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Mike M
11-28-2008, 04:54 PM
Chaining is no problem, but I had some problems experimenting with looping at my own house.

Apparently, the LED or driver/control module acts as a sort of resistor, and you lose voltage rapidly.

If someone could explain this more scientifically I'd appreciate it.

This is bizarre: on one circuit, using 14 gauge wire, I had looped (2) 4.5 watt LED's, and a 20w path. The LED's were fine, but the path was not even glowing, even with the meter reading 12v at the socket. Is the meter giving me misleading voltages because of the loop (i.e., one phase is 12v, the other much lower?) I replaced the bulb, checked connections, switched paths, etc., same problem.

irrig8r
11-29-2008, 01:42 AM
I'm interested, but I have no clue.

Wish I could help.

The Lighting Geek
11-29-2008, 11:37 AM
I am not sure I understand what you mean by loop. Could you draw diagram of how you are wiring and maybe I can help.

Mike M
11-29-2008, 02:11 PM
One wire is spliced into the first lead of the fixture, the second lead from that fixture is spliced to a wire that goes to the next fixture. And so on.

There is one wire that runs unspliced until after the last fixture.

In effect, it's like one long wire making a loop back to the transformer.

......./\.........../\........

...............................

The Lighting Geek
11-29-2008, 04:40 PM
Ok, I am reaching back into the memory banks here....
I believe we wire fixtures in parallel, but what you are referring to a loop method here is actually wired in series. It does make a difference. In simple terms, LEDs require a transistor to reduce the voltage to the specified amount rated for the LED, many are 1.5-3.0 volts. The circuitry needed to operate between, say, 8-15 volts is much more complicated. Also they need a diode to convert them to DC because we are using AC transformers. This may be what is causing the results you are getting. I know that wiring LED circuits in series can increase the impedance or resistance but not change the voltage. Hopefully someone will correct me if I am wrong here. :) Why not just wire them in parallel or daisy chain? Or better yet use the hub method so you have same voltage at each fixture?

Mike M
11-29-2008, 05:42 PM
Yes to all the above. I just wanted to post that looping is not an option for LED's, as I confirmed in my yard.

It's really weird how I was getting a reading of 12v at the path, but he bulb was hardly glowing. My guess is the meter was getting the 12v from only 1/2 of the A/C cycle.

Pro-Scapes
12-05-2008, 06:37 PM
am i off my rocker with a frozen brain or wouldnt a standard chain be called series/parallel.

What your doing in series mike or the "loop" as you call it will have the christmas light syndrom. Rememeber when you used to yank a bulb out and the whole string would go dead ? Also... a loop is a run of main wire that is fed from the transformer at both ends. This is why.

Think of it like this

Voltage is pressure (like water pressure)
Amps is the flow.

When you connect lights in series your forcing your power to flow thru multiple restrictions(resistance) at each light. When you wire in series parrallel(chain) or parrallel your amperage can flow down your main line as well as up into each fixture. I think it also has to do with how the LED drivers or rectifiers alter the power ???

You should not be wiring anythnig in series when it comes to lighting. To clarify this for thoes who did not get it. Series would be cutting only a singular wire of your 2 conductors and attaching your fixture leads to each ends of the cut.

INTEGRA Bespoke Lighting
12-05-2008, 08:36 PM
Billy has it right there Mike.

Mike M
12-05-2008, 08:38 PM
Yes, Billy, but it is called the loop method in lighting. It works with halo's but the LED's frig it up.

Chris J
12-05-2008, 09:05 PM
Wow, I'm learning something new today. My understanding of a standard loop has always been to attach the fixtures using both conductors as usual, but re-connect the end of the run either at the transformer or before the first fixture. You guys are talking about something I've never heard of before, but then again I'm not an electrician. Please continue with this info.

irrig8r
12-05-2008, 10:32 PM
The only "loop" method Ive heard of in lighting is running your home run in one long loop back to the transformer, but still wiring fixtures in parallel fashion.

I've encountered it on existing lighting jobs, but never saw any advantage to it. It might "balance" the voltage load so you get less voltage drop from one end to the other, but more voltage drop overall (can we call that method "Uniformity Of Dimness" ?) and more cable costs.

Pro-Scapes
12-05-2008, 11:21 PM
A loop is what your saying Chris and Gregg. Here i am now going to call it the "landscaper special" method. I have even seen a loop connect to different transformers at each end.

Usually the wire is severly overloaded and oxidized. It can often be hallmarked by regular wire nuts and electrical tape or pierce points.

Mike what your talking about is NOT a loop. Your thinking a single conductor loop. A loop would have a piece of wire connected to voltage and common at one end.... a number of fixtures attached like a daisy chain then the other end of the cable is again attached to voltage and common being sure to maintain polarity. What your making is in a way a loop but its a series connection and a big no no. If you were to do it with halogens and you get one lamp failure kiss the whole circuit good bye.

Think of it like this. Do you REALLY want 10 amps flowing up into your socket and back out again ? Talk about a fuseable link!

Pro-Scapes
12-05-2008, 11:57 PM
Yes, Billy, but it is called the loop method in lighting. It works with halo's but the LED's frig it up.

Wire it up with halogens like your saying mike... about 8 fixtures 20 w each and tell me what you see... then I want you to put a bad lamp in fixture number one and tell me what you dont see... never mind the v drop because the system wont be lasting that long once thoes socket wires heat up.

If you have ANY systems out there wired like your mentioning I would be grabbing a box of ace connectors and going to fix it asap. A loop or even a daisy chain is better than a series wiring. BOTH conductors MUST be connected to all fixtures. I dont care if you end up with 9v. Its still better than your series!

I have not tried this but I also think with enough fixtures you could pop a lamp like a fuse because your forcing the current thru the filament instead of just allowing the lamp to draw the intended power.

Mike M
12-06-2008, 08:05 AM
Billy, you are spot on.

I'd like to hear Paul's take on this, since he's said he has utilized the loop method in the past where it was beneficial.

Chris J
12-06-2008, 09:41 AM
I'm pretty sure Paul will tell you his idea of a loop is what I mentioned above: connecting both conductors but pulling the end of the run back to the source before the first fixture (or to the trans).

Pro-Scapes
12-07-2008, 07:54 AM
If you pull it back to the source before the first fixture is it not then a lollipop ? Back to the trans is a loop.

Mike i think just about everyone will be in agreement. What your talking about is NOT a loop it is a series connection and doomed to fail.

Each and every lamp or led fixture becomes a resistor and if you have a anything inside that led that modifies the power such as a recifier your gonna have issues. Im no rocket scientist but I think you may even damage your led's if you added enough of them.

Chris J
12-07-2008, 09:34 AM
If you pull it back to the source before the first fixture is it not then a lollipop ? Back to the trans is a loop.


This is true Billy, but wouldn't the results be exactly the same? I've never tested this, but maybe I should just for informational purposes.

Mike M
12-07-2008, 09:59 AM
I agree with you, Billy. It explains why I had mixed results experimenting with this at my own property.

Where is Paul? Someone go get him.

Pro-Scapes
12-07-2008, 10:51 AM
Well i think it would depend on the layout and the total load Chris wouldnt it ? Im trying to run a scenario in my head about it. I do a hybrid T hub sometimes for long pathways where I run a 10ga out to the middle of a 12ga then place a hub with 2 or 3 lights on each end. This works well when you have a long path. As long as you control your voltage there are a ton of ways in which to wire things.

I garuntee you could take identical designs and 3 guys who know what they are doing and get 3 different wiring scenarios that work.

Mike something I do aplaud is your desire to learn at your own home and experiment there before you go doing hairbrained things like this for a client.

I think its safe to say Paul will not have much different to say than Chris and I have already told you and James confirmed.

NightScenes
12-12-2008, 03:30 PM
Billy is right on here. If you are going to use a loop method, you must maintain polarity but wire in parallel. What you were describing Mike was a series method and that will not work with LED because of the drivers.

Mike M
12-12-2008, 07:35 PM
Paul, could you describe the particular details of a loop set-up? What exactly goes where. Tanks.

NightScenes
12-12-2008, 08:33 PM
Mike, the wire has a ribbed side and a smooth side, it is very important to always attach the ribbed side to the ribbed side and smooth to smooth, this will maintain polarity. This goes all the way back to the transformer. At each fixture, the connection needs to be smooth/smooth and ribbed/ribbed along with the two leads from the fixture. Polarity doesn't matter on the fixture leads however.

By attaching both "ends" of the wire to the transformer you are feeding the loop from both ends. This can even create a half volt increment by placing one end (say it's the smooth wire) on the 12v tap and the other end of the wire on the 13v tap. This is like having a 12.5v tap.

One bad thing about using the loop is that it uses so much more wire. I only use this method when placing a lot of low wattage fixtures on a deck. It allows for even voltage and I'm hooking up a lot of lights on one run.

I hope this helps.

Mike M
12-13-2008, 06:57 AM
Cool. Thanks, Paul. One question out of curiosity, what about the ends, does one ribbed wire go into the common, and then the other ribbed go into the tap, and vice-versa?

The reason I was exploring with the LED wire configurations was to see if I could pull off a single wire loop. I found the solid wire 14 gauge to be awesome to work with (twist-ons are much more effective with solid, also, wiring to the trans is so much easier, too). It would also make automatic wire-trenchers easy to use.

Using two solid wires, however, gets to be like a slinky on steroids.

I'm not trying to re-invent the wheel, but with LED's, who knows what we can do to improve our configurations and reduce excess.

Pro-Scapes
12-13-2008, 07:26 AM
Cool. Thanks, Paul. One question out of curiosity, what about the ends, does one ribbed wire go into the common, and then the other ribbed go into the tap, and vice-versa?

.


Mike... please get a video camera and do this for us and place it on you tube. We can file it under "hey yall watch this"

Seriously... Make sure you got a secondary fuse or breaker... make up a small 1 fixture loop and show us what happens (or doesnt happen or shouldnt happen) when you cross polarity :) Polarity is everything in a loop. I would see no benifit in it with led's

Mike M
12-13-2008, 09:26 AM
I find no humor in giving my life for your amusement. On the other hand, some minor burns and property damage might be worth the you tube fame.

Billy, I don't want to use that method, I'm just curious how exactly it's wired. Like Paul says, it sounds like wire overkill for most applications.

I assume by your comments that you wire both ends of the common to the common terminals, and both ends of the other wire to (2) of the taps.

My next question, if my truck needs a jump start on a job, can I use a transformer? If so, how do I go from AC to DC and how far away from everything should spectators be standing?

NightScenes
12-13-2008, 09:26 AM
Mike!!!! DO NOT and I repeat, DO NOT put one ribbed end under the common and the other ribbed end under the 12,13,14,15, etc taps!!!! Both ribbed or both smooth would go under either the common or secondary voltage tap!! If you put one ribbed and one smooth, from the same set of wires, under the same tap, things go BOOM!!!!!!!!!!!!!!!!!! This is called a DIRECT SHORT!! If your first end of the smooth wire is under the common, your other end of that wire MUST be under the common as well.

Mike M
12-13-2008, 09:31 AM
Thank you, Paul. I appreciate your warnings and concern for my well-being, not like Billy, who wants me to blow my face off in front of the world.

irrig8r
12-13-2008, 10:16 AM
Cool. Thanks, Paul. One question out of curiosity, what about the ends, does one ribbed wire go into the common, and then the other ribbed go into the tap, and vice-versa?

The reason I was exploring with the LED wire configurations was to see if I could pull off a single wire loop. I found the solid wire 14 gauge to be awesome to work with (twist-ons are much more effective with solid, also, wiring to the trans is so much easier, too). It would also make automatic wire-trenchers easy to use.

Using two solid wires, however, gets to be like a slinky on steroids.

I'm not trying to re-invent the wheel, but with LED's, who knows what we can do to improve our configurations and reduce excess.

One wire of the pair will always be the common. The other will always be the hot. That's one reason why they are distinguishable with either ribbing or printed white lettering (depending on the brand.)

Do it otherwise, and film the process, and we will all be entertained, but you will not be happy.

As a sidenote, I used to hear that stranded wire was better than solid for low voltage because (in theory) the greater surface area of individual strands somehow allowed electrons to pass more easily, with less resistance resulting in less voltage drop.

I never actually experimented with this, but now I hear that it was a myth all along and the reason to use solid wire is that it is easier to work with (easier to flatten out).

irrig8r
12-13-2008, 10:31 AM
Too late for editing the above... I meant the reason to use STRANDED wire was that it's easier to work with.

As you know, SOLID wire has sort of a memory, and doesn't want to lay down flat in a trench.

Mike M
12-13-2008, 11:01 AM
Gregg,

You are correct about the wire, as Joey confirmed, the only difference is how it has no memory. But solid wire is more durable, and a lot faster and more reliable in smaller gauges for splicing with wire nuts.

They should at least consider putting solid wire on the leads of the LED fixtures instead of those cheap, little, breakable, tedious to strip and put wire nuts on, 18 gauge stranded wires. This is another reason I like Unique and Cast 25' leads.

Pro-Scapes
12-14-2008, 08:50 AM
Gregg,

You are correct about the wire, as Joey confirmed, the only difference is how it has no memory. But solid wire is more durable, and a lot faster and more reliable in smaller gauges for splicing with wire nuts.

They should at least consider putting solid wire on the leads of the LED fixtures instead of those cheap, little, breakable, tedious to strip and put wire nuts on, 18 gauge stranded wires. This is another reason I like Unique and Cast 25' leads.

Stop using wire nuts and you wouldnt have this problem. What happened to solder and or crimps ? Ace connectors... we all know you have a stock pile of splicing stuff at your house that would rival any major manu :laugh:

I didnt want you to get hurt and thats why the sarcasim in my post. I would hope your using some kind of secondary protection which should IMEDIATLY trip with a direct short.

Just kidding. Get the idea alligator type strippers and the 18ga leads are easy to strip. Solid core in that small diameter gets fragile

Mike M
12-14-2008, 09:29 AM
Solid core in that small diameter gets fragile

No it doesn't.

Billy, I solder at my hubs and use ace for extensions, but I am just complaining about those crappy leads that many manu's use. Small stranded wire sucks, especially for twist-ons. I don't use that stuff, but my Kichler sample LED has the small wire lead. So I guess what you are saying is I should plan to use those Hadco pierce points when working with the LED's so I don't have to use nuts. They are made for #12 to #18.

I do, I admit, use twist-ons for some service calls on pre-existing cut and nut systems. Personally, I wish I was established enough to turn down service work on anything but my own systems, for liability/accountability issues.

Speaking of connectors, I still want to get a pack of those solder/heat shrinks that James was talking about for leads.

Pro-Scapes
12-14-2008, 09:58 AM
I find ace connectors to be outstanding for repairs in cut cables. They add the needed inch or 2 required to make the splice. I have used them to repair everything from cut dog fences and irrigation wire to low voltage cables.

I just wish they were not so expensive!

Mike M
12-14-2008, 12:27 PM
Billy, what about those solder/heatshrink connections? Have you priced those?

NightLightingFX
12-14-2008, 01:34 PM
You can't argue about the quality of splice the ace connectors make. I use them sometimes but most of the time I use www.suresplice.com with a 4-way crimper.

The problem with the ace connectors is that they are expensive and kind of labor intensive - heat srinking & hex screws are a real hassle. The 4-crimper with www.suresplice.com is easy and quick.
~Ned

Pro-Scapes
12-14-2008, 09:43 PM
I do use alot of suresplice tubes. I usually just save the crimps. I do carry a buchanan crimper (the 4 way deal) but dont use it much. I used the sure splice tubes when I solder.

The ace connectors are the bomb when a low profile inline splice is needed such as gazebos and in trees. Orange grease tubes dangeling in trees look tacky.

NightLightingFX
12-15-2008, 03:06 PM
I do use alot of suresplice tubes. I usually just save the crimps. I do carry a buchanan crimper (the 4 way deal) but dont use it much. I used the sure splice tubes when I solder. I'am not challenging, you just curious as to why you prefer soldering. A 4 way crimp is REALLY solid/secure, and it is pretty easy.
The ace connectors are the bomb when a low profile inline splice is needed such as gazebos and in trees. Orange grease tubes dangeling in trees look tacky. I totally agree with you

~Ned

Pro-Scapes
12-15-2008, 04:58 PM
Personal prefference I guess. Soldering is permanant. Things can go wrong with a crimp. Also when I dip my wires in flux it seals up the jacket area as well (i use a pure flux not the cast flux)

Mike M
12-16-2008, 06:01 AM
Billy, what the flux are you talking about??

Please, elaborate on the product you use.

Also, you might add that soldering has to be the fastest method, too.

Pro-Scapes
12-16-2008, 07:26 AM
I know people whine about having to tote that tray around to each connection but really it doesnt take as long as an ACE connection. Im not always into the fastest way if I am more confident in it I will take extra time and effort.

Im not sure on the brand of the flux mike but it comes in quart bottles and I get it at my local electronics supply store. Make sure you seal the container well because not only is it stickier than the flux that come with the cast kit but when it evaporated when you let it sit for some time it will become like Jello.

irrig8r
12-16-2008, 10:16 AM
I've had the opposite problem with flux: bought it as a paste, sat around in my toolbox and melted in the summer and oozed over everything.

Electric shop was my favorite elective in jr. high school. I got pretty good at soldering. And although it can be considered permanent, it's easier (and less costly) to take back apart than an Ace connector should you ever need to. :)

Pro-Scapes
12-16-2008, 04:57 PM
Gregg have you ever seen the solder pots ? You dunk the connection in liquid flux then dunk it in a small pot of melted solder.

I would never think about trying to take one apart. I guess I could if I heated it up or redunked it long enough. Snip snip and resolder if you have to add in a wire. About like the Ace you gotta just cut that sucker apart.

irrig8r
12-16-2008, 09:40 PM
Gregg have you ever seen the solder pots ? You dunk the connection in liquid flux then dunk it in a small pot of melted solder.

I would never think about trying to take one apart. I guess I could if I heated it up or redunked it long enough. Snip snip and resolder if you have to add in a wire. About like the Ace you gotta just cut that sucker apart.

I've actually never seen a solder pot, just pictures.

The soldering I've done in the field has mostly been on the PC boards of a sprinkler controller where there was a broken connection.

My Weller soldering iron worked just fine in those cases.

LightYourNight
12-17-2008, 02:07 AM
Mike... please get a video camera and do this for us and place it on you tube. We can file it under "hey yall watch this"


I think I found that youtube video!!!!

http://www.youtube.com/watch?v=X3HSq3Nz_ik

Mike M
12-17-2008, 04:04 AM
Now, that's a great lighting effect!:clapping:

INTEGRA Bespoke Lighting
12-17-2008, 07:01 AM
I think I found that youtube video!!!!

http://www.youtube.com/watch?v=X3HSq3Nz_ik

See what can happen when you use unlisted transformers? :nono:

or install lighting systems above 15V! :laugh:



(That was an attempt at humour... just in case you didn't get it.)

Pro-Scapes
12-17-2008, 10:20 PM
No thats what happens when you get hacks installing things. I find it HARD to imagine some of these big box store units are listed.

JoeyD
12-18-2008, 11:44 AM
Thats a 22,000 Volt Transformer just to be clear..Not 22v....LOL I can see our competition now! That will be the next thing that gets sent out!
Thats why I hold this multi milion dollar house fire in Minnesota in my pocket......in case anyone wants to argue that UL1838 units can burn down a house!!! In the wrong hands 12v or 50,000v can be dangerous!

Chris J
12-20-2008, 01:53 AM
What? the freak are you talking about Jokeie? Are you trying to insinuate that those fires were created by 1838 systems? Please tell me you are just drinking tonight, and that's a false claiim.