Wiring question for LED flat panels

[cybrdyke]

Edit: I did a quick Google search and it appears that standard is for the current draw of the ballast or LED driver. 2mA is the maximum current draw per fixture. So if the control is rated for 50 mA, it can control up to 25 fixtures.

To clarify, there are two ratings for these kinds of switches, the load and the dimming circuit.
The load rating for this particular Lutron switch is 8A, as mentioned above.
The dimming circuit is a little more complicated.

That's why I made this comment earlier:

If you are using lots of controllers, sensors, etc. then there are other considerations that will lower the number.

The 0-10VDC is created inside the drivers, so the controllers need to be rated for however much current all the drivers are putting out. 2mA is the MAX that IEC allows per driver, however common drivers dont get even close to that level. 200 microAmps per driver is routine, which would allow you to put a few hundred fixtures on a dimming circuit.
You will max out on the load rating before you'll max out on the dimming rating.
CD

 

[cybrdyke]

I don't think it's a non-issue or fixture manufacturers like EATON (Cooper, Metalux) wouldn't recommend Class 2 wiring (link).

The Class 2 recommendation is a UL thing, not a performance thing. It has to do with how well the power circuit is insulated from the control circuit.
CD

 

[Platonic Solid]

The Class 2 recommendation is a UL thing, not a performance thing. It has to do with how well the power circuit is insulated from the control circuit.
CD

According to the EATON document statement: "To reduce the risk of interference it’s highly recommended that 0-10V and communication wires be run as Class 2." it is a performance issue.

 

[Wrigley]

So, I am trying to source the wire that has been mentioned in this thread. 18 bell wire is easily found in my area but appears to only come in 50 foot lengths. Cyberdyke has suggested 16 or 18 gauge solid TFN. Can TFN and TFFN be used interchangeably in this application for the control wires? I can find TFFN but not specific TFN. Can plain old THHN be used? Oh and here is a good one, I have alot of this 14 gauge Xtreme dog 14 solid wire left over, any chance it could be used up? It has a different coating and cannot find the UL rating so I am going to venture to say that this is a non starter. the coating is .060 LD Polyethylene Triple Coating. I have called customer support and they cannot run down the UL listing number.

 

[garagelogician]

Does anyone make an all-in-one cable that can carry the line voltage to the lights, and shielded 0-10v conductors for the dimmer control? I would love it if I could just run one bundle in some 1/2" EMT and be done with it.

 

[cybrdyke]

Does anyone make an all-in-one cable that can carry the line voltage to the lights, and shielded 0-10v conductors for the dimmer control? I would love it if I could just run one bundle in some 1/2" EMT and be done with it.

It comes in MC cable:
https://www.encorewire.com/wp-content/uploads/EncoreWire-MC-LED.pdf
The control conductors are not shielded. This stuff is sold by the train-car load to the electrical contractors.

I have not seen it cabled any other way.
CD

 

[garagelogician]

It comes in MC cable:
https://www.encorewire.com/wp-content/uploads/EncoreWire-MC-LED.pdf
The control conductors are not shielded. This stuff is sold by the train-car load to the electrical contractors.

I have not seen it cabled any other way.
CD

I'm no sparky, but I thought the lack of shielding means it wouldn't meet code? Keep in mind, I have a small attached garage (27x19) and I'm only going to be installing 12 fixtures or less.

 

[cybrdyke]

I'm no sparky, but I thought the lack of shielding means it wouldn't meet code? Keep in mind, I have a small attached garage (27x19) and I'm only going to be installing 12 fixtures or less.

No. Once upon a time it was taboo to combine conductors of differing voltages in a conduit, raceway, or cable. The thinking was that if there was a failure in the higher voltage wire, it could put alot of voltage onto the low voltage conductor. Not a bad rule, if you ask me.
But now low voltage conductors can be included in the raceway with line voltage conductors as long as the insulation rating is the same for both. In the case of the MC cable mentioned above, both the electrical and the control wires are rated 600v. Shielding doesnt have anything to do with it.
CD

 

[howpeculiar]

You should easily be able to get a 500' roll of bell wire at your local box store. They use it for alarm systems all the time. There are a bunch of dirfferent 18/2 cables out there in 500' rolls. Use the term thermostat wire, alarm wire, or security wire.

 

[jjscott]

Ok, so I have the remaining lights on order and should be here before the weekend. Now I’m trying to select the appropriate dimmer switch.

I’m looking for one switch to handle the line load and dimming. There are two switches for the existing garage lighting. One is in the house and the other is in the garage. I would like to replace the one in the garage with the new combo dimmer/light switch and leave the one in the house alone.

The new lights are rated at 72 watts and will run on a 120V circuit. There will be 9 of them installed, and if my math is correct, that should be a max load of 5.4 amps.

I reviewed several different dimmer switches, including many in this thread and really like this one mainly for aesthetics and future proofing. https://www.homedepot.com/p/Lithonia-Lighting-LED-Troffer-Dimmer-Switch-ISD-BC-120-277-WH-M10/202986061

It’s from Lithonia Lighting and looks like it is rated for 1200 watts, so that should easily cover my current project. The link states it’s for a Lithonia Lighting 2x2 LED Troffer. If you scroll down to the Q&A section of the attached link you will see someone asked if it will work for a 2x4 LED light and someone from Lithonia responded that it is for use with their 2x2 troffer. Not sure if this means it is only designed for the 2x2 or if they are just covering themselves and it can with any other LED light provided you don’t exceed the stated 1200 watt limit.

Can you guys take a look and let me know if you see any issues with it?

 

[cybrdyke]

If you scroll down to the Q&A section of the attached link you will see someone asked if it will work for a 2x4 LED light and someone from Lithonia responded that it is for use with their 2x2 troffer. Not sure if this means it is only designed for the 2x2 or if they are just covering themselves and it can with any other LED light provided you don’t exceed the stated 1200 watt limit.

Can you guys take a look and let me know if you see any issues with it?

That's a big red flag to me. Although it seems a little odd, it's not unusual in LED-world. The dimmer has to be compatible with the driver. For some reason, the response from Lithonia indicates that this dimmer works with their 2x2, but not with their 2x4. IF that's true, then there is some difference in the drivers.
If it was just some random person saying that, I'd disregard it, but since it was a response from Lithonia, I'd heed it.
CD

 

[Platonic Solid]

Maybe someone at Lithonia was having a bad day and decided to be intentionally vague. Darn expensive dimmer. At that price I'd expect it to be a Lutron with trailing edge dimming. Is it really worth the extra $57 over the dimmer switch from the panel manufacturer LumeGen?

Edit: You would be maxing out the 720W LumeGen with your 648W load.

 

[jeffhay]

I'm doing basically the same build (no build thread yet) and used everything in this thread to get there. Your questions were very specific and thorough. Mine is 24'x32'x10' with 9 of the 72w panels from LightUp. I used one of their 6a dimmers. These lights, dimmers and flush mount kits were all backordered but mine shipped yesterday so they must be back. I ordered 2 to test and will order the remaining 8 next week. Please leave me some

My contractor offset the fixture centers from the walls by 5'9" before I could tell him to push them closer. He just did the math from the center of the ceiling and went symmetrical. He left longish whips of romex, so I hope I can fudge them a little closer. Dialux says I may end up with a mere 65fc at 34" work surface at the walls, if not.

Thanks jjscott and Platonic Solid for all the help you've given this lurker.

 

[jjscott]

Maybe someone at Lithonia was having a bad day and decided to be intentionally vague. Darn expensive dimmer. At that price I'd expect it to be a Lutron with trailing edge dimming. Is it really worth the extra $57 over the dimmer switch from the panel manufacturer LumeGen?

Edit: You would be maxing out the 720W LumeGen with your 648W load.

Yeah, I thought they may have been intentionally vague in the response since they have no way of knowing what type of light someone may be using with it.

I thought as long as it was a 0-10v LED dimmer there wouldn’t be a problem. Really makes me wonder about the hundreds of other 0-10v switches out there from a compatibility perspective.

Not sold on the LumGen dimmer as I would be pretty close to maxing it out and I don’t want multiple dimmer circuits. Gonna try to call Lithonia tomorrow and see what they say.

 

[Platonic Solid]

Running 648W on a 720W rated switch isn't a problem if there's only 1 dimmer switch. Switches are derated as you put more than 1 next to each other. The wattage rating for the switch applies only to the ON/OFF function as dimming is performed by the separate 0-10V circuit.

 

[jjscott]

I checked with Lithonia, more specifically, Synergy, and they said the dimmer switch can be used with any LED light requiring a 0-10V dimmer switch. So, no problems on this one.

Still checking a few others at this point.

 

[jjscott]

According to the mfg’s installation guide, they call for #18 AWG wire for the low voltage dimmer circuit for runs up to 500 ft. Mine will run about 90 ft so #18 will work for me. The one thing they don’t specify is whether it should be solid or stranded wire…maybe it doesn’t matter? Anyhow, based on “potential” signal interference, I was going to run shielded wire, but I can’t seem to find it in #18 solid wire for a 100 ft spool without paying a significant price. I can find #18 stranded all over the place for a decent price.

So my question is…does it really matter if I use solid or stranded wire? It’s my understanding that #18 AWG stranded is slightly larger than #18 AWG solid due to the gaps between the strands.

Let me know what you think.

 

[ShakeyPuddin55]

I ran 16 gauge stranded. No issues.

 

[jjscott]

Thanks. How many feet was your run?

 

[ShakeyPuddin55]

Thanks. How many feet was your run?

Max run was around 120ft

 

[Makoto]

I have a 300 lumen flashlight on my rifle that'll blind you. i can't imagine 10K lol

 

[Radix2]

I used the shielded 18-2 from Lowe's - https://www.lowes.com/pd/Southwire-500-ft-18-2-Stranded-Shielded-Grey-Security-Cable/50111502

The 18-2 thermostat wire is the unstranded option.