Electrical Question: What Can I Do With A 120v 30 Amp Circuit?

[Bulldog11]

Hello everybody, I am a c-10 in Cali but I can't figure out what to do with a 30amp 12ov receptacle in my garage. I am building a new grow room, and I have two 120v 20 amp curcuits with 12/2 already. Don't really need the extra power as I just veg indoors, but what can that curcuit be used for? Do they make lights that run off a 30 amp 120v plug? I know usually the plug is used for campers, but I am trying to get an idea of what it could be used for in a grow op. A/C maybe?

 

[Natural]

if you're not worried about your amp useage..I guess you can plug any darn thing that ya want to really.
lights and ac's are made to run off of 120 or 220..digi ballasts can be either..ac's are usually one or the other

 

[fishwhistle]

You can take off that shore power power receptacle(30a 120v) and change it to whatever you need then you have some free'd up power to play with.I think they also make dogbones that convert one type of plug to another if you cant change it,check out RV stores

 

[Myco]

If it's an independent circuit...

If I were you I would check the wire size, if it's 10/2 you can swap with a 30amp 240v breaker and run much more wattage off of that. Might have to move some stuff around in your panel to make that work, if you're comfortable doing it, and relocate the neutral wire to the breaker.

Then after the fact you could take that 30amp circuit to a 4 light 240v controller, or wire in some 240v plugs, or whatever.

Of course that'd only work for you if you have 240v or switchable ballasts...

Disclaimer, only do this if you're experienced with electrical, or have a buddy.

 

[Natural]

You can take off that shore power power receptacle(30a 120v) and change it to whatever you need then you have some free'd up power to play with.I think they also make dogbones that convert one type of plug to another if you cant change it,check out RV stores

lol..took me a sec...c-10...30 amp plug..aha!

 

[Bulldog11]

Thanks you guys.

10/2 wire can't be changed to 220v.

Anybody else?

 

[fishwhistle]

Thanks you guys.

10/2 wire can't be changed to 220v.

Anybody else?

Why cant 10/2 be used for 220V?Its good for up to 30amps right?Its the way most 220v household(dryer) circuits are run.There is no difference in 110/220v wire its all rated by carrying capacity so if you change the breaker and the plug,voila!Kinda tripping me out an electrical contractor doesnt know that.

 

[MGRox]

@fishwhistle technically you need a XX / 3 wire for 220v. 2 hots, 1 neutral and assuming both XX/2 and XX/3 are G rated; with ground of course.

@Bulldog11 you won't find any devices that are made for over 1500 watts on a 110v circuit as 1500 is the maximum now allowed for a 110v circuit. There are some old heaters (50's and 60's) that did go up to 2000 watts or so, but never seen anything 30 amp rated. I would probably prefer seeing 8 gauge in that line if it had much length to it, or was run a full capacity.

You could possibly replace your receptacle with a Main Lug 40 Amp panel if you wish. I have a link for something that may work below. That box would give you 2 circuits you could use with 15 amp breakers or whatever. I'm not sure if this is what your wanting here, but could pass an inspection this way (since you have a main breaker box also).
http://www.homedepot.com/p/GE-Power...anel-TL240SCUP/202978667?N=5yc1vZbm2wZ1z11spb

hope this helps

 

[fishwhistle]

@MGRox,For 110/220 yes you need 10/3 but for 220 only you do not,220 single phase is 2 hots and a ground period,you only need a neutral wire for 110v.His wire is already in so he may as well use it and as long as he keeps to the 80/20 rule and its not a long run hes good to go as far as wire size too imo.
What you might be thinking about is a 220V run like for an oven. The oven heating element only needs two hots and a ground(220), but the controls and clock are usually 110V so the oven needs a neutral to provide 110 from the run. And that wire would be xx-3 w/ground for example.

 

[ccWTF]

Some receptacles are designed to use 220volts and 12/2 wire. ACs are an example.
White and Black are hot, no Neutral wire. Ive never seen a 30 amp 110v breaker

 

[Natural]

Some receptacles are designed to use 220volts and 12/2 wire. ACs are an example.
White and Black are hot, no Neutral wire. Ive never seen a 30 amp 110v breaker

ya it's not typical..I haven't seen one either, but they do exist. I finally figured out his was meant to power an RV.
Code says..If you convert the 12-2 with ground to 220v from 120v, mark the white/neutral with marker or tape indicating it's hot.

 

[MGRox]

@fishwhistle ....well I did say technically :D Naw, I should've taken the time to explain things more fully; but am trying to learn not to ramble. Suppose I've ran into the 4 wire a bit more often than 3, but back in my High voltage days I always had a C/T trans or used return as a reference for phase. I always tend to err on the larger gauge size when dealing with higher power / or circuits that have high startup spikes. Heck, I ran 10 gauge direct for my 2x600's and even soldered and hardwired the ballasts into a mechanical timer xD.
If he were to stay with 10 gauge @ 110v and assuming a 30' length of cord; he'd be losing 27 watts (@ 30a) to the cord; in the form of heat. Depending on how well the insulation is where the wire runs, this could add up to some temp (though not likely to reach critical temps). Not an issue of course; I just can be anal sometimes with this stuff xD.

220v would definitely be better from a loss point of view (as long as he's not got a 4 prong A/C ready to be used)........I suppose he's got several options to choose from.

 

[BenMatlock]

Just thought I'd say: Be carefull of those rv converter adapters designed to change 120v to 220v for rv hookups. My cousin caught his house on fire overloading his neutral wire last year. The neutral wire carries the load back to the power company and when you hook up a 220v adapter to a 120v single phase circuit you are putting double the amps on your neutral. And yes you can run a 220 circuit with 10-2 electric water heaters are another good example.

 

[Bulldog11]

My main question of this thread is what can the wire be used for. I am not hooking up a stove, so changing the 10/2 wire to 220v makes no sense to me. I guess it could be done, but why? In other words, can lighting be hooked up to that circuit? How do ballast run, is there a 120v 30amp plug for some? Somebody mentioned air conditioners, but the split units I have been looking at wont accept 120v 30 amps.

 

[BenMatlock]

You could change the breaker to a 20a single pole and receptacle to 20 amp and plug in a 120v item. The 10 gauge wire is harder to bend round the screw on the recep but it will work.

 

[ccWTF]

thats what i would do. "De-Rate" it to 20amp by swapping the breaker.
All you need to know about safety: Dont touch the bars behind the breaker. If a screwdriver were to slip into that it could cause a flash that could melt your clothes to your body.
:(:(:(

 

[tattoojim]

I run 3 220v plugs on a 10/2 wire. Backed up by a 2pole 30a breaker. Been running it like that for around four years now.

 

[MGRox]

@Bulldog11 Something that maybe should be pointed out just in case your not aware (and to be clear). With electricity, we can make a simple analogy to help with understanding. Voltage is very similar to "pressure" (psi) with gasses or liquids and is considered a form of potential energy. Current (amps) on the other hand is more related to "volume", so a similar analogy with gasses or water would be CFM or GPM. In all actuality, amps are directly related to the total number of electrons that move past a given point in a given time.
The Volume (amps) that are delivered are based on the demand from the load (I.E. lights, a/c, whatever). If your load, for example, is a 60 watt bulb, then that 120v 30A line will be have only 0.54 Amps being drawn. So, it does not matter what the device is rated for, in terms of amps; provided it is less than your breaker max (technically 75% of max).

So, you can use the wire "as is" to run any device up to 30 amps, but you don't have to fully utilize it. Since there are no devices that can be rated for 30a @ 120v, you would have to split that line in order to use the full available power for that circuit. One advantage of changing to 220v would be that there ARE devices rated for 30a @ 220v and you would not have to split the line; while being able to take full advantage of available power.
Another advantage to 220v is related to power loss. The amount of power lost in a given line is based only on the volume (amps) running through that line vs its' resistance to that electrical movement (ohms). The less volume (amps) you have going through a line, the less power that will be lost to that line in the form of heat. Doubling the voltage, for a given power, will cut your amperage in half; this is why 220v can run more power (watts) with less volume (amps).

It's pretty much going to be up to what you need / want to hook up to that circuit. Do you just want / need 1500 watts or so? Then you can leave it as is and just run the device. Do you need 3000 watts but have devices rated for 110v? Then you can split your line to double 110v's with a MLO box. Do you want to run 3000w but have some HPS ballasts that can run on 220v? Then you would be more efficient to run a single 220v line vs double 110v circuits.

 

[Bulldog11]

I run 3 220v plugs on a 10/2 wire. Backed up by a 2pole 30a breaker. Been running it like that for around four years now.

What does it run? Lighting?

 

[Bulldog11]

Hey guys, I am an electrician so I understand everything you guys are trying to teach me. All I want to know is where a 120v 30 amp plug "could" be used in a grow room set up. If it's better to have 220v then why, and what devices run off that set up?