiring method whatever you name it. If you want to pm me your sophisticated wiring plans i will design it for you and do the side by side comparison...we can post the results here.

JoeyD
03-17-2009, 07:19 PM
No worries Ned, we always have rounded to a .5v because we cannot always be sure if the person is running a 10, 20, or 35w lamp. It is an easy way for us to explain the system. It goes along with why only tell guys to use 5 lights assuming they use 35w on 12/2 that would max the cable out..it is easy to remember....but as you learn the system you learn everything you can do like running further than 25ft but bumping up to a larger guage wire lead. Or putting more than 5 lights if your using lower wattage lamps....

We always set general rules, like 200ft with 200w on 12/2 you will need a 22v tap....it is easy to remember but legally you couldnt put 200w on 12/2 you can only put 192....its just an easier way to remember things. If we explained that its .3 on 10w, .5 on 20w, and .7 on 35w it can get sort of confusing for the novice.

I need to remember that everytime someone questions our system that they are not questioning my man hood!! LOL

NightLightingFX
03-17-2009, 07:42 PM
No worries Ned, we always have rounded to a .5v because we cannot always be sure if the person is running a 10, 20, or 35w lamp. It is an easy way for us to explain the system. It goes along with why only tell guys to use 5 lights assuming they use 35w on 12/2 that would max the cable out..it is easy to remember....but as you learn the system you learn everything you can do like running further than 25ft but bumping up to a larger guage wire lead. Or putting more than 5 lights if your using lower wattage lamps....

We always set general rules, like 200ft with 200w on 12/2 you will need a 22v tap....it is easy to remember but legally you couldnt put 200w on 12/2 you can only put 192....its just an easier way to remember things. If we explained that its .3 on 10w, .5 on 20w, and .7 on 35w it can get sort of confusing for the novice.

I need to remember that everytime someone questions our system that they are not questioning my man hood!! LOL

I understand where you are coming from. This was something that was sitting in my craw for a while. I just had to mention it. When I figured this out it kind of bothered me that my systems weren't engineered to the specs I thought they were. For me personally, try to get 11.2v to my lamps but if I have to error on being too high or too low I error too low. In some situations that extra -.2v will be a significant consideration.
~Ned

JoeyD
03-17-2009, 07:45 PM
Absolutly......Sorry for the confusion Ned!

Go Halogen
03-17-2009, 10:10 PM
Joey - please do not apologize for your comments. I expected a full rebuttal.
I have a bit of disregard for the Hub (as you could tell). I have seen some poorly designed hub layouts through the years. Many of which could not be helped. It was the nature of the beast.

I agree with Mike G., when he termed the "hub" as a crutch.

The "T" method is not just tapping into the middle of the run, based of fixture quantities. It is tapping into the middle of the wattage on a given run.
Its nice to mix up wattages on any given run. I run a lot of 10s and 20s on the same run, to establish a layering effect and subtle 3-D curb appeal. I do not like setting up a curtain of even output.

Anyway....no hard feelings on my part. I appreciate anyone who voices a strong opinion.....right or wrong.

Andy

MAGLIGHTING
03-17-2009, 11:40 PM
Mike. Have you ever seen, used or tested the Cooper StableVolt tranformers? They have a circuit within that regulates the output to maintain a constant voltage. They are not listed specifically as a "Landscape Lighting" transformer, but I have seen them installed on the interior of a structure powering up some outdoor lighting.

Perhaps it would be worth tearing one down and seeing if the internal circuitry could be applied to another "top of the line" transformer. Thumbs Up

Regards


I inquired about that while designing my transformer and no one seemed to think it was possible at the time. I was calling it a voltage regulator. But then again all the major manu's also told me that .5 incremental taps were not possible but they were wrong about that too.

Thanks for bringing the availability of such a device to my attention James.

MAGLIGHTING
03-17-2009, 11:55 PM
Mike,
Thanks for alerting me to this issue and inspiring me to find the answere for myself. This is what I found using a 840W Unique transformer and 5 x 35W lamps on 16ga. leads:
1) Long run 12ga. (163'), 20v tap, 5x35W lamps voltage at hub = 12.4v, 4x35W lamps voltage at hub = 13.9v. That is a 12% voltage increase.

2) Short run 12ga. (63'), 16v tap, 5x35W lamps voltage at hub = 12.5v, 4x35W lamps voltage at hub = 13.2v. That is a 6.7% voltage increase.
Something to think about. I was under the impression that this problem was a voltage drop issue with cheap transformers. In this experiment I did, voltage drop from the transformer is not an issue because the "Long run" and the "Short run" were tested individually.

I am going to ponder this revalation more. At some point I will probably have more engineering questions for you. At that time we will make a new thread regarding engineering.
~Ned

yes assuming a .7V drop between hub and fixture with 16-2 you have 11.7V at each fixture in your 163' 12-2 cable run scenario and when a bulb goes out you have 13.2V. If you don't change that burned out lamp immediately you are going to lose all of the other 4 bulbs on that run too. What happens when you lose another bulb. The voltage spike is alarming and only gets worse with each succesive burnout.

And then the next step which hasn't been mentioned yet. Once you've taken that kind of load off your transformer the voltage not only goes up on that cable run but on every single other run on that transformer. So now you have put all lamps burning on that transformer in peril.

Voltage drop and increase in voltage is not only realized at the individual cable run but across all power taps of the transformer.

Yes it is convenient to be able to run long distances from your transformer however not at a substantially increased risk of losing bulbs to premature burn out .

You change your bulbs out immediately and you have no problem. Who is ready willing and able to provide that type of lightning fast service? Even more compelling. Who is going to pay for it?