15 amp or 20 amp or 2 15 amps? 4X8 tent two led lights

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Sparky75

Sparky75

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Looking at all the variables down the road is a 15 amp suffice to run a 4x8 tent with two 900w led lights @4.5 amps and everything else. If I tried hydro later and all the gadgets are 15 amps, not enough. I want to set it up right the first time and not have to run another box later. So am I safe with a 15 amp or a 20 amp or should I put 2 15 amp plugs so I have plenty for any gadgets I may add later? Thanks.

4X8 tent
2 900w led (4.5 amps each)
fans
UVB lights later
humidifier
possible A/C
anything else that is normal in a grow tent that requires power.
 
greenscholar

greenscholar

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Correct, I have a 8x8 room 1200 watts of led and I have both lights on the 20 amp than I leave the 15 amp for my fans and occasionally add a light in that room.
 
Sparky75

Sparky75

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Correct, I have a 8x8 room 1200 watts of led and I have both lights on the 20 amp than I leave the 15 amp for my fans and occasionally add a light in that room.


That is what I was thinking. I read about power surges if everything is on one outlet and it is better to have lights on one and everything else on the other because those things are always kicking on and off. I don't know. But it is logical.
 
cemchris

cemchris

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Amp everything out that you listed and want to potentially add later and go from there. Guessing will only cost you money in the end. Nice thing about electronics is pulling the requirements is pretty simple. Just add it all up and give yourself the proper headroom. 15 amp circuits will always be cheaper then 20's wire wise. All depends on how long the runs are gonna be.

From everything you listed you will need at least 2 circuits at a min.
 
Sparky75

Sparky75

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Amp everything out that you listed and want to potentially add later and go from there. Guessing will only cost you money in the end. Nice thing about electronics is pulling the requirements is pretty simple. Just add it all up and give yourself the proper headroom. 15 amp circuits will always be cheaper then 20's wire wise. All depends on how long the runs are gonna be.

From everything you listed you will need at least 2 circuits at a min.


50-75 feet.
 
basscaptain

basscaptain

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your going to want that 20 for the ac........ everything else will run on a 15 but since your running it go with 2 20....... better to be safe then sry down the road........ in the big pic your talking 100$ it's nothing in the long run.........

I would run 3 if it was me

20amp/ ac
15 amp lights and etc....
15 amp hum and fans

Not the place to start out cheap.... it's alot easyer to spend the extra 100$ now then later...... you can NEVER have to MUCH Juice......
 
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Sparky75

Sparky75

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Why not run 1 240V line (using no.6 wire) to a sub panel? That should be fine for 50 Amps. From the sub panel you could wire up (1) 20A and (2) 15A breakers to separate outlets.


I am running from a subpanel in the basement. I will look and see how big that subpanel is or if I can just run another subpanel down in the basement from the main power supply. That would be best so the power is already there for any extra little things in the basement. Thanks.
 
cemchris

cemchris

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I am running from a subpanel in the basement. I will look and see how big that subpanel is or if I can just run another subpanel down in the basement from the main power supply. That would be best so the power is already there for any extra little things in the basement. Thanks.

50 amps is way overkill for 1 tent. Unless you plan on adding in more tents or more lights later on. I run 40 amp 220v subs to each of my 2 rooms with 2 - 1ks and branch off the 110v for them for each and still have headroom. I could have gone smaller but I had the wire already. 1 A/C on a diff circuit for everything.

I am in agreement with run it once but unless you plan some serious upgrades later this will be the most expensive route to take and pretty overkill.

100ft of 14/2 is around half the cost of 12/2 give or take. Unless you plan on running 220 ( then u run 3 wire not 2)and splitting off 110 at the tent, then if you can get away with 2 -15 amp circuits vs 2 -20 amp circuits you will save. It all gonna depend on what amps you are gonna need with the A/C and what size fans you are running. Doubt the huey pulls that much like vs a dehuey. Fans don't really pull much of anything until you get up into 10/12in then you have to account for a couple of amps. Do the leg work on how much you are gonna need. Account for everything and give your self a little over head plus the safe overhead on the circuit for any unexpected add ins later on.

This is also gonna come down to how much room you have in your subpanel in the basement. I have a full panel 100 amp drop downstairs so I don't have to be as concerned with breaker space. If I didn't I would have run 1 panel for everything. IMO an extra subpanel is way overkill for 2 - 3 circuits unless u plan on running 220 and 110 and hard wiring your timer(s) or you lack space in the panel or need more power in general downstairs. Even with that approach its almost always cheaper to just upgrade the current sub specially if they over sized the wire (which happens depending on how big the panel is). If you need to go this route and other things like HVAC ect are on that sub I would get an electrician to do it so its up to code or you are up on that stuff that way if you ever move you don't have to go through the headache of fixing the electrical before hand. Not to mention some places require you to pull permits for it.

100ft of 12/2 vs 6/3 is like 29 bucks vs 215 bucks just for the wire.
 
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Dan789

Dan789

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My two cents, depends on the length of any potential circuit being contemplated. As load, and length conspire to add voltage drop for any respectively sized circuit. As you add load, voltage will go down and increase the amperage necessary to accomplish the same work. Two 20 amp circuits (size #awg12), each 50 feet long will work fine with 15 amps load and only 2.8 volts drop. If those were 12 amps load, #awg14 wire circuits, the drop would increase somewhat as would the amperage available to use. Hope that helps you decide what will work best for you. Also keep in mind utilizing GFI'S and that aspect for personnel protection around any water potentially being introduced.
 
PipeCarver

PipeCarver

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My two cents, depends on the length of any potential circuit being contemplated. As load, and length conspire to add voltage drop for any respectively sized circuit. As you add load, voltage will go down and increase the amperage necessary to accomplish the same work. Two 20 amp circuits (size #awg12), each 50 feet long will work fine with 15 amps load and only 2.8 volts drop. If those were 12 amps load, #awg14 wire circuits, the drop would increase somewhat as would the amperage available to use. Hope that helps you decide what will work best for you. Also keep in mind utilizing GFI'S and that aspect for personnel protection around any water potentially being introduced.
Not so much with ac But with dc voltage there's a big drop in voltage if the wire's not big enough. I was an electrician for 30+ years 2 circuits 15 amp circuits is ample. The only reason to go to the added expense of a sub panel is to shorten the runs for large wires #10-#8-#6 and so forth not to keep #14 wire short. I'd run a 3 conductor #14 with a common neutral on 2 -15 amp circuits to a 4-11/16" junction box from there I'd drop down with 2- #14/2 cabtire / extension cords. with a 4x4" box and 2 receptacles in each box. Something like this crude map.
 
2 15 amp circuits
Dan789

Dan789

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Not so much with ac But with dc voltage there's a big drop in voltage if the wire's not big enough. I was an electrician for 30+ years 2 circuits 15 amp circuits is ample. The only reason to go to the added expense of a sub panel is to shorten the runs for large wires #10-#8-#6 and so forth not to keep #14 wire short. I'd run a 3 conductor #14 with a common neutral on 2 -15 amp circuits to a 4-11/16" junction box from there I'd drop down with 2- #14/2 cabtire / extension cords. with a 4x4" box and 2 receptacles in each box. Something like this crude map.
With that method, you legally (NEC) cannot control individuality each of those two circuits...
PS, not to start a pissing match, but I’ve got 40+ years IBEW/NECA experience, retired Electrical contractor.
 
PipeCarver

PipeCarver

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With that method, you legally (NEC) cannot control individuality each of those two circuits...
PS, not to start a pissing match, but I’ve got 40+ years IBEW/NECA experience, retired Electrical contractor.
I'm not sure what you're getting at ... 2 - single pole 15 amp breakers are separately controlled, I also worked in ship yards for many years and that was our go to method for maneuverable power supply. I'm not talking about a permanent receptacle mounted on studs or a 2pole 15 amp breaker with a removable bar between them. Not much different than a kitchen counter plug with 2 circuits in on one receptacle but on single pole breakers. IBEW 213.
I know shits changed over the past few years, I was out of construction & a maintenance electrician in a hospital for 10 years so new code has changed since then but the practicality of my wiring methods are sound code or no code. Check the steamship inspectors guide for confirmation lol,
 
Dan789

Dan789

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I'm not sure what you're getting at ... 2 - single pole 15 amp breakers are separately controlled, I also worked in ship yards for many years and that was our go to method for maneuverable power supply. I'm not talking about a permanent receptacle mounted on studs or a 2pole 15 amp breaker with a removable bar between them. Not much different than a kitchen counter plug with 2 circuits in on one receptacle but on single pole breakers. IBEW 213.
I know shits changed over the past few years, I was out of construction & a maintenance electrician in a hospital for 10 years so new code has changed since then but the practicality of my wiring methods are sound code or no code. Check the steamship inspectors guide for confirmation lol,
So here’s three initial problems with what you’re thinking and advising others without any experience (demonstrated electrical) to do:
1. NEC article 210.4; concerns multi-wire branch circuits (three wire, shared neutral per your sketch) All ungrounded conductors must be simultaneously disconnected by means of a permanent handle tie, ie in this case two pole c/b with permanent handle tie. No individual circuit control.
2. NEC article 210.8, GFI protection, this states the necessity for ground fault protection almost everywhere in a house and especially garage, and out buildings, anywhere ungrounded tools may be used. Same problem, handle tie required on two pole c/b.
3. Article 210.12 Arc-fault protection, this states all 15 and 20 amp circuits in a home to have either arc fault or combination GFI/AFCI breaker protection. There are no currently manufactured breakers being made that can do this for a multi-wire branch circuit as they all break at the supply the neutral, which isn’t possible with a three wire branch circuit, you’d have to use a two pole GFI/AFCI breaker, again loosing individual control of either proposed circuit. These excerpts were taken from the 2014 edition of the NEC and these same sections may be “googled” for anyone to reference. We can dispute the nuances in a pm if you desire. Dan
 
Sparky75

Sparky75

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I will look tonight and tomorrow at the exact specifications and distances and post them. We have had her off the THC oil because I cannot afford it alone without the help of the ex. She has had a relapse and now she is willing to help again. I will post the distance of the run and what box I have in the basement and see if it can be upgraded based on the wiring running to the box or if I can run another wire from the box straight down to the basement and install another box. I will try to be more detailed. Thanks for all the good information.
 
PipeCarver

PipeCarver

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So here’s three initial problems with what you’re thinking and advising others without any experience (demonstrated electrical) to do:
1. NEC article 210.4; concerns multi-wire branch circuits (three wire, shared neutral per your sketch) All ungrounded conductors must be simultaneously disconnected by means of a permanent handle tie, ie in this case two pole c/b with permanent handle tie. No individual circuit control.
2. NEC article 210.8, GFI protection, this states the necessity for ground fault protection almost everywhere in a house and especially garage, and out buildings, anywhere ungrounded tools may be used. Same problem, handle tie required on two pole c/b.
3. Article 210.12 Arc-fault protection, this states all 15 and 20 amp circuits in a home to have either arc fault or combination GFI/AFCI breaker protection. There are no currently manufactured breakers being made that can do this for a multi-wire branch circuit as they all break at the supply the neutral, which isn’t possible with a three wire branch circuit, you’d have to use a two pole GFI/AFCI breaker, again loosing individual control of either proposed circuit. These excerpts were taken from the 2014 edition of the NEC and these same sections may be “googled” for anyone to reference. We can dispute the nuances in a pm if you desire. Dan
Okay I won't dispute that its in black and white but wouldn't a ground fault receptacle solve that by putting them in the 4x4 box? Are there still groundfault receptacles even allowed anymore in your country? They're still here in Canada. One reason I'm not wiring anymore, too many new rules and that part of your code book is all new to me.

Its just that with 30 years in the electrical trade, high rise construction throughout 4+ year apprenticeship, residential wiring in British Columbia , California, Hawaii, 4+ yrs, shipyards in Hawaii & Vancouver 10 years, Maintenance electrician in a Vancouver hospital for 9+ years and independent wireman here & there inbetween I have a bit of experience in the trade and what I propose is not dangerous or unsafe and it's easy to follow. The fact there is no ground fault to me is trivial, its grounded, the entire system is grounded, to me ground fault on just about every power circuit in the house is over kill. If you're going to get it inspected then by all means pay an electrician & pay for a permit to do the work. If not why bother?
We have 1 ground fault receptacle in our bathroom and not even1 GF fuse in our 100amp fuse panel lol built before the ground fault paranoia took over.
 
Dan789

Dan789

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@PipeCarver, like I tried to intimate, you, I and others have varying degrees of understanding in Electrical theory and it’s application. That said, anyone who’s viewing this thread may come off with an incorrect assumption based on what is presented. If you clearly state what the National Electrical Code (NEC) say’s, there shouldn’t be much to dispute. Many home growers and other rely on the defacto experts, at HD personal who may not really have any basis for saying anything, but continue everyday to any who will listen. When on forums like this if we perpetuate those misuses and misconceptions of what the “code” says, we join the party of those spouting useless information.
In the end everyone will take the path most available only those willing to investigate the facts will end up with an installation that both serves their use and is safe at the same time.
I can only add, that every receptacle I have in my garage supplying power to my grow set up are all protected by either a panel mounted GFI, or an individual GFI, which I feed the protection to anything downstream. That has and continues to provide protection that because of adhering to the NEC, we don’t see many situations where homes burn down because of electrical caused fires.
 

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