220 volt advice needed

[mexilandrace]

I am planning out before I buy the stuff to do this.

I could run a 50 amp 220 plug like for a dryer to a light relay and then run the lights from that? This I am sure I can do.

I am trying to save some money though and was wondering if I can build a box or something that has the 220 outlets for power to the lights, and then the other end plugs into the 50 amp dryer plug.

maximum load ever would be 30 amps.

 

[deepforest]

intermatic little grey box

cheap and easy


ps side question for an electrician that might stumble upon thread:

is it safe to run 6 1ks @ 240v on a 30 amp dryer plugin w/ intermatic timer?

guys at grow shop say it is, but i thought u were only supposed to pull 80%? i know digital timers let you pull 100% due to their design but i was surprisd that they said 6 lights on a 30amp is safe?? are they wrong

 

[mexilandrace]

I wouldn't do more than 4

 

[madpenguin]

is it safe to run 6 1ks @ 240v on a 30 amp dryer plugin w/ intermatic timer?

guys at grow shop say it is, but i thought u were only supposed to pull 80%? i know digital timers let you pull 100% due to their design but i was surprised that they said 6 lights on a 30amp is safe?? are they wrong

Yes, they are wrong. They are usually wrong about most everything. You could just squeeze by with 5 lights but certainly not 6. Not unless you want some extremely hot wire. Even then you would run the risk of tripping the breaker. Which would be infinitely better than burning your house down.

 

[madpenguin]

I am planning out before I buy the stuff to do this.

I could run a 50 amp 220 plug like for a dryer to a light relay and then run the lights from that? This I am sure I can do.

I am trying to save some money though and was wondering if I can build a box or something that has the 220 outlets for power to the lights, and then the other end plugs into the 50 amp dryer plug.

maximum load ever would be 30 amps.

Dryer receptacles are 30A. I'll throw together a parts list and tutorial if you list all your equipment and what voltage it runs at.

 

[madpenguin]

Yes, they are wrong. They are usually wrong about most everything. You could just squeeze by with 5 lights but certainly not 6. Not unless you want some extremely hot wire. Even then you would run the risk of tripping the breaker. Which would be infinitely better than burning your house down.

Let me clarify real quick. If each ballast only drew 4A, then yes, you could just barely squeeze 6 of them on a 30A circuit. I've never seen a 1kw 240v ballast that doesn't atleast draw 4.2A. That puts you at 25.2A... If you want to ignore the 1.2A overage then that's your business, but the "80%" rule is there for a reason.

Extensive tests have been done in labs with peoples sole purpose is to try and blow stuff up and catch things on fire (what a cool job that would be). It was determined after MUCH, MUCH, MUCH testing that NM-B romex can only safely sustain 80% of it's rated load for extended periods of time.

That 1.2A could mean all the difference in the world after a year of running (it could ruin the interior conductor insulation from excessive heat).

If the "experts" at the grow shop didn't look at the nameplate ratings of your ballast, do some math, and then take into account derating to 80%, then they are most certainly wrong.

 

[Shcrews]

I love the Intermatic Little Grey Box.... most useful piece of grow equipment ever (no wait, that's the AC)

I had one die on me, and i rewired another one no problem, with very little electrical experience.

to save money on ballast cords, hook it up to normal 120v plugs like i did, just make sure nobody plugs in a fan or something LOL

 

[sparkjumper]

Thats the exact setup I use for 3 1K verts,the thing that makes it different from other 240V mechanical timers is the surface on-off lever.Thats what distinguishes it from the other 240V mechanical timers.

 

[mexilandrace]

Dryer receptacles are 30A. I'll throw together a parts list and tutorial if you list all your equipment and what voltage it runs at.

well realistically I meant a 3 pronged range plug.

I found 60 amp receptacles and plugs.

I am thinking of wiring up a 60 amp 220 breaker so I can have room to expand in the future.

is there an advantage to running 2 30 amps vs a single 60? will cost more to run the dual 30s.

 

[mexilandrace]

I love the Intermatic Little Grey Box.... most useful piece of grow equipment ever (no wait, that's the AC)

I had one die on me, and i rewired another one no problem, with very little electrical experience.

to save money on ballast cords, hook it up to normal 120v plugs like i did, just make sure nobody plugs in a fan or something LOL

you just helped me out a ton, I wasn't even thinking about putting a box I was just going to hardwire into the intermatic.

thanks a ton

 

[madpenguin]

You should really read the last few pages of the sticky up top. We've covered this one 60A run kind of setup before. Sounds like you might have already if your looking at 60A receptacles and plugs.

If your not going to run #6 AWG everywhere along with the 60A receptacles and plugs, then you need to alter your setup. That WH40 is only rated for 40A as well. Sit down and think about this or your going to have a problem on your hands.

 

[mexilandrace]

and you mean the plugs for the lights need to be 6 or just the physical wiring?

and I think I remember that the reason I talked myself out of the 60 amp before was the wire required.

8 gauge is I think the limit I am going to do, so that is 40.

sorry too early no coffee in the house.

I was an electrician's wire running bitch for a couple years, I am familiar with electrical work, just don't do it much anymore.

 

[madpenguin]

Yea, #8 on a 40A DP would be better for that setup if your going with a WH40.

Technically, your supposed to run #8 everywhere and use 40A rated receptacles but that would mean increased costs as well as snipping the factory plugs off your ballasts. Most people won't do that. I would at least run #10 out of the WH40 to spec grade industrial 20A receptacles..... But that choice is ultimately up to you.