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pete scalia
12-19-2007, 11:49 PM
Does a 12 gauge power cord result in less voltage drop than an 18 gauge power cord on a transformer?

Eden Lights
12-20-2007, 12:36 AM
We would need more information to answer your question, but you can use the voltage drop formulas you already know to answer your question.

pete scalia
12-20-2007, 12:39 AM
We would need more information to answer your question, but you can use the voltage drop formulas you already know to answer your question.

please explain? I'm talking about the power cord plug. Not LV cable.

Eden Lights
12-20-2007, 12:59 AM
Voltage drop formulas are the same, just plug in the numbers and you will have your answer or post all the information and we can help you out. ( length, amps, volts, and etc.)

pete scalia
12-20-2007, 09:08 AM
Voltage drop formulas are the same, just plug in the numbers and you will have your answer or post all the information and we can help you out. ( length, amps, volts, and etc.)

What in God's name are you talking about? Am I in the Twilight Zone?

Eden Lights
12-20-2007, 09:32 AM
Is this a joke or what? If you have a 6ft power cord with a 5 amp load at 126 volts you run the numbers for various wire sizes just like you do on the LV side. The formulas are the same.

pete scalia
12-20-2007, 08:49 PM
Is this a joke or what? If you have a 6ft power cord with a 5 amp load at 126 volts you run the numbers for various wire sizes just like you do on the LV side. The formulas are the same.

I will re format the question


If I place a load on the transformer and have an 18 gauge power cord attached and take voltage readings at my homeruns and record them

If I then replace the 18 gauge 6 ft cord with a 12 gauge one will the voltages be higher at the homeruns. All other things the same.

This is all I ask or should I just test this for myself to find out. Does anyone else care? There are transformers with 12 gauge and Transformers with 18 gauge cords. Why is this?

Is there voltage drop from the power cord gauge or does it matter since it's negligible?

Grazie.

Eden Lights
12-20-2007, 09:51 PM
Ok, now tell us the primary amp load and I can run the numbers on a six foot cord.

pete scalia
12-20-2007, 09:53 PM
Ok, now tell us the primary amp load and I can run the numbers on a six foot cord.

well let's just say it's a 1200VA transformer and for the heck of it has a 9 amp primary load.

Chris J
12-20-2007, 10:34 PM
The transformer is going to reduce the primary input by a power of 10. If you have 120v coming in, your 12v lug should read 12v. If you reduce the size of the primary cord, the end result is going to be so minimal that it is not going to matter. For instance, let's just say that by reducing the cord size your incoming voltage dropped to 119v. Your out put at the 12v lug would then be 11.9v (who cares).

irrig8r
12-20-2007, 11:27 PM
Nightscaping Powercenters starting arriving with new fatter and shorter cords maybe a year ago. I heard it was to comply with UL. I don't have a spare one out in the garage right now, so I'll have to get back to you on the cord thickness, but it seems to me it's

Three foot (rather than 6 ft.) cords were a pain to begin with, and the thickness made for some problems with WP covers, but I've since found the newer Taymac MM740C-B and MM740GY-B covers with the glued on gasket is suited to the newer cords.

Who makes a TF with an 18 ga. cord?

pete scalia
12-20-2007, 11:33 PM
Nightscaping Powercenters starting arriving with new fatter and shorter cords maybe a year ago. I heard it was to comply with UL. I don't have a spare one out in the garage right now, so I'll have to get back to you on the cord thickness, but it seems to me it's

Three foot (rather than 6 ft.) cords were a pain to begin with, and the thickness made for some problems with WP covers, but I've since found the newer Taymac MM740C-B and MM740GY-B covers with the glued on gasket is suited to the newer cords.

Who makes a TF with an 18 ga. cord?

Nightscaping, used to, I believe unique and Vista still do and in the case of vista they are 1838 and suitable for use with underwater luminaires.

klkanders
12-21-2007, 09:42 AM
The Kichler Pro Series transformers I use have the 3' #12-3 cord. However they also make some Economy transformers with 6' #16-3, #18-3 cords.

Gregg, I agree the thick cords are a pain with the covers. I have been enlarging the cord openings with my battery operated sawzall.

INTEGRA Bespoke Lighting
12-21-2007, 10:10 AM
The Kichler Pro Series transformers I use have the 3' #12-3 cord. However they also make some Economy transformers with 6' #16-3, #18-3 cords.

Gregg, I agree the thick cords are a pain with the covers. I have been enlarging the cord openings with my battery operated sawzall.

Nightscaping made the change a year or so ago to 3' #12 power cords in order to comply with a change in the UL listings. It does present some issues and you have to ensure that you located very close to the receptical.

As for enlarging the cord openings on the weather proof while in use covers, I have found this very easy to do using my diagonal wire cutters. Only take a second and "snap" it is done.

Have a great day.

JoeyD
12-21-2007, 10:32 AM
If you have 120v at your wall and you only have 11v at your 12v tap with or without a load you have a crappy TF. Ours drop less than any other unit on the market. We used to have in our training room a wall of all the TF's available to show how the TF has drop before even putting a load on them. So as for switching power cords, why do that, switch manufacturers. With a full load my unit MIGHT drop a half a volt where others could driop a full volt or more.

Chris explained how the units work on a 10/1 ratio. This is correct. 120v equals 12v toyour 12v tap, most manufacturers will still show a drop there though.

I would not mess with the power cord but if you are trying to band aid something then maybe it will help slightly but more than likely Pete it isnt going to change much.

irrig8r
12-21-2007, 10:56 AM
Nightscaping made the change a year or so ago to 3' #12 power cords in order to comply with a change in the UL listings. It does present some issues and you have to ensure that you located very close to the receptical.

As for enlarging the cord openings on the weather proof while in use covers, I have found this very easy to do using my diagonal wire cutters. Only take a second and "snap" it is done.

Have a great day.

If you use the larger compartment Jumbo model Taymac cover I mentioned above, there should be no problem w/ the fatter cord. It has a single cord slot, centered, and a deeper 4 3/4" cover to accomodate the bend.

http://www.taymac.com/taymac/mm2.html

JoeyD
12-21-2007, 11:02 AM
BY code our cords have to be 6ft and the Pool and Spa have to have 10ft cords.

irrig8r
12-21-2007, 11:14 AM
Joey, define "our".
You mean Unique's cords? Or do you mean all LV lighting TFs?

And when you say required you mean exactly those lengths?
No longer than? No shorter than?

JoeyD
12-21-2007, 11:20 AM
I only speak for us. I dont know what everyone else does. Seems they all apply different codes and techniques to their units. I still only know of Unique and NS making their own units. Does this hold true? Does anyone know of other manufacturers makign their own? I think CAST does. I dont consider putting someone elses coil in a can making their own by the way.

INTEGRA Bespoke Lighting
12-21-2007, 11:54 AM
I am pretty sure CAST transformers are made by Qtran. Perhaps Steve P. can confirm this.

klkanders
12-21-2007, 07:34 PM
I have used the deeper covers but still find the cord tough to bend. I wish they came with a 90 degree plug. Does anyone manufacture them this way?

pete scalia
12-21-2007, 08:02 PM
I am pretty sure CAST transformers are made by Qtran. Perhaps Steve P. can confirm this.

Looks like an MDL to me.

Chris J
12-23-2007, 11:25 AM
I'm pretty sure Cast and Kichler transformers are made by the same folks....MDL.

Pro-Scapes
12-25-2007, 01:08 PM
yes MDL makes em both to Kichler and Casts specs. Cast chooses to add the extra common which comes in handy and kichler chooses to tilt the terminals slightly which is really of little help sometimes.

Cast is slightly more refined I feel with the locations of the timer plugs allowing a wider range of control options. With Kichlers you need to invert the relay plug to accomadate some.

Cast now offers "soft start" which is supposed to help reduce failed lamps.

I have been installing Kichlers this summer. I went back to CASTS on my last project. Coppermoon also offers the MDL trans as do others such as garden light and I think its hadco.

I may use some i forces from joey if they can ever get em right and put a decent chase pipe in there and a provision for attaching a conduit.

JoeyD
12-26-2007, 01:07 PM
Billy,
The IForce has the correct provision for attaching conduit, it is on the inside. The pipe runs down the rear chase compartment. You relaly need to handle one, you will see that it has all you that you ever dreamed of!! Hope you guys all had a merry Christams!!

Joey D.

Pro-Scapes
12-26-2007, 06:51 PM
im still recovering from the fact I cant put my astro timer inside the multimatic. Yall riveted the casing shut so I cant invert the plug like I do on the Kichlers.:hammerhead:

Any tricks to popping the plug out ?

JoeyD
12-27-2007, 12:46 PM
You can try to pry it out. It is held in by 2 prongs but it can be tuff since we switched to metal prongs to hold the plugs in.

Pro-Scapes
12-27-2007, 04:43 PM
i tried to pop it but i think you guys jb welded the thing in there or something. It chipped the outlet. So short of drilling out your rivets and reinstalling new ones im at a loss. One day a manufacture will make a trans that is compatible with ALL popular controllers.

UPB
X10
Astro timers
sequencers

I think your at 50%... have not have a chance to see if I can slam a UPB in your trans yet Joey. Anyone do it yet ?

SamIV
12-27-2007, 05:54 PM
Joey,

I looked at your one of your transformers briefly a couple of weeks ago at Billy's, so this is all the experience I have. I will try not to seem demeaning here, but I am on Billy's side. Your trans seems well constructed and I like your terminal lugs but for me they are too small. Billy and I still like to use 10 ga. on wire runs. How many of you guys are 12 gaugers. And what's with all the rivets?

Also a 3/4 or 1/2 inch conduit knockout is a bit slim for us. Remember, we have only dealt with MDL and are very accustomed to these. All MDL's I have encountered could use a larger wiring compartment and maybe a terminal lug that could be to removed when I have more than 3 - 10 ga. wires to jam in. I really like the idea of the I-Force, but sounds like the chase is not very accommodating for my taste. I guess it is what you are accustomed to. Just not real familiar with your transformers.

SamIV
Accent Outdoor Lighting

JoeyD
12-27-2007, 08:39 PM
Hey Sam!
Billy, I agree it would be nice for us to accommodate all timer sizes and modules. Most we do accommodate. The IForce runs into some issues when trying to install a bottom plug module or timer. I am going to get with my PE (product engineer) and see what we can do to accommodate more timers and modules. I know our standard multi matic models will accept just about all timers and modules but the IForce is a bit more limited.

The reason for all the rivets is simple. You guys have not seen the inside of the unit and how we mount our coil to what we call the C Bracket. We utilize rivets to mount the coil we then have to use rivets to seal the can to the C Bracket and Lid. We want to make sure we never have a problem with the cans not holding together in shipping. Believe it or not the units take more abuse in shipping then they do once they are mounted and in operation.

Now as for the smaller holes on he lugs. I had it out the other day with my PE that the lugs were too small. I told him I did not think we could fit an 8ga wire into he lug, we then went out to the factory and sure enough we could fit 8ga without a problem. The jackets present more of a problem trying to squeeze them in when you have more than 3 going into a hole. It does take some getting used too but you will find it is tight but you can make it happen. In the mean time we will be meeting on this subject again to decide if we want to go to a single hole lug like our IForce.

Now as for the knockouts, our multi matics will now be able to accept up to 3/4" conduit. I will look to see if we have upgraded the conduit plate in the IForce to accommodate a larger pipe as well.

Thanks for all your input, this will help us in developing better products for you guys!!!

Joey D,

Pro-Scapes
12-27-2007, 11:10 PM
great Joey. Glad to provide feedback for someone willing to listen and make the changes.

While your at it we want about 12 inches of wiring compartment space but dont make the cabinets bigger :)

I know the perfect transformer layout is out there and will crush the market if it can be produced at a reasonable cost.

NightScenes
12-27-2007, 11:31 PM
Joey, I like the looks of a single larger conduit coming into a transformer. The units I use have a 1 1/4" KO for a nice clean look.

klkanders
12-28-2007, 10:07 AM
Same here Paul. I have always used the larger KO for the beefier look and ease of pulling wire. I mentioned earlier I just wish the transformer plug was a 90 degree version for ease and better look under the outlet cover.

Pro-Scapes
12-28-2007, 10:25 AM
same for me. We always use the 1 1/4 and have plenty of room. I think Cast has even gone to 1 1/2 on the newer big boys and include the conduit... nipple and lockring with it.

90 degree cords would be slick in most cases but what if you have something else plugged in there too ? we often plug in with the irrigation timer or have 2 600's plugged in together.

INTEGRA Bespoke Lighting
12-28-2007, 10:25 AM
The problem with using a 90 deg. plug at the end of the transformer supply wire is that these tend to block the second outlet of the receptacle. This is especially problematic when you are using 'weatherproof while in use covers' which tend to limit access to the receptacle.

Unless the receptacle is dedicated to supply the transformer with power, this can be a problem.

klkanders
12-28-2007, 10:38 AM
Ya guys I see what you are saying especially with the deeper in-use covers. OK then how about a 45 degree cord? :)

JoeyD
12-28-2007, 11:27 AM
I really do appreiate the feedback. I am cutting and pasting your feedback into an email to my PE as we speak. I would love to see a larger knockout as well. Oh and byt he way I amde a mistake yesterday. When reading my response I had a brain fart and meant to tell you guys our new units will accept up to 1" conduit. We have always been 1/2" and 3/4" now we will be 3/4" and 1" on all units.

Pro-Scapes
12-28-2007, 11:31 AM
your transformers seem rather compact compared to some Joey... Why cant we just make it a bit bigger to include all these. I think when a manu brings the perfect contractor inpired trans to the market (nates been a manu too long to qualify) he will make a ton of em. The Iforce is a very innovative idea.

On another note.. . the vented cans may not fly to well here. We have some nasty wasps and dirt dobbers that would love to nest in there.

JoeyD
12-28-2007, 11:33 AM
The occasional bug nest occurs on all units vented or not. I think it is ineveitable to have a bug cozy up to the warm unit.

pete scalia
12-30-2007, 02:34 PM
your transformers seem rather compact compared to some Joey... Why cant we just make it a bit bigger to include all these. I think when a manu brings the perfect contractor inpired trans to the market (nates been a manu too long to qualify) he will make a ton of em. The Iforce is a very innovative idea.

On another note.. . the vented cans may not fly to well here. We have some nasty wasps and dirt dobbers that would love to nest in there.

Transformers are in the ice ages. When will someone step up and do the right thing?