[Humple W.]

Hi, all. Long time lurker, first time poster (same old story). I'm building a grow cabinet for my small medical grow, and I'm now at a point where I'm stumped. I'll be running two 250w digital ballasts, each powering a MH/HPS light for each of two grow chambers. Being the noob that I am, I initially bought an Apollo 9 digital timer, only to learn that I shouldn't be using it without a relay/contacter/controller of some kind.

I have searched high, low, far, and wide for some basic tutorial on putting together a simple relay, soley for the purpose of triggering a ballast (or ballasts, since I have two). I've seen write-ups on DIY controllers and flip-flop boxes, but I think that's more than I need? Wouldn't a flip-flop only be needed if I wanted to run multiple lamps off a single ballast? I won't be doing that. I want each chamber to run independently.

So yeah, I've searched "relay" here at ICMag, and I must have read every thread that popped up in the search results, but no luck (it's entirely possible that it's there and I missed it, but I've been looking through the site for DAYS to no avail). I've googled the shit out of this, guys. Maybe I'm getting results that would be useful to someone better versed in this sort of thing, but to my uneducated eyes it all might as well be written in another language.

In summary: I want to build a simple relay (or relays if I need one for each ballast) that will trigger my light timers, without any bells and whistles. Just on and off, according to schedule. Can anyone point me to a tutorial?

And then there's the question of whether I should even attempt this at all. I know it's very foolish to mess with electrical if you don't know what you're doing. But I'm not sure if building a relay and hooking it up carries the same dangers as wiring an outlet or some such? I don't want to be nominated for a Darwin award.

Sorry for my ignorant questions, and thanks for any guidance you can provide!

[rykus]

You want an on off contactor... 120v controlled.. probably 20amp be fine ..

Basically power goes from plug into contactor control wire goes from contactor to timer to control the powers ability to go through contactor to you plug outlet receptacle (use ceramic)

Safe simple and easy... use a bigger contactor if you want to expand later.. 20amp is only good for 1 light on each side of a split 240... less if you use a 120 power source...

Cheers n hope that helps. Feel free to pm me or as I always recommend ask Rives!

[Treetroit City]

https://www.hydroponics.net/learn/gr...controller.php

That is a pretty simple relay box.

I also suggest asking rives, he walked me through building one.

[Humple W.]

Thanks for the quick reply! I will be using a 120v power source, yes. So in planning for the future, and to ensure that everything is well matched, would something like this be appropriate?

https://www.amazon.com/Packard-C230B.../dp/B001KGSJ74

[Humple W.]

Unfortunately, my post count is not yet high enough to PM. I'll keep that in mind for the day I hit 50. Thanks!

[OldPhart]

Originally Posted by Humple W.

Thanks for the quick reply! I will be using a 120v power source, yes. So in planning for the future, and to ensure that everything is well matched, would something like this be appropriate?

https://www.amazon.com/Packard-C230B.../dp/B001KGSJ74

I like it. I like enclosed contacts, just on general principle, so crap doesn't get into them as much or have sparks possibly flying around. I also like the large lug terminals for the line in/out. I wouldn't fool with all the spade terminals, I would actually remove the spade terminals, and just put all your wires into the lug terminal and tighten it down.

Edit, clearly you will have to use the spade terminals for your coil/trigger.

[rykus]

Yeah looks about right to me, sorry forgot was your first post...

I'll try to check back as well, but is pretty easy now and looks like some other knowlagable folk stopping in... and there are no stupid questions with electricity and safety imo! Make sure your sure, and ask even if it's a minor inclarity...

Cheers

[Humple W.]

Thanks! So should I get two and build two separate boxes so that I can control each light's schedule independently? Or is there a way to do it with a single trigger?

[Jhhnn]

Originally Posted by Humple W.

Thanks! So should I get two and build two separate boxes so that I can control each light's schedule independently?

Yes.

Or is there a way to do it with a single trigger?

Not easily. There are multi-channel timers out there but you probably don't want to fuss with them.

This is a good line of power relays rives recommends-

https://www.automationdirect.com/adc...AD-PR40_Series)

If you're switching 120v with a 120vtimer this is what you want-

https://www.automationdirect.com/adc...D-PR40-1C-120A

I like these timer modules-

https://www.amazon.com/Grasslin-Inte...VM8Z88GGV2KFX0

You can use steel boxes & extension boxes like I did. This has a sub panel for 240v & 120v but construction would be simpler for your purposes-

https://www.icmag.com/ic/picture.php...tureid=1343859

https://www.icmag.com/ic/picture.php...tureid=1343757

Switching a duplex outlet gives you the option of running a fan on the same cycle as the light, as in two stage ventilation.

[Humple W.]

Thanks again, everyone!

So would the part I linked (https://www.amazon.com/Packard-C230B.../dp/B001KGSJ74) be significantly inferior to the part at https://www.automationdirect.com/adc...-PR40-1C-120A? If only a slight improvement over the cheaper option, I'd prefer to spend less.