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johnquest
08-06-2007, 11:38 AM
I'm seeing something I don't understand in my voltmeter. I have 4 fixtures with 21W single contact S-8 bulbs connected at a spider splice with a 27 foot 12ga run. I have one other light (21W) on a 12ga run by itself 73 feet. This single light is connected to the 12v tap. The spider splice is on the 13v tap.

At the transformer the 12v tap reads 11.96v. The 13v tap reads 12.87v. At the spider splice the voltage reads 12.27v, but at the fixtures (I'm measuring from the socket) the voltage reads 12.70 to 12.80v. How come the voltage is higher at the fixtures like this than at the spider splice? Each of the 4 fixtures has a 25' 16ga lead. Am I measuring the voltage at the fixtures right?

Thanks all

JQ

klkanders
08-06-2007, 03:01 PM
I am guessing you had the bulb all the way out when testing at the fixture? If possible try and test with it in.... I am thinking this will solve the problem. Let us know. Good Luck!

johnquest
08-06-2007, 04:04 PM
The fixtures are the single contact bayonet type, so not sure how to measure the voltage with the bulb in. I figured the voltage drop of 16ga cable at 25 feet and one 21w bulb and have been subtracting that from the splice voltage. The fixtures should be at around 11.90 volts. I'll try the 12 v tap too this way.

NightScenes
08-06-2007, 04:52 PM
Just remember, when you take the lamp out, you are removing the load from the wire therefore raising the voltage. Their are many manufactures that sell test leads that allow you to put in a lamp and still check your voltage at the fixture with a full load.

Chris J
08-06-2007, 05:08 PM
Just check the voltage at the hub/spyder, and subtract .5 volts for the fixtures. You should be fine. If you must, you can always stick your probes (make the points really sharp) directly into the fixture wires to check the voltage. I do this on occasion, and then heat the holes to weld them shut.

NightLightingFX
08-07-2007, 12:17 AM
Chris,
I like your idea of sticking your probes through the wire, and then heating up the isulation where you punctured it. I just wanted to confirm however, are you 100% confident that you won't have any wicking problems down the road? I have run into situations-trouble shooting for one, when this technique would simplify everything. I just wanted to confirm how safe this technique is? Thanks for the tip
~Ned:cool2:

Pro-Scapes
08-07-2007, 08:05 AM
forget stabbing the wires... your going to get your fingers as much as the wires themself... your checking voltage not your bloodsugar level right?

Either make or buy the pigtails that allow you to place the bulb in a socket and check voltage on another pigtail while the whole harness is plugged into your fixture... its quick and easy and accurate.

NightLightingFX
08-07-2007, 12:43 PM
Billy,
I like your idea better. Can you help me understand how to make, or buy a pigstail to check the voltage. Thinking this outloud: We need a device to plug into the fixture's socket that in turn allows you to plug in a lamp and also be able to use our probes to measure the voltage. Do I understand right? How do I make or buy this? Thanks
~Ned:dizzy:

Pro-Scapes
08-07-2007, 05:24 PM
hey ned... cast sells one for mr 16 based fixtures I think thier item is mr16test or something like that... Its basically just 2 mr 16 sockets and some pins. You insert the pins into the socket of your fixture... plug a lamp of same wattage into one of the sockets and then your voltmeter into another one.

I been having the idea to make one where I dont have to mess around with cramming my test leads into a socket and make it just plug into my meter.

I recall recently someone mentioned one for S8 and wedge based bulbs... i think Cast has one now or has discussed making one ? Mines rather crude... I snapped the glass off a bad 3156 bulb and soldered some wires on from a new socket to the wires inside the bulb then taped it all up. This gives me the ability to test the voltage under load. Its not pretty but it works. What would be slick is one harness that tested s8 and mr bulbs.

NightLightingFX
08-07-2007, 06:13 PM
Billy,
Thanks for the input. I just ordered an MR16 tester.:weightlifter:
~Ned
www.nightlightingfx.com

klkanders
08-08-2007, 01:33 AM
On MR16's I have lifted the bulb with my tester leads just enuf to expose pins and get probe ends on while lamp is still lit. Works fine on the Kichler 15384 but may not on other fixtures.

JoeyD
08-21-2007, 06:33 PM
HUB SYSTEM: 25ft 16/2 wire leads on every light. Set Voltage at hub between 11.5v and 12.5v. You will lose 1/2v through 25ft of 16/2 putting your lamps btween 11 and 12v.

INTEGRA Bespoke Lighting
08-21-2007, 06:55 PM
Instead of attempting to apply general 'rules of thumb' to voltage issues, why not get yourself a proper, accurate digital tester and test the voltage at each fixture before you make the permanent connection. While you are at it, clamp on an Amp Meter to the wire run and ensure you are not overloading the branch circuit. You will be amazed at how much you learn about wiring circuits up properly by doing this each and every time. Around here we call it "Balancing the Transformer" and it is a MUST on every system.

Have a great day.

Pro-Scapes
08-21-2007, 11:06 PM
James I know you are against the hub. When we balance voltage on a hub we take a reading UNDERLOAD at at least 1 fixture per hub. If we took a reading at the hub only under load we would look for around 11.6 or so. Yes about half a volt drop with the 25 ft leads.

I do agree with James on checking amperage on each branch. Recording this info is a good practice and we do it for every run noting it inside the trans lid including color code... amperage... common number....tap and location of that run (ie. N. Front Porch spots) Knowing your amperage can also help you diagnose the system should there be an issue later. It can help you find the bad run on a breaker with 4 runs on it and such.

JackTorsed
08-24-2007, 10:43 PM
James I know you are against the hub. When we balance voltage on a hub we take a reading UNDERLOAD at at least 1 fixture per hub. If we took a reading at the hub only under load we would look for around 11.6 or so. Yes about half a volt drop with the 25 ft leads.

I do agree with James on checking amperage on each branch. Recording this info is a good practice and we do it for every run noting it inside the trans lid including color code... amperage... common number....tap and location of that run (ie. N. Front Porch spots) Knowing your amperage can also help you diagnose the system should there be an issue later. It can help you find the bad run on a breaker with 4 runs on it and such.

how about the car fuse in the hub. Anyone doing it?

NightLightingFX
08-25-2007, 01:22 PM
My introduction to low voltage lighting was through Unique. The Unique hub system recomends using fuses. I have evolved to where I go to NAPA and buy fuses vs. spending a small fortune through Unique. The fuses really saved my a$$ on a job I did for a hospital's "zen garden" Some lamps burned out premeturely (that is a whole other tangent to go on), and the hospital maintenance guy randomly through in 50W MR16 were I was using 20W lamps. Needless to say some fuses at my hubs were blown, but if I hadn't had those fuses. I could have had some bigger problems. Since my fuses at certain hubs were blown it made trouble shooting a lot easier. I usually don't use fuses on small jobs. However, for large jobs (it can really aid in trouble shooting) and commercial jobs (one more element of professionalism that will separate me everyone else) I will use them.
~Ned
www.nightlightingfx.com

JoeyD
08-25-2007, 03:15 PM
Fusing at the hub is just added protection. I know most of you guys prefer to have your secondary protection at the transformer but having the protection in the hub allows for precise fusing per run vs just fuse protecting commons in which case you could have 3 runs on one common making it harder to figure out. Not all that much harder but when the fuse at the hub pops it is very obvious where the problem is and where to start your troubleshooting.

wbaptist
09-10-2007, 07:07 PM
Here is a diagram of the hub method and the voltages.



http://i139.photobucket.com/albums/q304/rusty51501978/HubMethod.jpg

William Baptist
Unique Lighting Systems

pete scalia
09-10-2007, 08:57 PM
Fusing at the hub is just added protection. I know most of you guys prefer to have your secondary protection at the transformer but having the protection in the hub allows for precise fusing per run vs just fuse protecting commons in which case you could have 3 runs on one common making it harder to figure out. Not all that much harder but when the fuse at the hub pops it is very obvious where the problem is and where to start your troubleshooting.

Does the fuse suffer any damage when the hub fills with irr or rain water?

JoeyD
09-10-2007, 10:12 PM
Does the fuse suffer any damage when the hub fills with irr or rain water?

It could suffer but we use weatherproof greased fuse holders. I am sure some fail but I dont see many get returned. The holder works really well.

Pro-Scapes
09-11-2007, 09:47 AM
joey are you saying to fuse the hub and no secondary in the trans ? I dont think I would like that what if there is a short to common or a short to voltage BEFORE that hub ? (ex. wire gets hit with shovel ext)
Transformers need to protected on the secondary inside the trans. If I used one without I would be installing a fuse in the trans not just the hub.

JoeyD
09-11-2007, 11:09 AM
joey are you saying to fuse the hub and no secondary in the trans ? I dont think I would like that what if there is a short to common or a short to voltage BEFORE that hub ? (ex. wire gets hit with shovel ext)
Transformers need to protected on the secondary inside the trans. If I used one without I would be installing a fuse in the trans not just the hub.

Good question Billy. There are a couple of different ways people are doing this. The problem with secondary fused TF's is the fuse/breaker is tied to the common taps. Dont take the statement the wrong way, seconday fuse protection is better than none and we make those types of units.

The problem with SF TF's is you could run a couple of different runs onto one common so if a short occurs and trips that fuse/breaker you still have to determine which one has the short. SO by putting the fuse inline on each homerun you now individually fuse each secondary run. So what I have done in the past is tie in my inline hub fuses at the transformer on the common side of my home runs. This gives me the same protection like I would have if I put it in the hub but now I can do all my trouble shooting starting right at the transformer and know exactly which run has the issue. So weather you put the inline fuse at the Hub or in the transformer doenst matter all that much. The benefit to both is each run is individually protected. So the ultimate protection would be an inline fuse in your hub and an inline fuse at the transformer. Obviously the second best would be an inline fuse at your Hub and secondary fuse protection ON your commons at the transformer. And the minimum should be inline fuse protection at the Hub.

Bottom Line is PROTECT YOUR RUNS!!!

pete scalia
09-11-2007, 08:50 PM
It takes less than a minute to find the shorted wire inside the trans at the common. You disconnect all and connect one by one. the one that trips the breaker is the one or the one with the sky high amp reading . no brainer.

Chris J
09-11-2007, 10:21 PM
Joey,
Sorry to say it, but he's right. That's what I do, and it seems that it is alot easier then fusing each run/hub for each install. You are only going to encounter this problem on a very, very limited number of occasions anyway.

JoeyD
09-12-2007, 09:13 AM
Believe me I understand that guys. But the question was more along the lines of protecton not neccesarily troubleshooting. Inline fusing just identifies the problem run without having to do that. But I do understand the ease of finding your short by process of elimination.

JoeyD
09-12-2007, 01:03 PM
here is an example of a really trick inline fuse application. You can see how the installer ran a gutter below the 5 I-Force Transformers to house all his inline fusing in. He utilized automotive mini fuse blocks to better protect all his secondary runs individually. I will try to get more pics of this install, very trick!!

JoeyD
09-12-2007, 01:30 PM
The install was actually done at our "test home" by Mike Borgeson, Unique Advanced Installation Instructor. If you guys want more info on it let me know!

trailboss
09-12-2007, 08:15 PM
Sure - I would love to see more detail on this set up.

pete scalia
09-12-2007, 10:46 PM
nice clean work. Kudos.

ChampionLS
09-13-2007, 10:55 PM
Why go through all the trouble to route wiring in a Troth, use conduit, fuse blocks, and hang everything nice and level, and not hardwire the primary side too?? Your never going to remove any of those transformers, so it would neaten everything up.

What is the purpose of all that work? Unless this is a installation at a Golf Course, where secondary lines could possibly get cut from a core airator, or someone likes to do mass plantings in their beds every season, when or how often (if ever) is there going to be a short?

Chris J
09-13-2007, 11:50 PM
I don't know if it's the case with these transformers, but some manufacturers will void the warranty if you cut the plug off. Also, the installer may not be a licensed electrician, thereby prohibiting him from doing this. I think the install is top notch. It's not something that I would do (personally) but I think it looks very professional, and I'm not about to criticize anything about this set-up! If more of us would take the time to "pay attention to detail" like this, our industry would be all the better for it.:clapping:

pete scalia
09-14-2007, 12:46 AM
I don't know if it's the case with these transformers, but some manufacturers will void the warranty if you cut the plug off. Also, the installer may not be a licensed electrician, thereby prohibiting him from doing this. I think the install is top notch. It's not something that I would do (personally) but I think it looks very professional, and I'm not about to criticize anything about this set-up! If more of us would take the time to "pay attention to detail" like this, our industry would be all the better for it.:clapping:

which transformer manufacturer/s void the warranty for cutting off the power plug and hard wiring it?

Chris J
09-14-2007, 12:54 AM
Any of them that are UL listed.

pete scalia
09-14-2007, 12:57 AM
Any of them that are UL listed.

Which manufacturer/s specifically?

Chris J
09-14-2007, 01:16 AM
Pete,
You remind me of my wife, very persistant.
As I have always understood it (but I could be wrong) if you cut the plug off of a transformer, you are undermining the UL1838 standards for LV transformers and any manufacturer that abides by these standards will not warranty the product if you do this. I will not call out any specific manufacturer at this time, so your are just sh!^ out of luck. I suggest you contact your manufacturer of choice and ask them if they will warranty their product if you hack up their transformer. Fair?

Lite4
09-14-2007, 01:19 AM
Pete,
I have removed the plug on my Vista transformers and hard wired directly into the line voltage side. Wasn't a big deal. Their cord is just a pig tail wired into the same lugs anyway.

pete scalia
09-14-2007, 01:24 AM
Pete,
You remind me of my wife, very persistant.
As I have always understood it (but I could be wrong) if you cut the plug off of a transformer, you are undermining the UL1838 standards for LV transformers and any manufacturer that abides by these standards will not warranty the product if you do this. I will not call out any specific manufacturer at this time, so your are just sh!^ out of luck. I suggest you contact your manufacturer of choice and ask them if they will warranty their product if you hack up their transformer. Fair?

I hardwire vistas transformers all the time, have sent a few in for warranty and have never been rejected. I don't like it when false information is spread as fact and then when you call a guy on it he gets all pissy and tries to make you out to be a hump for questioning him. Instead of admitting they made a mistake and were talking out of their a%* in the first place.

Lite4
09-14-2007, 01:45 AM
I also have never had a prob with Vista taking their trannys back in on warranty. The only gripe I have with the Vista Trans is the lug size. If your working with 2-3 12s, hey no prob. If you got to jam an 8 in their somewhere your SOL (sorry out of luck). I hope someone from Vista reads this. I have threatened to swith brands.

pete scalia
09-14-2007, 02:00 AM
I also have never had a prob with Vista taking their trannys back in on warranty. The only gripe I have with the Vista Trans is the lug size. If your working with 2-3 12s, hey no prob. If you got to jam an 8 in their somewhere your SOL (sorry out of luck). I hope someone from Vista reads this. I have threatened to swith brands.

They are supposed to be making their own transformers in house soon. Maybe they will upgrade the lugs.

Chris J
09-14-2007, 02:04 AM
I hardwire vistas transformers all the time, have sent a few in for warranty and have never been rejected. I don't like it when false information is spread as fact and then when you call a guy on it he gets all pissy and tries to make you out to be a hump for questioning him. Instead of admitting they made a mistake and were talking out of their a%* in the first place.

OK now you're just getting on my nerves. First of all, are you a licensed electrician? No? Then you have no business in the j-box in the first place. Secondly, I have not spread any false info. What I have stated is fact until proven false (which has not been yet by an authority). Just because Vista takes the transformer back, does not mean that all manufacturers will. As I stated in my previous post, this is information that I was "recalling" from the past. I'm quite sure if I look into it further, the NEC, UL and SEVERAL MANUFACTURERS will back me up. You should cover yourself before you make foolish statements like the one above my son.

Lite4
09-14-2007, 02:08 AM
They are supposed to be making their own transformers in house soon. Maybe they will upgrade the lugs.

Yeah, I talked to Laurel from Vista in our neck of the woods and he had mentioned that very thing. He said the lug size was one of the main issues they were going to address in the new tranny.

Chris J
09-14-2007, 02:17 AM
Hey Pete,
Could you private message me. I'd like to talk to you in private.

JoeyD
09-14-2007, 09:36 AM
Why go through all the trouble to route wiring in a Troth, use conduit, fuse blocks, and hang everything nice and level, and not hardwire the primary side too?? Your never going to remove any of those transformers, so it would neaten everything up.

What is the purpose of all that work? Unless this is a installation at a Golf Course, where secondary lines could possibly get cut from a core airator, or someone likes to do mass plantings in their beds every season, when or how often (if ever) is there going to be a short?


Actually this property will have plantings going on every season so shorts are a concern due to frequent gardening and this is only one run of transformers. Tehre are a lot of lights on this job. Nate really wanted us to be able to show people a different way of doing things and how well you really could protect a system with it being organized and easy to service down the line. At minimum it sure does look cool I think!

JoeyD
09-14-2007, 09:41 AM
In regards to cut power cords. We will still warranty our units if the power cord is cut but we will not replace the cord with a new one like we did in the past.

As far as being a liscensed electrician to install that 5 TF gutter set up.....You only need to be a liscensed electrician to run the 120v power and put in the 4 gang outlets. As far as running all the fusing, you guys that are liscensed low volt installers can do that install without any problems.

ChampionLS
09-14-2007, 12:46 PM
It does look neat, and especially with all those secondaries, it's a better way to manage it. It was a little overkill to not hardwire the transformers in since everything else is in conduit This appears to be a very large install.

David Gretzmier
09-15-2007, 12:49 AM
maybe I'm mising something here, but two things. one- If you cut off a cord and wire direct, you are playing electrician. not allowed in my state. forget waranty, If I get caught doing that , 5000 dollar fine. two, as pretty as that install picture is, I thought the whole point of multiple transformers was to get the trans closer to the lights. thus you mount one in the front of house, another at the side, another at the back, etc.

sure you can go to the higher voltage taps to go further away, but you are using more wire and having to go under drives and walks when you could set a trans closer to the lights. more wire, more sleeving, more labor, all of which means more money for the same lighting effect ,just to have a real slick looking bank of trans?

I love the way it looks, and I am sure it impresses the ladies, but am I the only one who would do this differently?

pete scalia
09-15-2007, 01:06 AM
It's irresponsible to state that one can hardwire a transformer with a low voltage lighting license (I never heard of this license but I'd like to get one if my state offered it). Codes vary state to state not only that some people are spastic and can't even make a tight low voltage connection let alone a 120v one.

ar-t
09-15-2007, 12:11 PM
How many of you guys are licensed electricians? I bet the answer is zero. If you were, you wouldn't just cut the cord, and hardwire it in. You would remove the SJ cordage, use the approved wire, run it in flexible conduit.

As for conduit..........thinking it only protects against (secondary) shorts is a bit........(bad pun alert).......short sighted. Nope, just cut wires. Happens all the time when landscapers are futzing in the beds. They are never working in the beds when voltage is present, so there won't be a short.

The lights won't work either.....after they are gone. I learned the hard way. All installs now use conduit and "perma posts". Never had a call-back about landscaper damage since I started doing that.

(Also helps some against corrosion.)

JoeyD
09-15-2007, 02:45 PM
maybe I'm mising something here, but two things. one- If you cut off a cord and wire direct, you are playing electrician. not allowed in my state. forget waranty, If I get caught doing that , 5000 dollar fine. two, as pretty as that install picture is, I thought the whole point of multiple transformers was to get the trans closer to the lights. thus you mount one in the front of house, another at the side, another at the back, etc.

sure you can go to the higher voltage taps to go further away, but you are using more wire and having to go under drives and walks when you could set a trans closer to the lights. more wire, more sleeving, more labor, all of which means more money for the same lighting effect ,just to have a real slick looking bank of trans?

I love the way it looks, and I am sure it impresses the ladies, but am I the only one who would do this differently?

All those transofrmers are powering lights up in a backyard. The furthest light is 300ft away. Having the freedom to put your transformers all in one location makes maintenance very easy and eliminates thenead for units spread all over. T

There is a whole nother bank of transformers for the front yard. This job has over 200 lights and will end up closer to 300 when finished.

Chris J
09-15-2007, 10:09 PM
How many of you guys are licensed electricians? I bet the answer is zero. If you were, you wouldn't just cut the cord, and hardwire it in. You would remove the SJ cordage, use the approved wire, run it in flexible conduit.

As for conduit..........thinking it only protects against (secondary) shorts is a bit........(bad pun alert).......short sighted. Nope, just cut wires. Happens all the time when landscapers are futzing in the beds. They are never working in the beds when voltage is present, so there won't be a short.

The lights won't work either.....after they are gone. I learned the hard way. All installs now use conduit and "perma posts". Never had a call-back about landscaper damage since I started doing that.

(Also helps some against corrosion.)

You would be wrong. Some of the LV folks on this forum are, in fact, licensed electricians. Not many though, and that is why most of them should not be cutting off any 120v cords and hard wiring. This is just another perfect example of professionalism vs. non-professionalism. The contractor who practices this without a license is not only jeopardizing his client's home, he is also jeopardizing his business and his family's income.

David Gretzmier
09-15-2007, 11:28 PM
300 lights. wow. I am trying to imagine what this house looks like. but with enough trees, I guess 300 lights at one location can make sense. That job is out of my league.

ar-t
09-16-2007, 01:46 AM
You would be wrong. Some of the LV folks on this forum are, in fact, licensed electricians. Not many though........

All of the licensed electricians that I know only install mercury vapour (it costs a lot more......) and they look down their nose at the LV crowd. Yes, there are probably exceptions. But, it comes down to the mighty $$$$$$, and HID is more expensive. So, they only do that.

Still, the point stands: a licensed electrician would know not to hardwire 16 ga portable cordage to 15A circuit. And put it in a conduit.

pete scalia
09-16-2007, 11:52 AM
You would be wrong. Some of the LV folks on this forum are, in fact, licensed electricians. Not many though, and that is why most of them should not be cutting off any 120v cords and hard wiring. This is just another perfect example of professionalism vs. non-professionalism. The contractor who practices this without a license is not only jeopardizing his client's home, he is also jeopardizing his business and his family's income.

"The sky is falling! The sky is falling!" -Henny penny

pete scalia
09-16-2007, 12:03 PM
How many of you guys are licensed electricians? I bet the answer is zero. If you were, you wouldn't just cut the cord, and hardwire it in. You would remove the SJ cordage, use the approved wire, run it in flexible conduit.

As for conduit..........thinking it only protects against (secondary) shorts is a bit........(bad pun alert).......short sighted. Nope, just cut wires. Happens all the time when landscapers are futzing in the beds. They are never working in the beds when voltage is present, so there won't be a short.

The lights won't work either.....after they are gone. I learned the hard way. All installs now use conduit and "perma posts". Never had a call-back about landscaper damage since I started doing that.

(Also helps some against corrosion.)

Some transformers are built so you can't hardwire them by removing the cord and running conduit to them so the only choice you have is to cut the cord. It beats getting calls for tripped GFI's