Growroom Electricity and Wiring

[madpenguin]

Let me start by asking if it would be wise to utilize a 'sub-panel' or a second breaker box altogether when setting up a new room.

Well, those are pretty much one and the same.

It isn't likely that I will have enough slots in my primary breaker box to add circuits even though there are some open. I will start initially w/ 2x 1000W units, to eventually expand to 4x 1000W systems over the next year from the initial time of building out. Also, 400W system and a 4x 4' T5 fixture. The other high wattage items will be a split A/C (12K-15K BTU), space heater, dehumidifier and Charcoal filtration unit. The rest will all be peripheral equipment not exceeding 3K watts (ie, fans, Sulphur burner, pumps, CO2 monitor/burner, light mover, ozone machine, and eventually a 1/4 HP chiller). I would like to wire 120V, as the majority of equipment will be compatible (obviously US res). I just have no idea where to start? Can you point me in the right direction to some good resources, addtl threads of yours, etc? I trust your judgement, references, and recommendations. Thank you in advance, it is much appreciated.

I know how you feel regarding utilization of trained technicians, and plan on having it inspected by such, however I would like to complete the labor myself.

Well, I just added up 13kw at 120v... That's 108A and derated to 80% wire capacity puts you at 135A. 2/0 copper SER cable on a 150A double pole breaker is what you would need.

I think your going to need a service upgrade.... I'll do it for 2k. I'll do the subpanel for an additional 1k...

Seriously, Run all your lights at 240v. If you haven't bought the split unit, look for one that's 240v. Try to run as much as possible at 240. The space heater and dehumidifier alone will draw more than 20A at 120v... You fight an uphill battle on a good sized op such as the one your planning using only 120v.... If your house has a 400A service, then sure... You might have room to spare for all that at 120v.

Do some research on new equipment and then come back with a new attack plan and I can point you in the right direction.

 

[madpenguin]

So. I have a 200 amp panel that looks pretty full, I'm wondering how big of a sub panel i can add.

That really depends on your current load demand for the house. As in, how much amperage you already use for stoves, microwaves, fridges and the like.

There is a 60amp 220 breaker that leads 70 feet to the other end of the house and down for the power to the old outside hottub.

i want to take this line directly down into the basement into the grow area and install a sub panel.

Sounds like the work is already done for the most part. gotta love existing wiring. Just inspect it the whole length and make sure it's in good shape.

How do I figure out the biggest sub panel I can install? How much do i need for 2500watts of lights then all the fans, humid, pumps etc etc

Well, you can install as big of a subpanel as you want as long as it's rated for atleast 60A. You just have to use that existing 60A double pole breaker back in the main to protect it. So.... You'll have 60A to work with. With your equipment above, you have lots of room to spare.

Looks like most of the work is done for me just need to terminate it properly. The cable is really thick but couldn't see the writing when i pulled the insulation away in the spa room. Do all cables have writing on them?

Yea, they should. I would venture a guess that it's #6 AWG copper, but never assume anything. Look really close at the outer sheath. There should be writing somewhere.

Um... How many conductor's does it have? Just a black, white and a bare? If so, your short a wire.

 

[jyme]

it was a 4wire cable.outdoor type i put it in a conduit.the wire was #6 rated for 55a per wire the red and black.the white neutral,and a bare ground.so i need to change my 20a down to a 15a ok thanks i will and im gunna go reed the post. why cant the #6 cable carry 55a thats what its rated for at the store. im not disagreing in currious. and im noyt using a breaker im wiring in under a 200a main. is there somthing wrong with this?

 

[jyme]

so i will need to get a 100a breaker and use it will it hold my copper #6 55a wire?

 

[GeorgeSmiley]

Yea, they should. I would venture a guess that it's #6 AWG copper, but never assume anything. Look really close at the outer sheath. There should be writing somewhere.

Um... How many conductor's does it have? Just a black, white and a bare? If so, your short a wire.

Found a little writing on the parts i can see and it looks like 6-3 and 600v?

 

[GeorgeSmiley]

So I should install the subpanel in the basement and pull the wire down from the spa to the panel. The wire is 6-3. 60 amp panel with 2 220v outlets for flower and 1 220v for the veg side. The grow area is 6ft wide x 12 feet long. I need 4 110 on the veg 4 110 on the flower side and 4 in the middle.

If I have this right, every 6 feet i need an outlet and I think I want them 48" from the floor?

How many circuits will I need for the 110 and 220? I'm not sure how it should be wired so every 6 feet I have 4 110 plugs and 2 220 on each side. The box will have to be at the far end so the runs would have to be around the perimeter to the other side.


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[madpenguin]

and im noyt using a breaker im wiring in under a 200a main. is there somthing wrong with this?

Ah shit man... You double tapped your lugs at the main panel?

Dude, you have to stab that wire onto a 60A double pole breaker that will be in your 200A main panel. You've got unfused wire running throughout your house. Bad news.

And just because each wire is rated to handle 55A doesn't mean you can use a 110A breaker. That is a common misconception of the average person who doesn't know about breakers or electricity. When you reach a total of 60A between both the red and black wires the DP 60A breaker will trip. You could be pulling 60A on the red wire and 0A on the black wire, or 30A on both wires. Eitherway, if you slap a 100A DP breaker on that #6 (rated for 55), you could pull 90A down just the red wire and the breaker will not trip. Do you see where I'm going with this? That red wire is going to be seriously over loaded. That's why you have to use a 60A breaker on 60A rated wire. (The NEC allows you to use a 60A breaker since there is no 55A breaker).

The cable assembly is rated for 55A, not the individual wire. Just look at it like that. And please don't double tap shit like that. 10:1 those lugs aren't rated for it plus all that feeder cable is unfused. Great way to catch your house on fire.

 

[madpenguin]

So I should install the subpanel in the basement and pull the wire down from the spa to the panel. The wire is 6-3. 60 amp panel with 2 220v outlets for flower and 1 220v for the veg side. The grow area is 6ft wide x 12 feet long. I need 4 110 on the veg 4 110 on the flower side and 4 in the middle.

If I have this right, every 6 feet i need an outlet and I think I want them 48" from the floor?

How many circuits will I need for the 110 and 220? I'm not sure how it should be wired so every 6 feet I have 4 110 plugs and 2 220 on each side. The box will have to be at the far end so the runs would have to be around the perimeter to the other side.


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Yea, I'd pull the wire down into a subpanel. It can be a 125A MLO panel. As long as the subpanel is in the same structure as the main panel, you don't have to have a main breaker at the subpanel. You still adhere to the 6 throw rule because all you have to do is throw one breaker back at the main and that entire panel is dead.

BTW, the 6 throw rule says you have to be able to de-energize everything fed from that panel with 6 throws of the hand. That would mean 6 breakers. But you'll have one breaker controlling the entire subpanel back at the main, so buy as big of a subpanel as you need. Get a MLO panel and terminate the conductors directly to the lugs.

The NEC says you need a receptacle every 12 feet but there is nothing prohibiting you from putting them closer. You can put them at whatever height you want as well. If I'm not mistaken, somewhere around 6 feet is the maximum height. Industry accepted standard is about hammer height, but do what ever you want.

It really depends on what the total load is as far as how many circuits you need. For a 15A breaker, don't exceed 12A and for a 20A breaker, don't exceed 16A.

So, you'll just have to find out how much your appliances draw amp wise and go from there.

And, yes. #6/3 copper is what you want to feed a 60A subpanel. Well, you can feed a 125A Main Lug Only panel as I said earlier, but you have to use a 60A double pole breaker at the main panel, which really only gives you 60A....

 

[GeorgeSmiley]

The 6-3 comes from a double pole 60A at the main panel.

Is it better to have another 60a main in the sub panel? MCB?

What about outlets in the ceiling?

I'm going for no extension cords, no power strips, smoke detector and fire suppression eventually. Want to get the wiring right first time.

I'll do some homework and get the load numbers off of stuff.

 

[madpenguin]

it was a 4wire cable.outdoor type i put it in a conduit.

Also, you can't put a cable assembly in conduit. Only individual conductors. If it was a 4 wire cable asembly rated for direct burial, then you should have just buried it following the burial depth chart I posted here on this thread.

Because it's cable in conduit now, it's not going to be able to disperse heat like it was designed to do and therefore may need to be derated to carry less than it's maximum capacity...

 

[madpenguin]

The 6-3 comes from a double pole 60A at the main panel.

Is it better to have another 60a main in the sub panel? MCB?

You can backfeed a 60A double pole breaker in your MLO subpanel but that's only if you want a main disconnect right there in the grow room. Otherwise, it's really not necessary. Your main disconnect is already considered to be the 60A breaker back at the main.

What about outlets in the ceiling?

Ummmm...... That's a really good question. I want to say the NEC doesn't allow it tho I'm not sure. You can do it if you want, as long as it's not getting inspected but you might have to worry about the wieght of the cord pulling itself out of the receptacle..... So, you might want to fasten the gang boxes so they point horizontal instead of down.

I'm going for no extension cords, no power strips, smoke detector and fire suppression eventually. Want to get the wiring right first time.

That's a good idea. I'd run interconnected smokes with 14/3 and old work one in upstairs somewhere so if the grow room alarms go off, you can hear the solo one you punched in upstairs go off as well. I grow in an attic so that what I did with my room. One interconnected smoke in the grow room and another one in my dining room that I can hear no matter where I am in the house. If that goes off, I know to high tail it to my grow room quick.

I'll do some homework and get the load numbers off of stuff.

Sounds good.

 

[GeorgeSmiley]

If this is too many questions then I can save them up till I get a bunch


I think it would just be a rather simple step for me to actually pull a permit and get an inspection when I'm done. The city is really good to work with unless your a tard or didn't pull a permit.

Do hard wired smoke detectors have a battery backup?

What happens to all the electrical circuits if the fire suppression system kicks off?


Do I need a GFCI anywhere?

 

[jyme]

Also, you can't put a cable assembly in conduit. Only individual conductors. If it was a 4 wire cable asembly rated for direct burial, then you should have just buried it following the burial depth chart I posted here on this thread.

Because it's cable in conduit now, it's not going to be able to disperse heat like it was designed to do and therefore may need to be derated to carry less than it's maximum capacity...

hum,very interesting thanks man.

Wrong. That #6 cable can't have anything higher than a 60A Double pole breaker feeding it. Once you hit 60A total, the breaker will trip.
so i also need to get a double 60a one thats conected on the trip where if one side flips both do.and that will ensure my 200amp main feeds my 100a indoor sub panel that has a built in 100amp breaker is properly feed?
so when i hook my wires in i need my black wire on one side of the 60a and the red wire on the other side of the 60a ofcourse its a double pole 60a so that makes a combined amperage of 120amps running to the 100amp main box?

 

[madpenguin]

hum,very interesting thanks man.

so i also need to get a double 60a one thats conected on the trip where if one side flips both do.and that will ensure my 200amp main feeds my 100a indoor sub panel that has a built in 100amp breaker is properly feed?
so when i hook my wires in i need my black wire on one side of the 60a and the red wire on the other side of the 60a ofcourse its a double pole 60a so that makes a combined amperage of 120amps running to the 100amp main box?

You can use a 100A Main Breaker Panel for your sub like your doing but if your using 6/3 copper cable then you need to protect that cable upstream with a 60A Double Pole breaker in the main panel, yes.

And, once more, no..... You don't have a combined amperage of 120A. Your using a 60A Double pole breaker. You have a total of 60 amps period. Just get that out of your head. It doesn't matter that it's twice as wide as a regular breaker. It doesn't matter that it says "60" on the handle twice. It will trip at 60A just like a single pole 60A breaker will trip. 60 amp. That's all you have. Period.

If you wanted the full 100A for that MBP in your grow, then you needed to use #2 copper or 1/0 aluminum fed by a 100A double pole breaker in the main panel.

Again, check Table 310.16 that I posted here in this thread.

 

[madpenguin]

I think it would just be a rather simple step for me to actually pull a permit and get an inspection when I'm done. The city is really good to work with unless your a tard or didn't pull a permit.

You can do that if you want. It's around 150 per inspection. If your finishing with drywall then you'll need one for the rough-in and one for the final inspection.

Do hard wired smoke detectors have a battery backup?

Yes. And they are loud as fuck.

What happens to all the electrical circuits if the fire suppression system kicks off?

Nothing. Not unless the fire suppression system is designed to kill power to the panel when it trips. Depends on how wet things get. Romex is exposed to weather all the time on job sites until the building is completely weather proofed. The outer sheathing can get wet but if you get water down in the sheathing, you'll know about it when the power comes back on. The cable will literally blow up. It's kinda cool as long as it happens in a controlled environment, which behind walls is NOT a controlled environment.\

I had a roll of 12/2 that got submersed in water. tied one end into my basement panel and hooked a receptacle up to the other end. Plugged in a space heater and turned it on. Went to the panel and turned the breaker on. It'll give you a heart attack. The wire literally explodes and makes a large "bang". Fun stuff.

Do I need a GFCI anywhere?

Technically within 6 feet of an open water source or in an exposed/unfinished basement (concrete floors). I posted the NEC requirements on GFCI's somewhere in this thread. I also posted AFCI requirements as well.

If you get inspected make sure you know what your doing. If you staple the cable 12 1/2" from a gang box, he can fail you and then you need to pay another 150 for him to come back out. You really have to know your code if your going to get inspected.

 

[GeorgeSmiley]

Does the sub panel have to be between some studs or can it be attached to the concrete wall?

Inspection fees are $79 each and as far as I can tell the permit is around $100. Not too bad

 

[madpenguin]

Does the sub panel have to be between some studs or can it be attached to the concrete wall?

It can be either or. If you mount it between 2 studs, it needs to be flush with the exterior surface of the drywall. The front edge anyway. If given the choice, buy some 3/4" plywood. The 3 or 4 ply stuff and masonry screw that to the concrete wall. Then mount the panel to that. Makes running branch circuits a breeze. Now and in the future. If you flush mount the panel now, you have to fish new circuits to it. Big pain.

Just make sure you use #14 on a 15A breaker and #12 on a 20A breaker. Cables fastened within 12" or less of each gang box and every 4 feet thereafter. Actually, I think it's 4 1/2 feet. No sharp angles with your cable, just gradual bends. No more than 3 cables per 3/4" hole. Cable 1 1/4" from the face of the framing members. Nothing smaller than a 8/3 or a 6/2 on the bottom of exposed basement joists.... Don't drill holes in the middle 3rd of the joists length wise between either load bearing wall. Just the 1st 3rd out from each wall. Drill dead center from top to bottom of a joist and not in the top or bottom 3rd vertical wise. Atleast 6" of conductors from the point where the cable enters the gang box.

You know, I already listed all this stuff throughout this thread. If someone were so inclined, all they would have to do is read and then absorb this thread and they would be doing better than most electrical subcontractors as far as meeting code....

Make sure you make up your grounds before the rough inspection else they might fail you. They like to see that all your grounds are barreled and crimped together with just enough leads for the devices going in said box. Might as well make up all your neutrals while your at it. Curl your left over hot wires into pigtail looking curly cues and you'll impress the inspector and he'll more than likely leave you alone.

Make your panel look REALLY neat. Make sure you keep the neutrals and grounds isolated. Use the top knockouts only. All wires coming down either side in a straight line and then have them make an abrupt 90 to land at the breaker or neutral buss.... You can even take a piece of sheathing and write on it what the branch circuit feeds and slip it over the hot conductor before you attach it to your breaker. If it's #14 wire, then use white sheathing to write on. If it's #12 conductor, use a piece of yellow sheathing to write on. Keep the sheathing with writing horizontal right after the breaker lug.

This way you can tell exactly what every circuit is and what amperage it is without having to get up close or hold the front panel up to the enclosure. An inspector will take one look at that and know your an anal bastard, thus not spend as much time scrutinizing your work.

Inspection fees are $79 each and as far as I can tell the permit is around $100. Not too bad

That's not too bad. You must not live in a big city....

 

[jyme]

You can use a 100A Main Breaker Panel for your sub like your doing but if your using 6/3 copper cable then you need to protect that cable upstream with a 60A Double Pole breaker in the main panel, yes.
so i will not have 100a running to my 100a indoor sub-panel or will i?
If you wanted the full 100A for that MBP in your grow, then you needed to use #2 copper or 1/0 aluminum fed by a 100A double pole breaker in the main panel.
so i need to go buy new wire again that sucks copper is high?
and then will i still need the 60a dp or can i double tap it?

 

[GeorgeSmiley]

I'm in a big city.

I am reading through the entire thread, I really appreciate everyone's effort to make sure we can do some of this stuff safely.

Thanks for the quick rundown on the basics of what I need to do along with studying.

I wired my woodshop at my old house and it was great, and all the wiring was safe but some aspects wouldn't have passed code such as bare romex in a few spots.

Want to do it right,

Thank you

 

[madpenguin]

I wired my woodshop at my old house and it was great, and all the wiring was safe but some aspects wouldn't have passed code such as bare romex in a few spots.

Yea, can't have exposed romex until you hit a height of 8 feet, otherwise it has to be sleeved with conduit.

Sounds like you already know a bunch of stuff. Keep us posted on your project.