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Hi guys,

Attached is the layout of my house and LOR setup. I have a question on the electrical from the power box to the LOR's. I am using the the 16 channel Deluxe LOR's.

I have an existing power line which is 12/3 from the power box to a breaker for my sprinkler pump at the front of the garage. This will not be used at the time of the display. I will be adding a junction box there.

You can see the distance from the power box to the junction box. Then from the front of the garage to another junction box on the front porch and then to the 5 individual LOR units. You can also see the distance for each of them in my image.

Would like to know if you think that going with 12/3 is too much or not enough?

Thanks in advance!


Attached files 52195=3054-lor-1.gif

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I'm by no means an electrician but I have a little knowledge of it.

Well I guess it depends on how many lights you'll have per LOR box.

If I was doing the exact same thing, I would run seperate 10/3 w/ground to each controller. The max amps per LOR controller is 40 amps (20 amps each side) which is what I would go off of.

You have 5 LOR controllers. I would run 5 different circuits 10/3 wire to each LOR controller and hook to 30 amp breakers (2 30 amp breakers for each LOR box).

This is only my thoughts so it might not hurt to get a second opinion.

Edit: when I mentioned running 10/3 to each controller, I should say an double outlet box to each controller that the controllers can be plugged. Using MC cable, it's flexible and can be rolled up after each season and hung by the C/B panel. Or build 5 dual outlet boxes next to the C/B panel and run extension cords to the controllers.



Tom

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I might recommend that you purchase an "electric clamp". This simple handheld device simply measurers line amperage. They range in price from $15 - $75+. I have been very happy with a $60 digital model. Digital models eliminate looking at the wrong voltage line on an needle indicator type. It is cheap insurance to assure not melting the wires.

The electric clamp can additionally be effective to “Balance” electrical loads. This helps to assure that no one circuit is near it’s maximum, thereby helping to eliminate a nuisance during display hours in terms of a tripped breaker, warm wires or possibly much worse.

In addition to the limits of the breaker and 12/3 cord capacity, be certain to not exceed the specific LOR limits, both the individual channel limits as well as the maximum amps per controller box. Specifics are well documented in http://www.lightorama.com.

By using an electrical clamp, you will be dealing with real facts for your specific situation, and can compare that with the manufactures stated load limitations.

Personally I NEVER (ever) run more than 80% of a cord or circuits capacity. Occasionally it has been a real pain, however, I have also never tripped a circuit breaker in the last six years running 25,000+/- light bulbs.

Good background information can be found at:

http://www.planetchristmas.com/FigurePower.htm

Greg Zimmerman

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Hmmm, well I wonder if I ran a thicker line from the main panel to another breaker box at the front of the garage. Will have 5 outlets there for each of the LOR's. Would using extension cords from there to the LOR's be enough? Max run is about 75 feet.

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Edited: Added attachment for you to see.

The circuit breakers are double pole breakers (thats 2 breakers per outlet box)

The attachment shows 3 wires going to each box. 2 hot wires and 1 neutral (don't forget about the ground wire).

30 amp breakers 10/3 with ground to each outlet will give enough assurance of not over heating the wire.




Attached files 52206=3055-untitled.JPG

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Brad Stevens wrote:

Well make sure your neutral can support the power being drawn on both hots at the same time. Lets say you pull 30 amps on both hots, your neutral should be able to support 60 amps. To make this easier, and use the same wire on the entire project, I would use a seperate neutral for each hot.
A neutral wire is only to carry the unbalanced load of a 240 volt circuit. The neutral will not have to carry 60 amps if the hot side is only 30 amps. That means... if the load is 30 amps on each side, it will balance out in the end.
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mountainwxman wrote:

A neutral wire is only to carry the unbalanced load of a 240 volt circuit. The neutral will not have to carry 60 amps if the hot side is only 30 amps. That means... if the load is 30 amps on each side, it will balance out in the end.

So that explains why there is 10/3 with ground and not 10/4?

Tom
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When wiring with a common neutral as shown in Santas Helper's diagram repeated below there are a few important considerations, see comments below diagram.

attachment.php?id=3055

Make sure you use two adjacent breakers (preferably a double pole breaker.) The two reasons for this are 1) when you turn off the double pole breaker all power to the outlet box is removed. You won't make a potentially dangerous mistake when you think the power is off. 2) When you are using only one side of this pair of circuits, the neutral carries all the return current. When you use both sides, because the two sides are 180 degrees out of phase, the neutral is offloaded because current flows between the two hots. This effect permits you to have a neutral of the same gauge as the hots.

The second consideration is very important. If your neutral should become disconnected, then it depends upon the loads on the two circuits how the voltage gets divided. You could potentially end up with close to 240 volts across one circuit and that would fry everything.

Those things said, this is a very common method of distributing power and I use in several places.

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I'm planning to do something similar, but will have to use the 'tandem' or 'twin' mini breakers due to capacity in my panel (modern 200 amp panel, just lots of moderately utilized circuits). I of course will use one line from each adjacent pair to ensure I'm running off two seperate phases for the 12/3 runs, but that leaves 4 breakers in two adjacent spots that need to be coupled as 'doubles' or 'quads' for safety on the 'thumb' side of the breaker.

I've seen the add-on clamps for making two adjacent standards coupled in the past. Do these still exist (and are they acceptable to most local electrical inspectors), and do they exist for tandem/thin breakers? What are they called so that I can find them online or ask for the right thing at my local electrical supplier?

Thanks,

Moving Target

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A note that may be worthy of mentioning here. I have seen this mentioned in many discussions on power distribution. However, it seems the terminology get confused so I thought I would try to present some clarification.

A tandem breaker is a breaker using ONE side of the panel but provides 2 seperately protected circuits. A double breaker is one that physically connect to both sides (busses) in the panel. It is the double breaker that MUST be used in the above diagrams as John pointed out to keep from overloading the neutral.

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Wow, thanks for the diagram guys. Hope you don't mind me asking a couple of more questions.

From the Main panel to the sub panel. What size wire would be appropriate here?

Are you saying that each side of the CTB16D's circuits sould be on it's own separate side of the dual outlets or does that really make a difference? Check my diagram out to see what I am saying.

Also, are you saying that I should run the dual outlets to where the LOR units are in the yard, or leave the outlets against the house and run extension cords to the LOR units?

Thanks again for the great help.





Attached files 52297=3065-LOR 1.JPG

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llbarnes wrote:

From the Main panel to the sub panel. What size wire would be appropriate here?
You might check it out but I think the 6 gauge wire. It's the big stuff. Remember the possible amps your going to use.
Are you saying that each side of the CTB16D's circuits sould be on it's own separate side of the dual outlets or does that really make a difference? Check my diagram out to see what I am saying.
Yes
Also, are you saying that I should run the dual outlets to where the LOR units are in the yard, or leave the outlets against the house and run extension cords to the LOR units?
Extension cords would do the same thing and be cheaper and easier for you probably.
Tom
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llbarnes wrote:

#6 wire? Wow. That seems pretty thick. I don't want to take any chances by any means but is this necessary? Isn't that whats used for A/C units?

Thanks

Well if your going to run a sub panel from your main C/B box and that sub panel is going to power 5 LOR controllers with 16 channels on each, you might need every bit of that. Add up how many amps total (keep in mind the 80% factor) then ask an electrician or Lowes/Home Depot what size wire would they suggest for that many amps.

Let me know what you find out. My example of #6 wire was a guess, you might need bigger or you might need smaller but your sub panel is going to power a bunch of lights.

Tom
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Hi Tom,

I ran down to Home Depot during lunch to check out what I thought was #6 and I was wrong. You are right. I can see using the #6 for sure. I thought #6 was even larger. Regardless of any information I get online from anyone, I plan on having an electrician check it out first.

Thank you again for everyone's help.

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