4kw wiring help

[jcannabis91]

I'm currently building my new flower room 4kw. For my lights is it ok to put 2 20a duplex 240v recepricals on a 30a relay? Since I will only be pulling ~10a per receprical or do they need to all match the breaker.


Any help is greatly appreciated

 

[rives]

Using a higher-capacity relay is fine.

You want to size the breaker to the lightest-rated component in the circuit. If you are using 15 or 20 amp receptacles, then you need to stick with 15 or 20 amp breakers - 20a breakers are code compliant for 15a receptacles IF there is more than one of them on the circuit. You can use heavier wire than specified (commonly done for long runs where there can be voltage drop), and heavier-rated switching components.

However, it sounds like you might be planning on overloading the breaker. You are limited to 80% of the breaker rating for continuous loads, which are defined as any load over 3 hours in duration. For a 20a breaker, this limits you to 16a for the lighting - short term loads (pumps, etc) can bump up to the full breaker rating.

 

[jcannabis91]

I'm basically trying to build one of the 30a light controllers but can only find 15a and 20a duplex recepricals

I'm trying to build one of those putting it on a 30a breaker but my problem is I could only find 20a duplexes none that are 30a. Basically whT I was asking was if I could just use the two 20a duplex on the 30a breaker with a relay

 

[jcannabis91]

https://www.hydroponics.net/learn/grow-light-controller.asp

Was looking to do something along those lines but was wondering if I could use 2 20a duplexes instead of the 4 20a connectors

 

[rives]

No, you cannot have 20a receptacles fed with a 30a breaker. If anything goes wrong, the full current that the breaker can supply will be fed to problem area. If the device is rated for less than the breaker, then shit can get ugly. The CAP controller is junk, not-code compliant, and they are out of business. The build-up is good, but falls apart on the protection being done properly. They make 30a receptacles and cords, but they are expensive, hard to find, and will still be sized incorrectly for your ballasts.

The best option for something similar to that device is to build up the relay enclosure with the dryer cord, but instead of feeding the receptacles from the load side of the relay, feed a small sub-panel. A small sub is only about $15-$20. You can then put lower-rated breakers in the sub (roughly $5 each) and feed your receptacles. This breaks the protection down to acceptable levels and gives you much more flexibility.

 

[rives]

Here is a link to a relay that is more heavy-duty than the one in the buildup, and cheaper.

http://www.automationdirect.com/adc...n-Style,_40A_(AD-PR40_Series)/AD-PR40-2C-120A

 

[jcannabis91]

Ok I was planning on running a 60a panel for my 4 lights and my ac 30a for the lights(using ~20a) 20a for my ac(using ~13a) then like a 10a extra for little things I already have the existing electric in the room which I was going to run all my pumps and dehumidifier fans co2 all that. But your saying I should from the 30a for the lights put another load center with two 15a and put the load center on a relay? With a trigger?

 

[rives]

Yes.

Any 15a or 20a receptacle, cordset, switch, or whatever HAS to be protected by a breaker of the same rating or less. If you run a 20a receptacle with a 30a breaker feeding it, the receptacle can melt down to save the breaker from tripping. The breaker needs to be sized to the lightest-rated component in the circuit.

If you use a dryer cord>relay>subpanel>receptacle>cordset>ballast, then you can run a heavy feed (the dryer cord), switch the lights with a battery-backed digital timer (the relay & trigger cord) and still break the circuit down to the appropriate protection levels (the subpanel).

 

[jcannabis91]

Well my ac I was going to have run when the lights were on not with a controller and use my other ac on my environment controller so do you think it'd be a good idea to just run the sub panel for the ac and lights 20a for the ac and 2 15a for the lights and put the whole 50a panel on a relay like this

http://www.ebay.com/itm/281103494355?redirect=mobile

 

[Rotel]

I'm not being mean, but seriously, hire a sparky, licensed would be the way to go.

If you must diy it, buy a plug n play system and feed it code compliant.

 

[jcannabis91]

I turned my old 2k flower room into my veg room and was building my new flower room while vegging everything out but then I hit some hiccups lost my job and just barely getting by with my bills so I'm on a very limited budget (thank god I bought my nutes before changing jobs)
But I really appreciate all your help.... Thank you

 

[jcannabis91]

I can barely afford to diy it haha and even if I could I'm not in a med state so hiring someone wouldn't be the best idea I'd probably get robbed right when I'm about to chop haha

 

[Rotel]

I can barely afford to diy it haha and even if I could I'm not in a med state so hiring someone wouldn't be the best idea I'd probably get robbed right when I'm about to chop haha

As a licensed electrician myself, I'm more concerned now than ever.

Nothing good ever started with "I can barely afford..."

I came from Missouri grew there from 89 to 2012 when I moved to Colorado. Seriously, hire a sparky to set a dryer receptacle and plug in a controller after hes gone.

 

[rives]

If you want to run the a/c only when the lights are off, you can power a second small sub from the normally closed contacts on the relay that I linked up above. One sub would be on when the relay is engaged, powering your lighting. The other sub would turn on when the lights went out, powering your a/c.

You need to be careful about creating a situation where the a/c can be "short-cycled" by turning the power off and back on again before the operating pressures of the a/c subside. It can keep the compressor from restarting and will burn up the motor.

 

[rives]

Seriously, hire a sparky to set a dryer receptacle and plug in a controller after hes gone.

I haven't seen a controller yet that met code or was listed by UL.

 

[Rotel]

I haven't seen a controller yet that met code or was listed by UL.

Obviously as 240v lighting is a commercial application by nec. Doesn't mean the controller is unsafe, many titans are etl approved for commercial use.

Sure, anyone can build a contactor bank, but doing it properly requires a little experience with code compliance.

 

[rives]

Obviously as 240v lighting is a commercial application by nec. Doesn't mean the controller is unsafe, many titans are etl approved for commercial use.

Sure, anyone can build a contactor bank, but doing it properly requires a little experience with code compliance.

I think that if you take a closer look at them, virtually all of them are built around over-current protection based on NEC 410.62 for warehouse lighting. The stipulations on the conditions where this provision applies will never be met in any situation that a grower is going to be in, and yes, they are unsafe if those stipulations aren't met. Many of them use the junk "universal" receptacles that will accept 120v or 240v cord caps.

If you know of one that is code-compliant for residential use, even at 120v, I'd love to hear about it.

 

[jcannabis91]

Rotel I appreciate the concern but when I say I can barely afford to do it myself, I'm not looking to cut corners.. I have a good grasp on how this whole thing works, but wanted to make sure that's why I started this thread. Because from my research found that everything should match up. but got confused as to how I could build one of these controllers when I can't find the receptacles that were 30a. But what your telling me to do is hire someone to do the easy part then to use a light controller which will have a 30a relay with 2 15a receptacles.... If I'm going to do that I'll buy the relay for 30 and two receptacles for ten and put em in a junction box. But I'm not going to go either route.
I'm going to go ahead and put a 30a sub panel with separate 15a breakers and have the panel on a relay or intermatic timer.

 

[jcannabis91]

https://www.hydrofarm.com/downloads/fc/4 and 8 light controller instructions 3-7-12editCW_26460.pdf


Look at the specs on the controllers they're doing exactly what you suggested I don't do for $50 only difference is they cost three times the price

 

[jcannabis91]

Rives, do you think that this relay would be good for running a 30a panel with the 2 15a for the lights?

http://www.homedepot.com/p/Square-D-30-Amp-Power-Relay-Coil-8501CO7V20/202495853