Experienced Electrician! Here to Answer Any and All Growroom Electrical Questions

[ScoobyDoobyDoo]

Joe isn't that for 12 volt systems as ina vehicle? I know that isn't correct for a home.

My 200 amp box as a 30 amp dual breaker with 6awg wire coming from it out to my shed. I'm replacing the screw in fuse box in my shop with a 100 amp square D. Shop is around 40 ft away so maybe 50 ft length of 6awg wire.
With a 100 amp box in the shed it will kick the breaker in the house first.

I was playing with this link and it says I could put a 100 amp breaker on a 6awg wire out to 50 foot.
http://www.csgnetwork.com/wiresizecalc.html


Alo a couple of pages back they were talking about controllers I guess like a Titan? Anyways I was looking at those and they have small 10 amp or 15 amp pull on em and only take group of connectors like all of em was on 110 or 220. I'd like to have one that has both so I could plug all my lights fans and anything else I want on my timer. Of course it would have to be both 110 and 220 in the same unit. Anybody manufacturer a product like that? I saw a link the other day where you can build your own controller that would operate off 220. I'll see if I can find it.

#6 will be fine. remember you are pulling 2 legs of it so it's rated load of 65amps doubles to 130amps. no need to replace the wiring since it's already there.

i use powerbox controllers. i have on erased for 60amps and another rated for 40amps; at 220v. they are the best in my opinion; but pretty expensive. i've never built a light controller before but plenty of guys on here have. just make sure you buy quality contactors and relays. and test the unit with something before you go plugging all your equipment into it.

 

[ScoobyDoobyDoo]

These are the gauge sizes and ampacity of 3 conductor under 2000 volts.
14 gauge will hold 20 amps.
12 AWG.25 AMPS
10 AWG 30 TO 40 amps depending on type of cable.
8 awg 40 to 50 amps
6 awg 55 to 75 amps.
4 awg 70 to 95
2 awg 95 to 130 amps
1 awg 110 to 150 amps
the 200 amp wire range would be 4/0range from 195 amps to 260 amps.
This info is obtained from the NEC.national electrical code conductors for general wiring.1999 addition. page 70-126.
The amps depend on the class of wire used,The lowest amp rating is in TW UF rated wire,Romex as we call it sometimes.
I am a certified master electrician.But i do not work in high voltage.Im a control electrician and senior mechanic.
I do not play with power outside of a building.I leave that for linemen.
Anything within a building or structure i can make it walk and talk and do whatever you want.

when it comes to building wire it's not dependent on the wire but in the ambient temperature surrounding the wire. that's why direct burial cables (urd) are always rated a little higher. just type "wire ampacity chart" into google and you'll see a bunch come up. the difference is no where near that much. about 5-10 amps depending on the temperature. i always just use the middle column. they also have aluminum capacities on the right usually.

just remember that most anything over 30 amps is usually 220v so you have 2 legs. so loading a 200amp box with 4/0 is not necessary at all and is probably a waste of money. #2 would be fine.

 

[max420thc]

According to the national electrical code i wouldnt use 2 awg wire for 200 amps.I understand the heat has to do with the capacity of how many amps the wire will hold along with the insulation of the wire.
2 awg wire,,according to the code would not be safe.You can do what you want im sure..but burning up your grow because you saved a couple of bucks on wire would really suck.
Im just siting code from NEC.I just dont go outside of that code.For allot of obvious reasons.
Im not telling anyone they are stupid.So please dont take this wrong.If I were to go outside this code..and someones shit burned up..guess who gets in huge trouble? ME.
I have yet to burn or blow someones property up going by code.

 

[max420thc]

#6 will be fine. remember you are pulling 2 legs of it so it's rated load of 65amps doubles to 130amps. no need to replace the wiring since it's already there.

i use powerbox controllers. i have on erased for 60amps and another rated for 40amps; at 220v. they are the best in my opinion; but pretty expensive. i've never built a light controller before but plenty of guys on here have. just make sure you buy quality contactors and relays. and test the unit with something before you go plugging all your equipment into it.

A rated load of 65 amps is a rated load of 65 amps.Makes no difference if it is 120 volts or 220 volts.
220 volts will pull half the amps of 110 volts..It will not however double the amps That a conductor will hold.
1000 watts of power from 110 volt and 1000 watts of power from 220 is still 1000 watts of power consumption.The only difference is the 220 volt will draw only half of the amps.
Example a 30 amp breaker will hold three 1000 watt bulbs at 10 amps..but will hold 6 of them at 5 amps each.In theory.
I never max out a circuit to the extent of its breaker or wire.I try to keep it at no more than 75% of its rated amp rating.

 

[ScoobyDoobyDoo]

According to the national electrical code i wouldnt use 2 awg wire for 200 amps.I understand the heat has to do with the capacity of how many amps the wire will hold along with the insulation of the wire.
2 awg wire,,according to the code would not be safe.You can do what you want im sure..but burning up your grow because you saved a couple of bucks on wire would really suck.
Im just siting code from NEC.I just dont go outside of that code.For allot of obvious reasons.
Im not telling anyone they are stupid.So please dont take this wrong.If I were to go outside this code..and someones shit burned up..guess who gets in huge trouble? ME.
I have yet to burn or blow someones property up going by code.

i don't go outside wiring code either; but i think you may be looking at the chart incorrectly. with a distance of 50' then #2 will be just fine. there will be little to no voltage drop and #2 wire is rated for 115 amps. i use thhn for building wire and aluminum urd for service cables. i am pretty experienced with electricity and do almost all of my electrical installations for both my grow rooms and the homes we build. trust me...my grow rooms are not burning down because of anything electrical.

new project i'm working on...




160' run of 2/0 aluminum urd service cable to a dedicated 150amp panel


all new wiring, breakers, boxes, receptacles, etc..


construction

 

[Sand4x105]

A rated load of 65 amps is a rated load of 65 amps.Makes no difference if it is 120 volts or 220 volts.
220 volts will pull half the amps of 110 volts..It will not however double the amps
bla-
bla
bla.

While technically you are correct, basically you are wrong...
And Scoobie while technically wrong, is correct....

If you have a 220 20 amp light it will pull at 220 vac 10 amps per leg [two legs of 110 on 220]
If you have a 110 vac light at 20 amps it will pull 20 amps per leg
So two lights on 110 VAC is 20 amps per leg
So two lights on 220 vac is 20 amps per leg
Ohms law does not change... learn it...

Now being safe is the best way...
Wasting wire, and adding cost to a grow room is also stupid....
Be safe, don't go over board...

 

[ScoobyDoobyDoo]

A rated load of 65 amps is a rated load of 65 amps.Makes no difference if it is 120 volts or 220 volts.
220 volts will pull half the amps of 110 volts..It will not however double the amps That a conductor will hold.
1000 watts of power from 110 volt and 1000 watts of power from 220 is still 1000 watts of power consumption.The only difference is the 220 volt will draw only half of the amps.
Example a 30 amp breaker will hold three 1000 watt bulbs at 10 amps..but will hold 6 of them at 5 amps each.In theory.
I never max out a circuit to the extent of its breaker or wire.I try to keep it at no more than 75% of its rated amp rating.

i don't think you understand what i am trying to explain. i'm fully aware of what a rated load is. i think you are getting confused. i think the table # in the NEC book is 310-16. is that the one you are looking at?

 

[max420thc]

EIO?20 amps is 20 amps...Learn it.
If you take your amp meter..and put it on one leg of a wire going to 220..you are going to read 5 amps..aprox. Running 1000 watts.If you put your amp meter on a 1000 watt 110 volt you will read 10 amps.You will read this on either the L1 side.or the common wire.correct?Same with 220..either leg you will read half the amp draw of the 110 right?How does this change the fact that The wire will only hold and is rated for a given amp draw?Just because you run 220 to it does not increase the amount of amps the wire will hold.According to code.
You think just because you ran 220 volts through a cable you can double the rate of the amount of amps the cable will hold? HELL NO.You can double the amount of watts though that can be run through the wire.
I used the general wiring section of the code for reference.
Ive got a pile of work to do.But on page 70-125 under residential wiring.Table 310-15(b)(6)
3 wire in single phase dwelling service.
It has number 4 copper and no 2 alum holding 100 amp feeder service rating.
With 2/0 copper and 4/0 alum holding 200 amps.I stand corrected.
I dont think i was looking at the code wrong.Just a different code from residential.I was looking at the general code.
Its been a long time since ive cracked the NEC..it had dust all over it.

 

[Stevie51]

a useful tool I found. http://www.csgnetwork.com/wiresizecalc.html

That link you posted is more worthless than a box of rocks. You should use NEC Table 310.16 or the newer 2011 edition NEC Table 310.15(B)(16). If you are a DIY, I suggest that you should stick to using the 60 degree Celsius column, unless advised by a License Electrician to use the 75 degree Celsius column. Do not use the 90 degree Celsius column, unless you are using that column for derating calculations. I am not a License Electrician but I did stayed at a Holiday Inn Express last night. The NEC Tables does not take into consideration voltage drop, so you will need to use a voltage drop calculator to determine if your final voltage is within the recommended voltage drop, however I feel that will not be necessary for length of 50 feet and under.

 

[ScoobyDoobyDoo]

EIO?20 amps is 20 amps...Learn it.
If you take your amp meter..and put it on one leg of a wire going to 220..you are going to read 5 amps..aprox. Running 1000 watts.If you put your amp meter on a 1000 watt 110 volt you will read 10 amps.You will read this on either the L1 side.or the common wire.correct?Same with 220..either leg you will read half the amp draw of the 110 right?How does this change the fact that The wire will only hold and is rated for a given amp draw?Just because you run 220 to it does not increase the amount of amps the wire will hold.According to code.
You think just because you ran 220 volts through a cable you can double the rate of the amount of amps the cable will hold? HELL NO.You can double the amount of watts though that can be run through the wire.
I used the general wiring section of the code for reference.
Ive got a pile of work to do.But on page 70-125 under residential wiring.Table 310-15(b)(6)
3 wire in single phase dwelling service.
It has number 4 copper and no 2 alum holding 100 amp feeder service rating.
With 2/0 copper and 4/0 alum holding 200 amps.I stand corrected.
I dont think i was looking at the code wrong.Just a different code from residential.I was looking at the general code.
Its been a long time since ive cracked the NEC..it had dust all over it.

i've been doing this for 10 years and we wire up commercial UPS systems through transfer bypass switches to 40kW water cooled generators. we do all of own service connections and residential wiring. if anything...i wire above code almost all of the time. in my houses, grow rooms, and spec homes i use #10 wire on 30amp breakers to 20amp outlets in every room. i don't need a lesson on residential electricity cause i do it every day.

you don't understand the principal of 2 legs; which is the point of the discrepancy between our views. you are confusing current and draw. 2 legs means 2 times the draw on that circuit. just at a slower current.

 

[Greenthumbskunk]

Wouldn't how many watts you can carry and also amperage have to do with the length of the run of wire?

Pretty sure 14/3 couldn't carry a 15 amp load over 2 miles away. The shorter the wire the more it can carry. Just look at buse fuses, see the amp rating of em and look how small that wire is.
Here at work everything is run off of 480 in the main plant and it's more in our new addition. Some of the wire carrying these amounts of current short distances is not very big at all. We have some cable run supplying power to presses that are as big as 3" thick. It's funny how current works and it's an art to understand it.

 

[ScoobyDoobyDoo]

Wouldn't how many watts you can carry and also amperage have to do with the length of the run of wire?

Pretty sure 14/3 couldn't carry a 15 amp load over 2 miles away. The shorter the wire the more it can carry. Just look at buse fuses, see the amp rating of em and look how small that wire is.
Here at work everything is run off of 480 in the main plant and it's more in our new addition. Some of the wire carrying these amounts of current short distances is not very big at all. We have some cable run supplying power to presses that are as big as 3" thick. It's funny how current works and it's an art to understand it.

you get voltage drop on longer distances. won't affect you on anything under 50' though. it's not a difference of how much you can carry...it's how much you will lose. really it's for service drops from someone's meter on the road back to a house way back on a property. nothing within a residential unit will pertain to this.

 

[max420thc]

You got one leg..l1 that holds 120 volts..the force of electricity.Then you have a second leg..sometimes called L2 this also has another 120 volts.Now we are hitting the appliance with 240 volts..or twice the force that we hit 120 on.In theory you are hitting the head of the nail with a hammer that weights two pounds in stead of one pound.
Driving the nail easier twice as far into the wood.
For the most part the size of the wire and how many amps is written right on the side of the wire..you just size it to the breaker and appliance and its done.You would have to be pulling the wire a long ways to exceed what most of us would ever see in order to consider additional wire size for length of run other than what is specified on the side of the wire.
I agree with over sizing the wire and over doing things some.
Volts=force
Amps =flow
watts=use
Ive seen men blown up and catch on fire..ive been blown across a roof and didnt even get into the power..i was about a inch away(20 ton rooftop cooling unit)..grounded good and had 440 three phase blow me down and burn the tip of my finger nail off.That was time for a break and my lucky day.Im still alive.
Some power jerk electrified a ceiling grid my buddy got into wiring up some control wire..blew all of his joints apart in his body..the only thing that saved him is another one of my work buddies kicked the ladder he was on out from under him.
All of these things happened with three phase.

 

[Sand4x105]

Dude... this is the worst analogy I have ever read....

• You got one leg..l1 that holds 120 volts..the force of electricity.Then you have a second leg..sometimes called L2 this also has another 120 volts.Now we are hitting the appliance with 240 volts..or twice the force that we hit 120 on.In theory you are hitting the head of the nail with a hammer that weights two pounds in stead of one pound.
  Driving the nail easier twice as far into the wood.​

• ​
  
  
  
  

 

[Sand4x105]

Power is what?
It does not equal voltage...or does it as you say?
Come on now... what's the answer....
Come on now this is a stoner forum...
You trying to confuse the masses?

 

[xLtdEspVx]

Basement Grow Q's
Hey guys, I'm new to the forum and just had a quick electrical question. I'm setting up my first grow room and right now I'm on a 200amp breaker box. I'm currently in a tent in my basement running a 1000w light and ballast. Now, my basement has three main circuits, minus washers dryers and the sump pump. Both are on 120V breakers. One for lights, one for receptacles, and another for a GFI unit from my satellite company, this circuit also has my outside receptacles on it, which are never used. Now the problem with the lighting circuit is all the outlets are on light switches. I was wondering if I could attach my ballast to this outlet and use the light switch to flick it on and off? Also, running only one 1000 watt how should I go about plugging it into the circuit? e.g) power strip, direct to outlet, or something else. any help would be appreciated!

 

[grapeoptimo]

This is an odd question, I have an old hydrofarm magnetic ballast 1000w HPS is what it says on it and what the stuff on the inside says, after I noticed this I stopped doing the following. I had a 400W MH plugged into it and running in my basement for a month or so, with really no issues. How is this possible? How does it work? IS it SAFE?

 

[xLtdEspVx]

This is an odd question, I have an old hydrofarm magnetic ballast 1000w HPS is what it says on it and what the stuff on the inside says, after I noticed this I stopped doing the following. I had a 400W MH plugged into it and running in my basement for a month or so, with really no issues. How is this possible? How does it work? IS it SAFE?

Yeah that's really not a good idea, First of all your running the wrong bulb on Ballast.. An HPS should be used for an HPS only.(They make cheap and reliable switchable magnetic ballasts if you're interested in that) You're other issue is its giving off WAY too much wattage for that bulb. The bulb will blow, its just a matter of time, and with that much power you do NOT want to be around the grow space when it happens. The chemicals in the bulb are real bad for you never-mind the shattering glass that could do some damage.. If I were you I would consider getting a new ballast.. look at something like this. http://www.amazon.com/Virtual-Sun-VS400WMB-400-Watt-Magnetic/dp/B005M96O5E/ref=sr_1_15?ie=UTF8&qid=1389718688&sr=8-15&keywords=400w+magnetic+ballast

Also, just for future reference, with magnetic ballasts you HAVE to use the right size bulb with the right size ballasts. Most Digital ballasts however can alternate between bulb sizes, and have dimming functions but are much more expensive.

 

[augusto1]

How many amps can be drawn from a 25 kva transformer? I am asking because I have seen three houses connected to a 25 Kva transformer and all three houses have 200 amps main breaker.

Thanks In Advance.

 

[Nookies]

So assuming my room is wired to only handle 15 amps and assuming I have a 15 amp breaker. How much would it cost to just have an electrician come in and rewire just my room to be able to handle 20 amps? It's possible to just do one room right?!

I'm still a bit paranoid/concerned with the amp drawage but im sure ima be fine. I'm sure most rookie growers here have a 400 watt/fans plugged up in a room with other electronics going :S

Definitely going to surpass the 80% rule of thumb thing and ill be cutting it close. Hopefully if it goes over it just flips my breaker and no fire occurs :S

All that said, I pulled out one of my light sockets and was unable to identify the wiring colors/gauge because the wires were inside a thick, wire one. I'm guessing to protect them :S