Electrical

[ShawnT]

OK - I am now ready to have a certified electrician come out and put in my electrical outlets.

But I am not sure how many I need. I have 8 of the PC controllers. Will I need 2 15 amp outlets per box for a total of 16 outlets?

[Ponddude]

It really depends on the amps that each channel is pulling. I only use PC controllers and I have each one plugged into a 20 amp circuit. Remember, the breaker will trip when it hits 80% of its limit. So a 20 amp circuit will blow when it hits 16 amps. You can't get that much power out of any side of the PC controller, so I am good. I don't really ever had ALL the lights on at once, so my power demand isn't that high. It also depends on if your using LEDs or regular incandescent lights.

[JeffF]

It really depends how you are going to use those boxes. I have three CTB16PC controllers that I'm using for leaping arches and I'm going to run all three of them off of one 15A circuit. 9 channels per arch x 4 arches x .3A per channel = 10.8A And that 10.8A is if every channel is on which will almost never happen, and it will never happen for more than 1 or 2 seconds.

And if you are using LED lights, you can probably run your show off of a couple 20A circuits.

You really have to decide how much of a current draw you are going to have on each controller(and each channel on each controller).

I just finished my summer electrical project here...
http://www.mainelights.org/OutsideOutlets/

I basically designed the show and then decided where I needed the power. (I'd like to say I was smart enough to come up with that idea on my own, but I got it from reading all the different Christmas light forums)

Good luck,
Jeff

[DownTown]

Shawn -

If you intend to run your controllers near capacity, you will need 2 circuits per controller. If you will be running less than 15 amps per controller, you can get by with a single circuit to each controller. If you intend to have more than 15 amps of light per controller, or there is a chance you will increase your display in the future, you will do well to install the additional circuits now...



D.T.

[DownTown]

Ponddude wrote:

Remember, the breaker will trip when it hits 80% of its limit.

NOT! The breaker will trip when it surpasses 100% of the rated load. It is recommended that when you install the circuit, you do not exceed 80% of the circuit's rated load, but it will carry the full load.

D.T.

[Ponddude]

DownTown wrote:

Ponddude wrote:

Remember, the breaker will trip when it hits 80% of its limit.

NOT! The breaker will trip when it surpasses 100% of the rated load. It is recommended that when you install the circuit, you do not exceed 80% of the circuit's rated load, but it will carry the full load.

D.T.

I was close...LOL

[ShawnT]

OK - so it sounds like I have some work to do by entering in my lights per channel and controller into the spreadsheet that I found to find out what my load is going to be per controller.

30 amp max - 15 amp per side.

In most of the layout and design I have at most 3 strings of mini's per channel. That should be around 9.25 amps per side. That is under the 12 amp (80% of 15 amp) usage.

To be safe I will enter in all my information that I have into the spreadsheet and see if I am over in any areas.

[John Hertig]

No matter how you wire it, you are going to need 16 outlets to plug the 16 cords from those 8 controllers into. The variations will be how you wire those outlets.

If you plug each power cord from the controller into a separate circuit (i.e. fed from different breakers at the fuse panel), with nothing else on that circuit, you can have 15 amps per 8 channel 'side', for a total of 30 amps per controller. You will need 16 outlets (can have each outlet in each double outlet powered separately, or you can have 2 outlets fed by each circuit for future use) and 16 15 amp circuits (wiring and breaker).

If you plug both power cords from the controller into the same circuit with nothing else on it, you can have 15 amps per 8 channel 'side', for a total of 15 amps per box or 20 amps per box if the circuit you plug into is a 20 amp circuit. You will need 8 pairs of outlets and 8 15 or 20 amp circuits (wiring and breaker)

If you plug multiple controllers into the same circuit, it cuts down the available current per side and controller, but even if they are all on the same circuit (not recommended), you still need 16 outlets to plug the 8 controllers into.

It is wise to have nothing else except decorations on any of these circuits. My first year (static display), I set up using the circuit with the freezer on it. Everything was fine until the freezer kicked. No lights and no freezer... If you must use a non-dedicated circuit, make sure whatever is on it is not automatic and is unplugged or with a big sign across the power switch so it is not turned on while the lights are going.

Don't forget that you can have 15 amps per 8 channels, but at most 8 amps (if you have the heavy duty heat sinks) per channel.

To decide what wiring option to go for, figure out what the maximum current per controller side you will use, and at least double it for future expansion. I'd run extra wires too for future circuits; shouldn't be much more cost without the additional breakers and outlets, but would make future additions much easier. When I put in my 20 amp lighting circuit, I ran a spare wire for a future garage conversion. When I used up my 20 amps for lighting, I just attached the outlet and breaker to that spare wire and got another 20 amps 'instantly'.

I'd put in 20 amp circuits wherever I could. You can power 15 amp things from a 20 amp circuit, but you can't power 20 amp things from a 15 amp circuit. Even if you don't think you will need that much power, keep in mind possible future needs.

[Papa-LF]

DownTown wrote:

Ponddude wrote:

Remember, the breaker will trip when it hits 80% of its limit.

NOT! The breaker will trip when it surpasses 100% of the rated load. It is recommended that when you install the circuit, you do not exceed 80% of the circuit's rated load, but it will carry the full load.

D.T.

And even then .. Plan, Calculate, and Measure your loads.

Last year while trying to determine the cause of a GFCI tripping - I had moved things around from the 4 - 20 amp outlets I have available. Not noticing that I had overloaded one of the circuits, I ran the show. While inspecting things one day during the show I noticed a overly warm extension cord. Placing my clamp on amp meter on the cord - it was pulling 21.6 amps. I added a 100 watt bulb to the circuit and it did then trip, but it was holding at the excessive load.

Was a good reminder to me to follow my plan. So Plan, Calculate, and Measure the loads.

Note - I did find the cause of the GFCI tripping - corrected the issue and ran the entire season with no more trips, Safety First!