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High Performance Lighting
03-15-2007, 10:26 PM
What is your criteria for choosing the one you use? In other words what features are important to you?

seolatlanta
03-15-2007, 11:04 PM
I would say-

Plenty of room to work and the ability to hardwire. Also room for timer or module.

Dave

High Performance Lighting
03-15-2007, 11:19 PM
what about performance?

NightScenes
03-16-2007, 07:37 AM
I would say that I want a toroidal type transformer as opposed to an EI type for performance. I want circuit breakers instead of fuses (I still don't see why some companies still use fuses). Give me large lugs. I want to be able to put more than a couple of wires into the lug. Forget hard wire transformers. Room to work, I still think that even the best transformers could use an extra couple of inches. Of course, plug-in photo control and timer. I like the convenience of just by-passing the photo control and pulling the timer if I like.

Pro-Scapes
03-16-2007, 11:06 AM
ditto everything paul said plus it must be entirely stainless... must not leak water etc. Some of the MDL knock offs out there rust at the hinges (they have a hinged door with latch) and I dont like the door that they use. Water could still seep in if the bottom of the trans isnt kicked out just a bit more than the top.

Just had a chance to look at the unique inverted transformers which might be a bit easier to work in.

It has to perform and it has to perform reliably. If I could change something about the MDL units I use now it would definatly be more room to work and perhaps if possible space the terminals out a bit more. Even with the drop downs it can be aggrivating to get 4 10 ga wires in a common then 3 in the next. The lugs hold it well but trying to get in there :hammerhead:

Eden Lights
03-17-2007, 11:25 PM
Requirements:
* Large secondary connection lugs for a lot of wires
*As much room as possible under the lugs and bottom plate.
*1 1/4" or bigger bottom plate conduit outlet
*Steady and consistent voltage from small load right up to 100% Capacity. Nobody wants to rewire every tap if you do a little add on. (Tordials)
*Hinged Door or easy access.
*Should meet 1838 Water sprinkler requirements.
*Room for various large control modules. (Timers)
*Easy place to check amps on the primary side.
*Secondary lug screws should stand up to the test of time, no seizing, rusting, and or rounding off of a small lug head.
* No sharp edges
* Rust proof

Things that are nice:
* Angled Secondary Lugs
* Magnetically held open door
* Relayed and Non Relayed Control module plug (Timer) Dimmed circuits need non relayed and relayed units are great for control module life.
* Split Controls with one transformer.
* Extra common tap for balancing loads.

Future Wants:
*Adjustable Automatic secondary voltage regulation

High Performance Lighting
03-18-2007, 12:15 AM
Eden says-Future Wants:
*Adjustable Automatic secondary voltage regulation


I have asked for this feature and am yet to get anyone to bite. It goes like this. Imagine a cable run that is carrying a 105 watt load (3-35watt lamps)with 10 gauge cable or even 12 . The first light is 100 feet from the transformer the other 2 are 10 feet apart or so. You have 11.5V at homerun (first fixture)You get one lamp that goes out and you have more than 12 volts at the remaining 2 lamps. You'd better replace that lamp soon. I want a device that will stabilize voltage going to those remaining 2 lamps. I'm not interested in the RSL device built into the fixture stake. I'm talking a feature built into the transformer that will last.

I hear talk in here about torroidal transformers holding up better under load. Don't talk to me about energy efficiency. I need RAW POWER. I have tested 2 models from different manufacturers so far and I have found the results disappointing. They do run cooler, however the voltage drop is much greater than the super duty coil and core transformer that I am using now on both units I tested. The torroidal one I just tested last week had 119V input voltage 12.2V,13.2V,14.2V,15.2V with no load at the secondary taps. So far so good but When I put a 160 watt load (split over 2 cable runs, 5-20 watt lamps with the home run center fed to the middle fixture 30 ft from transformer 10 feet of cable between the remaining two fixtures on both sides of the homerun fixture, run 2 had 50 feet to homerun fixture and approximately 10 feet between the other two fixtures) so this was not a heavy load by any means I lost 1.1 full volts across all temrinals-11.1V,12.1V,13.1V,14.1V respectively. This to me is not acceptable. Fully loaded this transformer will lose a full 2 volts or more- No Good. It was only a 300 watt transformer. I have a 600 watt transformer from this same manufacturer so far I am yet to put a load on it to check performance. I did check it's output unloaded again with a 119V incoming line voltage. I was shocked to find this unit had even less power registering an anemic 11.6V,12.6V,13.6V,14.6V. The only redeeming value I found was the tight regulation between voltage taps -an exact 1 volt difference. When I pulled the unit apart to examine the torroidal core it appeared to me that it was wound with 14 gauge copper. The manufacturer told me explicity that they use the "heaviest copper windings". I guess he didn't expect me to tear the thing apart and expose the "wizard behind the screen". Anyway talk to me tell me what kind of drop you are experiencing with your transformers. I am very very happy with my current set up but if there is something better out there I need it.

Eden Lights
03-18-2007, 12:29 AM
I have asked for this feature and am yet to get anyone to bite. It goes like this. Imagine a cable run that is carrying a 105 watt load (3-35watt lamps)with 10 gauge cable or even 12 . The first light is 100 feet from the transformer the other 2 are 10 feet apart or so. You have 11.5V at homerun (first fixture)You get one lamp that goes out and you have more than 12 volts at the remaining 2 lamps. You'd better replace that lamp soon. I want a device that will stabilize voltage going to those remaining 2 lamps. I'm not interested in the RSL device built into the fixture stake. I'm talking a feature built into the transformer that will last.

I tried to get more information about this technology about a year ago, but the local IRIS rep. was lost.

http://www.iris-lighting.com/common/CLDetail.cfm?id=14167&CFID=4011961&CFTOKEN=76750466

Eden Lights
03-18-2007, 12:41 AM
We have been using the Kichler Pro and Contractor series along with FX units on dimmed circuits and we have not had a problem with voltage drop increasing as we reach capacity in a couple of years. I wont try to make a broad statement about MDL made units, but I thought 900W+ units had already gone to Tordials and the rest would soon follow?? I tried to keep up on this but I gave up. I have not lab tested the two so I don't know, but Cast did and the results can be seen on their website.

We did get smoked on primary voltage increases on two large jobs last year. Both jobs were installed on properties with overloaded and failing cans that were replaced after our install. We had to rewire all the transformers and change a lot of lamps way too early.

High Performance Lighting
03-18-2007, 12:51 AM
We have been using the Kichler Pro and Contractor series along with FX units on dimmed circuits and we have not had a problem with voltage drop increasing as we reach capacity in a couple of years. I wont try to make a broad statement about MDL made units, but I thought 900W+ units had already gone to Tordials and the rest would soon follow?? I tried to keep up on this but I gave up. I have not lab tested the two so I don't know, but Cast did and the results can be seen on their website.

We did get smoked on primary voltage increases on two large jobs last year. Both jobs were installed on properties with overloaded and failing cans that were replaced after our install. We had to rewire all the transformers and change a lot of lamps way too early.

What kind of primary voltage do you have in Tennesee? I have come across a number of FX transformers in the field installed by others. Again I found them to be no where near as powerful as what I have. They don't even have a 15 volt tap.

High Performance Lighting
03-18-2007, 12:56 AM
We have been using the Kichler Pro and Contractor series along with FX units on dimmed circuits and we have not had a problem with voltage drop increasing as we reach capacity in a couple of years. I wont try to make a broad statement about MDL made units, but I thought 900W+ units had already gone to Tordials and the rest would soon follow?? I tried to keep up on this but I gave up. I have not lab tested the two so I don't know, but Cast did and the results can be seen on their website.

We did get smoked on primary voltage increases on two large jobs last year. Both jobs were installed on properties with overloaded and failing cans that were replaced after our install. We had to rewire all the transformers and change a lot of lamps way too early.


Do me a favor-On your next project with these transformers please document the following

Incoming voltage unloaded
voltage outputs over each tap unloaded
Voltage outputs over each tap with a load (please state the wattage or amp load, approximate cable length and gauge
distance to each homerun, etc.)
Incoming voltage with transformer loaded

Much thanks

NightScenes
03-18-2007, 08:57 AM
I have been using the Kichler Pro and Contractor series transformers with great success. I will get the documentation on our voltage readings. Our primary readings around here are about 125 volts.

seolatlanta
03-18-2007, 10:38 AM
Well I am probably take a beating here but i am a big fan of the Unique line of transformers. I love the lug features and the voltage is always spot on. A lot of voltage at the receptacle here is @ 123 volts bot when I plug the transformer in and test the voltage inside the trans. it is always 120 volts.

I use the hub method of wiring and I have found this transformer to be the best for me.

I have tried Hadco and they have not been good as well as some Vista which I have to say I liked OK. I buy transformers as I need them and I cant get any Kichler products here. I can order them but it doesnt seem worth it.

High Performance Lighting
03-18-2007, 10:40 AM
I have been using the Kichler Pro and Contractor series transformers with great success. I will get the documentation on our voltage readings. Our primary readings around here are about 125 volts.

Thanks,
wow! 125 volts. I have never once registered a 125 volt reading in 17 yrs of doing this in Southern California. The highest I have ever seen unloaded is 122V and that is very very rare. the lowest 108V. Normally in the 117V-119V range unloaded. Once the A/C units and Pool filter go on it's even lower. Turn on an electric dryer together with these other two power hogs and I'm sitting on the curb with my head in my hands sobbing like a baby.

seolatlanta
03-18-2007, 10:43 AM
Also what are the differences between the torrodial transformers and others. Could you give me examples of each so I will know?

I just dont know that much about the two, I just know what I like and works for me.

I really appreciate all of the info i have gotten from this forum lately. I have really learned a lot.

Pro-Scapes
03-18-2007, 11:38 AM
dave i think thats been discussed try searching.

We usually have about the same as paul here 123-125v unloaded 120ish loaded.

I have readings I document this for every system I install. Headed to church now so will post em up later. We use Cast MDL units with no problems so far. The price is coming up a bit so may look into others soon.

Pro-Scapes
03-20-2007, 03:31 PM
went to a job this morning again... 128v!!!!! grrrrr

It seems to be this certain area of town thats over 100 yrs old.

This is a dedicated breaker right off the panel. about 2 ft of 14ga romex feeding it.

NightScenes
03-20-2007, 05:26 PM
Billy, be sure to check the manufacture of the breaker. If it's a square D, QO type breaker and you place your transformer within 10', you will trip the breaker from time to time. It wont happen all of the time and after awhile, you'll be pulling your hair out.

Might save you some gray hair,

YardPro
03-20-2007, 08:08 PM
Thanks,
wow! 125 volts. I have never once registered a 125 volt reading in 17 yrs of doing this in Southern California. The highest I have ever seen unloaded is 122V and that is very very rare. the lowest 108V. Normally in the 117V-119V range unloaded. Once the A/C units and Pool filter go on it's even lower. Turn on an electric dryer together with these other two power hogs and I'm sitting on the curb with my head in my hands sobbing like a baby.

we have consistent 124 volts here as well

Pro-Scapes
03-20-2007, 11:01 PM
Billy, be sure to check the manufacture of the breaker. If it's a square D, QO type breaker and you place your transformer within 10', you will trip the breaker from time to time. It wont happen all of the time and after awhile, you'll be pulling your hair out.

Might save you some gray hair,

different job......121.6v at outlet no load

wow you might be on to something. Just had the gfci and breaker replaced at a job where the gfci popped then if the trans cut on and off then on within about 10 seconds the breaker in the panel would blow. About 3 ft of romex on this one. Its the main panel at the meter with 2 sub panels inside the home.

All seems to be working well but they had an x 10 issue after the electricians did some work in the laundry room which is where I had the x 10 head. They moved the x10 to the garage and it was connected to a power strip and wouldnt send signal. Now its got a digital mini timer inside the trans, they didnt ever use the x10 anyways.

What can I do to ensure the 20a breaker doesnt pop? it is a square one like you speak of. To my knowledge is has not tripped yet since being replaced but its 45 min from home so I wanna be sure it wont. I think there is 7a of load on the 20a breaker. I do rememeber I checked amperage in the panel and at the trans and they were the same. Was starting to think the trans was bad because when I went to go look at it the first time if I clicked it on and off via x 10 remote a few times the breaker would trip.

NightScenes
03-20-2007, 11:15 PM
Billy, if it's a square D homeline breaker, you won't have a problem. The only one you have to worry about is the QO type of square D breaker. You can easily tell them apart by looking for a small window on the newer QO Breakers. The window has a trip indicator. The older ones don't have this window but have have smaller shape of the QO. I believe that the QO breaker is sensitive to the feedback from a transformer and trip. You can plug the transformer into an extension cord and then it won't trip. Of course this is only for testing as you don't want to plug a transformer into extension cords for normal operation.

One thing you can do to correct the problem is to make sure that there is at least 10' of wire between the breaker and the outlet that you are plugging into.

Pro-Scapes
03-21-2007, 08:47 AM
you mean the little window that turns red when tripped ? this does not have that.

If it happens again I will replace the trans... I think the start up current is a bit high. Not sure but also the photo cell cuts on a bit earlier than others I have seen... not really a problem but just baffles me a bit.

steveparrott
03-21-2007, 10:17 AM
A few points on these topics.

1. All the breaker mfgs. produce "High Magnetic (HM)" breakers that eliminate any inrush problems.

2. For a great explanation of transformer technology (including comparisons of EI and toroidal types), go to: http://en.wikipedia.org/wiki/Transformer also http://www.cast-lighting.com/art-transformer1.html.

3. An engineering study comparing a 1200W EI-type and a 1200W toroidal-type can be found at http://www.cast-lighting.com/art-trans-test.html. This study shows that loading a voltage tap on a good toroidal transformer results in about half the voltage drop compared to loading an EI-type.

Eden Lights
03-21-2007, 11:37 PM
I second the HM breakers, MDL made some changes to the transformers also. I havn't had this little monster in quite some time.

NightScenes
03-22-2007, 07:18 AM
I didn't know that the monster had been tamed. You only run into this situation on very rare occasions.

Pro-Scapes
03-22-2007, 07:46 AM
I drove past last night and the lights are working fine save 1 burn out I replaced. I wont mess with it til its an issue. I think the only thing that trips th breaker is if you have the inrush current more than once or twice within about 10 seconds (ie. playing with x 10 key fob as so many people like to do). I will for sure specify HM breakers in the future thanks for the tip