Growroom Electricity and Wiring

[qbert]

I'd find some way to old work some new 12/3 romex on a 20A double pole breaker(at the main panel) to the wall receptacle you are using. I know it's a common hallway and all, but try to pick a time when you think no one will be around. Having Brand new 12/3 romex runing to a spec grade new 14-20R receptacle along with something like the above box with a 15A single pole GFCI breaker might be kinda sweet.

This would be ideal, I know. I'll have to see who I know that's an electrician. Pretty sure I could pull off arranging it when no one would notice. 240v isn't needed, but a 20a circuit would solve the problem of where to run my bedroom ac in the summer since half the apt is on that one circuit. Even though it will only run the cab and a couple cfl hallway lights, when I need that AC there isn't another circuit close enough and I'm sure one 15a will NOT handle the cab and AC.

I'd shut the breaker off to that receptacle and see just what kind of wire feeds it. If it's 2 old dirty black cloth wires coming into a black metal box, then I wouldn't feel overly good about using that wiring for my grow.

You're right, I should do this. Most of the wire I've seen in this building is that old cloth insulated stuff - pretty ratty looking too. When I asked the landlord about this unit she was fairly sure she had electricians in about a decade ago upgrading things to code, but when we moved in there was a GFCI kitchen outlet wired wrong - the kitchen was one area she specifically said was worked on (landlord botched the outlet, not the electricians) - but the wires were old and crusty.

 

[growclean]

I missed your post... Congrats.

Individual #2 AL conductors in conduit is only rated for 90A. They do make 90A breakers. Your over fused by 10A but really it's not too big of a deal. You've also slightly gone over the allowed conduit fill for 1" schedule 40 (Annex C of the NEC). But..... A for effort. You came pretty close. You also only needed #6 AL for the grounding conductor (250.122). Nothing wrong with overkill, just makes the conduit more full.

I'm going to assume you used individual conductors inside the conduit and not SER cable or anything. If you ran SER cable inside conduit, your going to have some serious heat issues and it would need to be pulled and redone..

Annex C in the Back of the NEC is really important when running in conduit because the conductors need to dissipate heat under load. They do that by the surrounding air. If you jam pack a 1" pvc conduit full of wire, you're going to do some insulation damage over time because the wires will get too hot in there.

Madpenguin<

Ok, in regards to my post: we are only using 40 amps at most right now. I am seriously bummed to here about the SER thing though, because that IS what we ran I think (all in one bundle?). I thought we were doing the "right" thing. Which only probably adds to your frustration lately.... sorry...

I do want to say that if at all possible, please don't stop helping! I know that you get "dumb" questions that are asked over and over again, and are answered OVER and OVER again. But truly, we all need YOU, and that means everyone like YOU that has specialized knowledge and can answer these type of questions. You are appreciated!!!!!

Two things to consider:

1. This entire site sucks for stickies: Can you update the first post with many of the FAQs? I know that I always start reading in a thread like this and get lost after 7 pages of formulas, calculations, and questions that don't apply to my situation. If the 1st page was an updated page with fresh links and updates it might cure the endless repeat.

2. Also, I am not sure where you live, but have you ever considered marketing yourself in this area specifically? If you are in a med state, what about creating a "grow-room" consultant business with a new name and marketing to and inside of hydro shops? Maybe team up with a GC and do the whole projects? Maybe you have more than enough business, but I was just thinking...!

Anyways I hope that you don't back away, think about what WOULD happen without you!!.....

 

[madpenguin]

Madpenguin<

Ok, in regards to my post: we are only using 40 amps at most right now. I am seriously bummed to here about the SER thing though, because that IS what we ran I think (all in one bundle?).

Yea... I had a feeling. That's why I mentioned it. You should only run individual conductors inside conduit. About your only exception is when you need to protect a piece of romex that comes down your basement wall to a receptacle. Then you can run romex for a short distance in conduit, but thats purely to protect the romex sheathing and conductors within from damage. 338.10(B)(4)(A) points you to 334.80 which states that any type SE cable ran indoors is to be used at the 60 degree Celcius rating. If you hunt down table 310.16 in this thread, that means indoor AL #2 SER is only rated at 75A. Seeing as how you've ran it in conduit, I would probably put a 50A main breaker on it max.

How the hell did you fit #2 SER in 1" PVC anyway? I don't even know if I'd feel good about having a 50A main on it. You really should bite the bullet and yank it.
Some #2 XHHW or THHN would be good for 100A if they were individual conductors and ran in conduit. That's copper mind you, not Aluminum....

1. This entire site sucks for stickies: Can you update the first post with many of the FAQs? I know that I always start reading in a thread like this and get lost after 7 pages of formulas, calculations, and questions that don't apply to my situation. If the 1st page was an updated page with fresh links and updates it might cure the endless repeat.

Philthy and I have PM'ed about it before. It's just a matter of taking the time to hunt down all the info and itemize it into an linkable index.

About #2, I'm not in a med state.

I'll try to make an index soon. I know it's a bitch trying to read this entire thread.

 

[growclean]

Yea... I had a feeling. That's why I mentioned it. You should only run individual conductors inside conduit. About your only exception is when you need to protect a piece of romex that comes down your basement wall to a receptacle. Then you can run romex for a short distance in conduit, but thats purely to protect the romex sheathing and conductors within from damage. 338.10(B)(4)(A) points you to 334.80 which states that any type SE cable ran indoors is to be used at the 60 degree Celcius rating. If you hunt down table 310.16 in this thread, that means indoor AL #2 SER is only rated at 75A. Seeing as how you've ran it in conduit, I would probably put a 50A main breaker on it max.

How the hell did you fit #2 SER in 1" PVC anyway? I don't even know if I'd feel good about having a 50A main on it. You really should bite the bullet and yank it.
Some #2 XHHW or THHN would be good for 100A if they were individual conductors and ran in conduit. That's copper mind you, not Aluminum....

Yeah.... we thought we were doing something good by running it in that conduit... It looks SO clean that way. So as a "quick fix" should I just pull the conduit and leave the SER bare and strap it directly to the wall? Then lower our total amperage? Walls are rocked now, so I would rather not pull the wire, especially since we don't actually need the 100amp. We thought we were going overkill on everything to protect ourselves. In regard to fitting it in that conduit.... it wasn't that bad except the "elbow joints" that lead into the wall at either end. They were a BITCH! From there everything is individual wire because that is the only way I could get it through! So conduit is only OUTSIDE the walls.

 

[madpenguin]

From there everything is individual wire because that is the only way I could get it through! So conduit is only OUTSIDE the walls.

That confuses me a little. Are you saying that inside the walls you ran conduit along with individual wire in the conduit and you somehow spliced SER onto the individual conductors at the elbows?

Or, there is no conduit inside the walls? Is it SER from panel to panel with the only conduit being on the outside of the walls to protect them?

Well, at any rate. That cable assembly is only good for 75A. Nipples (A piece of conduit 24" in length or shorter) used to be ok to run wire through without de-rating, but with 2008 code, I believe that is not the case anymore.

It sounds as if you need to put a 50A main breaker on that feeder cable. Did you somehow splice individual conductors onto SER cable?

 

[growclean]

Sorry for the confusion. The SER is one piece from panel to panel, with the conduit only being used outside the walls. When it runs inside the walls into the panels, I had to cut away the "sheathing" that surrounds all 4 wires (they are still sheathed indivually). I hope that makes sense.
We will put in a smaller breaker though! Thanks for the catch.

 

[madpenguin]

Sorry for the confusion. The SER is one piece from panel to panel, with the conduit only being used outside the walls. When it runs inside the walls into the panels, I had to cut away the "sheathing" that surrounds all 4 wires (they are still sheathed indivually). I hope that makes sense.
We will put in a smaller breaker though! Thanks for the catch.

Any and all parts of the SER cable has to be completely sheathed when inside the walls. Still having a slightly hard time understanding, but whatever. Using conduit to protect the SER is a good idea but you need to use something upwards to 2" PVC to sleeve it where it comes out of the wall and up into the panels.... You always want atleast 3/8" of outer sheathing to extend into each panel as well.

That cable needs breathing room to dissipate heat. That's why when you bundle lots of romex together, you need to start derating the amperage that each of those wires will see. Same situation with running SER cable inside conduit. The cable was meant to run "free-air" and dissipate heat that way. By you jaming it into a tiny 1" conduit, it's really going to heat up if you put more than 40-50A on it.

The ideal thing to do would have been to run 1 1/2" PVC from panel to panel and then fish individual conductors through the conduit. Conductors that are rated for the main breaker that you attached them to. Again, Table 310.16 is used for feeder cables to sub panels and branch circuits. Table 310.15(B)(6) is only used on SEU coming out of the meter and straight into your main panel.

If the cable in question does not serve the entire load of the dwelling, then Table 310.16 must be used to size wire. Again, that table is here in the sticky.

I'll try to get some sort of index up and running on the first page.

 

[FreezerBoy]

I'm trying to reduce my reflectors footprint by removing the "junction Box" and securing the wires inside the reflector housing. I notice that once the cord comes into the box, it pigtails with braided, high temp wire for the last 4-6 inches of the run to the socket. Is that a safety feature with which I should not play? Do I need them? What do they accomplish?

FWIW, while originally purchased with a 150 HPS, the ballast box is clearly marked as a 1K and the hood is obviously made for a larger lamp than my current 250 CMH. I believe they took a 1K system off the shelf and refitted it to a 150.

 

[richyrich]

I have a quick question for you guys. I have done several of my own wiring set-ups, but right now I am having a serious brain fart--damn xanax.

I moved into a new place and the garage is already wired with a sub panel. I looked in the main panel and they attached a double pole 50 amp breaker to 8 gauge wire. I have two questions.
1. Shouldn't the breaker be 40 amp max?
2. How many amps can this panel handle right now, 40 amps or 80 amps? If I ran everything at 120, would i be getting 80 amps total out of the sub panel because each leg holds 40 amps coming out of the main panel?

 

[richyrich]

^ Service panel 200 amps. Main panel with 50 amp double pole breaker going to sub panel. The wire is 8 gauge to sub panel for sure. Run to sub panel is about 50 feet.



^ Sub panel has (1) 30 amp double pole breaker, (1) 15 amp single pole breaker and (2) 20 amp single pole breakers.



^ Inside of sub panel.

Currently, the only load on this is an electric dryer--I think uses 20 amps at 240 (not sure, can someone chime in on this), and a washing machine.

I plan on running (4) 600 watt ballasts at 240, (1) split a/c that draws 12 amps at 115, (3) 6" inline fans at 120, a dehumidifier that draws 4.5 amps at 120,and accessories totaling around 3-4 more amps at 120.

Do I have enough out of this sub-panel? Do I need to make any changes to breakers or wire gauge? Pointers and advice appreciated.

 

[madpenguin]

it pigtails with braided, high temp wire for the last 4-6 inches of the run to the socket. Is that a safety feature with which I should not play? Do I need them? What do they accomplish?

Yea, Looks to be braided conductors. Serves the same purpose underneath the hood of a car by dissipating heat (it also looks nice when in chrome). That's a tough call. You could probably direct wire it without the conduit body but I'd check on those conductors every couple days to see how they are faring. Any brittle or brown spots and you should cut those off and wire it back up the way it was.

Or try to pull the braids off the conductors if they are somehow loose and slide them over your flexible cord conductors.

 

[madpenguin]

I looked in the main panel and they attached a double pole 50 amp breaker to 8 gauge wire. I have two questions.
1. Shouldn't the breaker be 40 amp max?

That depends on whether it is #8 copper romex feeding the subpanel or whether they are individual conductors that run in conduit the whole way to the subpanel. Look at Table 310.16 here in the sticky. Romex and SE cable is rated for 60 degrees Celsius and the 75 and 90 degree columns are for individual conductors in conduit.

2. How many amps can this panel handle right now, 40 amps or 80 amps? If I ran everything at 120, would i be getting 80 amps total out of the sub panel because each leg holds 40 amps coming out of the main panel?

40A.... 40A at 120v or 40A at 240v. If the breaker says 40 on the handle then that's all it's going to handle.

 

[richyrich]

I figured out I have 40 amps total to my subpanel. That 50 amp breaker in the main needs to be changed to 40. I measured the dryer while running with a snap around meter and it is drawing 23.5 amps. I am going to install an intermatic timer on the dryer so it does not run during the night when most of my grow equipment is running.

 

[richyrich]

That depends on whether it is #8 copper romex feeding the subpanel or whether they are individual conductors that run in conduit the whole way to the subpanel. Look at Table 310.16 here in the sticky. Romex and SE cable is rated for 60 degrees Celsius and the 75 and 90 degree columns are for individual conductors in conduit.



40A.... 40A at 120v or 40A at 240v. If the breaker says 40 on the handle then that's all it's going to handle.

Thanks madpenguin. I was wrong about it being romex. They are individual 8 gauge wires. Does that make any difference with anything? I'm going to look for the table right now.

 

[madpenguin]

^ Service panel 200 amps. Main panel with 50 amp double pole breaker going to sub panel. The wire is 8 gauge to sub panel for sure. Run to sub panel is about 50 feet.



^ Sub panel has (1) 30 amp double pole breaker, (1) 15 amp single pole breaker and (2) 20 amp single pole breakers.



^ Inside of sub panel.

Currently, the only load on this is an electric dryer--I think uses 20 amps at 240 (not sure, can someone chime in on this), and a washing machine.

I plan on running (4) 600 watt ballasts at 240, (1) split a/c that draws 12 amps at 115, (3) 6" inline fans at 120, a dehumidifier that draws 4.5 amps at 120,and accessories totaling around 3-4 more amps at 120.

Do I have enough out of this sub-panel? Do I need to make any changes to breakers or wire gauge? Pointers and advice appreciated.

I'll post back in the AM. It looks like it might be a conduit run the whole way but I'm not sure. Double check on that will ya? If those brown conductors are in conduit the whole way back to the main panel and they are indeed #8 CU, then yes, they are rated for 50A.

But they are backfeeding a 30A DP main, which is kinda stupid as well as saying that your garage might be a detached structure. There was no need to back feed a 30A DP breaker for a main disconnect in the garage subpanel unless the garage is detached from the house. And why it's a 30A and not a 50A is beyond me....

Again, I'll post back in the am. It's getting late.

EDIT: oh.. never mind. You have 2 red conductors feeding you sub. the brown wires are load out for your dryer. I'll post back in the AM

 

[richyrich]

I'll post back in the AM. It looks like it might be a conduit run the whole way but I'm not sure. Double check on that will ya? If those brown conductors are in conduit the whole way back to the main panel and they are indeed #8 CU, then yes, they are rated for 50A.

But they are backfeeding a 30A DP main, which is kinda stupid as well as saying that your garage might be a detached structure. There was no need to back feed a 30A DP breaker for a main disconnect in the garage subpanel unless the garage is detached from the house. And why it's a 30A and not a 50A is beyond me....

Again, I'll post back in the am. It's getting late.

EDIT: oh.. never mind. You have 2 red conductors feeding you sub. the brown wires are load out for your dryer. I'll post back in the AM

Great 50 amps. It is #8 CU. I was poking around in there today and got a better look at everything. Yeah, that 30 amp breaker in the sub panel is just the breaker for the electric dryer. Somebody wrote main with marker. Maybe they were on xanax like me, lol. I was brain farting bad yesterday. My wiring knowledge is coming back. Thanks again.

 

[richyrich]

The print on the wire says "type THWN-2." Looked at the chart and my wire is good for 55 amps.

 

[madpenguin]

The print on the wire says "type THWN-2." Looked at the chart and my wire is good for 55 amps.

Not so fast....

While THWN-2 is rated for 90 degree Celsius, Your terminal lugs and breaker lugs are only rated for 75 degree Celsius. That means it's only good for 50A (the 75 degree column).

Plus, that's only if they are individual conductors which are ran in conduit the entire way from main panel to sub panel.

 

[chongsbuddy]

what does a baseboard heater run on 120 or 240?

what does a baseboard heater run on 120 or 240?

I just closed in my grow room,its 4 by 8,and in it i just took out a baseboard heater and marretted the wires.What amp do you think this is?is there a way to find out?would this mean i could just run a subpanel off this?my buddy said i probably could,he said its prob a 30 amp 240.can anyone help me out with this?maybe help me figure this out?it woiuld save some money putting a new breker in my main and then running 8/3 wire to my grow room.

 

[richyrich]

Not so fast....

While THWN-2 is rated for 90 degree Celsius, Your terminal lugs and breaker lugs are only rated for 75 degree Celsius. That means it's only good for 50A (the 75 degree column).

Plus, that's only if they are individual conductors which are ran in conduit the entire way from main panel to sub panel.

Gotcha. Yeah, I have individual conductors ran through conduit the entire way to the sub-panel in a detached garage. Thanks.