Question about wiring lights.

[hanly2]

I finally finished my ceiling and started installing my new ballasts in my lights. Now I am ready to move on to the installation. I have 8' 4 bulb t8 fixtures. I am going to run 3 rows of 3. And I would like to but them up against each other and run the wire inside. I would like to also put 6 on 1 switch and 3 on another. I plan on screwing 2x4s across the trusses and then screwing the light to them. I have a roll of mc 12/2 that I am going to use for the runs and then use some romex or something inside to connect them all. Also read about feedinf the fixture not the switch, but having a hard time picturing all this. Can someone verify this all will work and how to do it?

 

[Mustang51js]

Need a threaded ****** or chase ****** to **** them up together

 

[hanly2]

Ok. What does that do for me?

 

[Aceman]

You shouldn't need a chase ******.

All the strips I've wired when mounted end to end, you leave the end plates off the ends of the fixtures. Then take one end plate slide it into a slot inside the end of one fixture, screw it in place, then slide the end of the other fixture onto it. Then screw through the plate into the second fixture.

It basically makes the fixtures into one long fixture with a fullsize wiring chase between them.

As for wiring, take your hot to the switchbox first, then the lights. From that box take one "switch" wire to one set of lights that you want to switch. Take another switch wire from that box to the other set of lights that you want to switch separately.

Use individual THHN wire to chase through the lights to connect them together.

 

[hanly2]

So use same gauge as the ballast or same gauge as the feed? Also does the end plate attach to the side or top of the fixture? If I just **** them up with no end plates it also gives me wide open space.

 

[Aceman]

So use same gauge as the ballast or same gauge as the feed?

Feed.

Also does the end plate attach to the side or top of the fixture? If I just **** them up with no end plates it also gives me wide open space.

Look inside the fixture at the end. There should be a slot the width of an end plate at the back of the fixture.

 

[Charles (in GA)]

Your black and white feed wires need to be sized to the breaker you are using. 12 gauge = 20 amp and 14 gauge = 15 amp. Lighting is a continuous load as defined by the elect code, and you are not allowed by code to load a continuous load circuit to more than 80% of capacity, thus a 20 amp circuit is max at 16 amps and a 15 amp circuit is maxed at 12 amps. Use the amp rating on the fixture data plate or the ballast of the fixture to calculate this.

Ground wires need to be screwed to each fixture, and you need to scrape off paint and get a good contact to the steel at each ground screw. You will have problems if you don't. Don't know why, but poor grounds are a contributor to why flo lights won't light up sometimes. I've seen it and others on this board have also mentioned that they too have experienced this.

Indeed, code requires a neutral at the switch now, so take your hot/neutral/ground to the switch box first and then up to the fixtures. Do NOT strip wire out of Romex, use the proper THHN wire, as it is properly marked. Flo fixtures get HOT so be sure and use 90°C rated wire or better. All of the THHN I've ever seen has this rating and is stamped right on it.

Charles

 

[hanly2]

Ok 1 more ? Should I be connecting these all in the first light or just the feed in the first, then 3 wires to the next light connect them then again. That way I would have a max of 2 connections in each instead of 6 in 1.

 

[Charles (in GA)]

You take the white, black and ground to the first fixture, connect to the ballast AND wires going to the second fixture, same at the second fixture, connect to the ballast AND the three wires going to the third fixture, and so on. No need to homerun each fixture to a massive splice in the first one.

Charles

 

[hanly2]

Thanks.

 

[ManCave]

If you do a search on INSTEON here you'll find some discussions on how you can eliminate some of the wiring to the switches.

 

[bradweingartner]

If you do a search on INSTEON here you'll find some discussions on how you can eliminate some of the wiring to the switches.

Insteon (and the other similar technologies) are great, and I use them myself! But I wouldn't say it's meant to be use as a shortcut to wiring switches. Especially when your walls/ceiling are already bare framing.

 

[n8n]

Your black and white feed wires need to be sized to the breaker you are using. 12 gauge = 20 amp and 14 gauge = 15 amp. Lighting is a continuous load as defined by the elect code, and you are not allowed by code to load a continuous load circuit to more than 80% of capacity, thus a 20 amp circuit is max at 16 amps and a 15 amp circuit is maxed at 12 amps. Use the amp rating on the fixture data plate or the ballast of the fixture to calculate this.

Ground wires need to be screwed to each fixture, and you need to scrape off paint and get a good contact to the steel at each ground screw. You will have problems if you don't. Don't know why, but poor grounds are a contributor to why flo lights won't light up sometimes. I've seen it and others on this board have also mentioned that they too have experienced this.

Indeed, code requires a neutral at the switch now, so take your hot/neutral/ground to the switch box first and then up to the fixtures. Do NOT strip wire out of Romex, use the proper THHN wire, as it is properly marked. Flo fixtures get HOT so be sure and use 90°C rated wire or better. All of the THHN I've ever seen has this rating and is stamped right on it.

Charles

What he said.

Can you even get wire with insulation rated less than 90C these days? I think NM-B which is all the Romex that's sold is 90C (really old Romex that is only marked NM is probably 60C or thereabouts) as is any THHN I've ever seen.