Growroom Electricity and Wiring

[madpenguin]

Thank you!
Really, it's an amazingly great thing that you're on here, giving advice like this. I can imagine it's not exactly fun answering questions all the time but then again, I do enjoy answering forum questions I have the knowledge to answer.

I now have a question about supplying power to everything.
You'd said not to hook the two lines that would be going to the in wall timer into any sort of power strip. I understand that too much current draw on a power strip can be dangerous. I'm totally ok with just plugging the mag ballast into a wall socket but that leads me to ask, what's the difference if the draw on the power strip is under 1440w? The power strip would have a circuit breaker and surge protection whereas otherwise there would only be a circuit breaker at the panel. If there's only one circuit in the room then it seems like it would kinda defeat the purpose of plugging the ballast into a wall plug, even if it's a different plug than everything else is on.

Heh. Well, so what do you suggest for supplying 8+ outlets in this cab? It'll have five separate compartments with one specifically for a fan and another for tool/nute storage. I'm figuring on using a power strip simply because it's far less expensive and possibly safer than using a 5 gang box and wiring in receptacles and 15a breaker myself. Not that I don't trust myself but I've never done that much 120v before.
Overall, I'm attempting to keep cabinet's amp draw around 10-12 so that I don't overload any circuit new or old.

Thanks again MP. You're invaluable around here.

The powerstrip is prone to failure because of the cheap contacts inside it. They like to melt if they see more than a few amps.

I would do the quad gang box with 20A receptacles any day over using a powerstrip. Theres no way a powerstrip will ever be safer than directly hardwiring receptacles in a gang box.

 

[wolfeman]

Yea, if it's this your talking about then you'll be OK.

What I have got is a little different, I've attached a pic. The one (or two) I'm referring to are in the right column, second and third down with the white thingy that keeps them in tandem.

Thanks for looking and setting my mind at ease....

 

[Orygun]

Hey Madpenguin Thanks for all the advice on my panel Issues without GS and your advice I Wouldn't have ever known how bad my panel really was.

I'll definitely let you know when I'm going to pull my meter and switch out the services, it won't be for around a month though since I have to finish my current run before I can.

One quick question about the grounding which I don't completely understand is tying the water main into the panel and why this has to be done and how you go about doing this. I'm sure it has to be done because you said it has to be but I was just wondering.

Thanks again.

 

[averagejoe]

hi ! i have a 100w hps ballast and starter, but the bulb is 150w hps... it is shining and all is nice but may this cause problems in future? also i think 100w bulb was a bit brighter.

thanks for looking at my problem,

joe

(sorry if this is a frequently asked question, i tried searching but it gave me crap)

 

[tokinafaty420]

Forget my question MP. I tried reading the whole thread and doing searches on relays, but none of it really answered my question. However, I think I have figured it out on my own.

 

[madpenguin]

What I have got is a little different, I've attached a pic. The one (or two) I'm referring to are in the right column, second and third down with the white thingy that keeps them in tandem.

Thanks for looking and setting my mind at ease....

Whats below the Range? That won't give you 240v but 2 separate 120's instead. If those 2 hot wires share a neutral, then your really in trouble.

The one on the right is ok. It's split in between both hot buses so you will get 240v between both. Placement is key when your trying to do stuff like this. So, the one on the right is 240, the one on the left is not.

 

[madpenguin]

Hey Madpenguin Thanks for all the advice on my panel Issues without GS and your advice I Wouldn't have ever known how bad my panel really was.

I'll definitely let you know when I'm going to pull my meter and switch out the services, it won't be for around a month though since I have to finish my current run before I can.

One quick question about the grounding which I don't completely understand is tying the water main into the panel and why this has to be done and how you go about doing this. I'm sure it has to be done because you said it has to be but I was just wondering.

Thanks again.

Your incoming water main serves as your main means of grounding. You will always get a better ground/lower resistance from a metal water pipe in the ground than you will from an 8 foot ground rod. This is why the water main serves as your main grounding means and an 8 foot ground rod serves as a secondary grounding means.

You need #4 bare copper going all the way from where the water main enters the basement to your first disconnecting means. Which will either be your main panel or an outside disconnect by the meter. Then from that same neutral bar that the #4 bare is attached to, you need a #6 bare running out that attaches to an 8 foot ground rod that has been driven. An acorn clamp is what is used to connect the 2. That gives you your secondary grounding means.

 

[madpenguin]

Forget my question MP. I tried reading the whole thread and doing searches on relays, but none of it really answered my question. However, I think I have figured it out on my own.

Relays are just used when you have a rather large load to switch and you don't want to risk using a cheap timer to do it. In that case, you use the cheap timer to trigger the contacts of the coil on the relay.

You really only want to use a relay when you have too much power to switch and a regular timer won't handle the load.

 

[diamondmine]

Yo Mad- I have an inline duct fan it's 110V, is it safe and proper to just stick a plug on it and plug it into the wall? It will be running 24/7.

 

[madpenguin]

I don't see why not. What kind of a fan is it?

 

[crosseyed]

my house has 200 amps.. how many 1000w lights would i be able to run without it tripping? 10 at a time max?

 

[SmokinErb]

Dropped back in for another quick question. Cheap walmart Brinks timer. Says its rated to "15 A resistive, 500W Tungsten, 1/3 HP"

500w max load? 15 amps? Not sure if I can plug 800w of light into it safely. I've been either running 24/0 now or 18/6 on hot days, and I'm about ready to cut back the lights. I've only got 1 timer right now, and 3 lights to control. I was thinking about maybe a relay, but meh. Timers are pretty cheap. It's more of the space to plug them in at. They take up too much damn room. I've got a work box with 2 sets of receptacles in it (4 total) but they're so close together, I can't exactly plug in 3 timers to it really.

 

[SmokinErb]

And crosseyed, you'll need to tell him the voltage rating of the circuits.

Obviously you can run more power on a 240 than a 120. @ 120v, I wouldn't exceed 15,000w probably. Maybe 20,000.

 

[madpenguin]

my house has 200 amps.. how many 1000w lights would i be able to run without it tripping? 10 at a time max?

There's really no direct answer to that. You may have a 200A service but remember about your fridge, microwave, electric stove, clothes dryer, electric furnace, electric water heater, dishwasher, garbage disposal, computers, TV's, lights, curling irons, hair dryers and so forth.

And yes, the voltage that your ballasts are going to be running at is key to answering that question.

 

[madpenguin]

Dropped back in for another quick question. Cheap walmart Brinks timer. Says its rated to "15 A resistive, 500W Tungsten, 1/3 HP"

500w max load? 15 amps? Not sure if I can plug 800w of light into it safely. I've been either running 24/0 now or 18/6 on hot days, and I'm about ready to cut back the lights. I've only got 1 timer right now, and 3 lights to control. I was thinking about maybe a relay, but meh. Timers are pretty cheap. It's more of the space to plug them in at. They take up too much damn room. I've got a work box with 2 sets of receptacles in it (4 total) but they're so close together, I can't exactly plug in 3 timers to it really.

Are all 3 lights being run on the same photo period?

Is your junction box with the 2 duplex receptacles loose, as in, do you have some free cable to play with?

If both those questions are "yes", then I probably 'would' insert a relay junction box before the 2 duplex receptacles. Then just make a long trigger cord for the coil contacts that you can plug in somewhere else.

I don't think you mentioned what wattage and voltage the 3 lights run at so I don't know if it's safe to directly use one timer for them all or not. Oh.. sorry. 800w. Yes. That should be an acceptable load for your timer. But that means you have to use a powerstrip or extender of some sort because I don't think I've ever seen a cheap timer that has 3 receptacles on it.

I've been running 12A off my cheap 15A digital timer for a year now without mishap. Still makes me nervous and I probably shouldn't do it but the timer hasn't melted yet...

 

[PharmaCan]

Obviously you can run more power on a 240 than a 120.

This is a common misconception. Using 240v you can run the same amount of current using fewer wires. I'll give an example below, but I rounded the amps for clarity so don't anyone jump on me because the numbers aren't exact.

Let's say you have a 1k light running on 120v. Two wires supply power, a hot and neutral. The hot wire brings in 8.4 amps of 120v power; the neutral completes the circuit.

Just for fun, let's say we have an 11 amp circuit breaker and wire that is rated for 11 amps. At 80% we can safely draw 8.8 amps, so our circuit is now maxed out with the one 1k light.

Now we are going to convert to 240v. We disconnect the neutral, it's not needed for 240v, and hook that wire up to a new 120v breaker - i.e. we install a double pole 240v breaker, which is actually two 120v breakers hooked together. So now we have two hot wires instead of just one. Each of these hot wires has 120v and is capable of supplying a continuous load of 8.8amps,for a total of 17.6 amps.

When doing the calcs for your load you come up with:

1000watts/120v = 8.4amps

1000watts/240 = 4.2 amps

While 4.2 amps looks like it is half the power, that is 4.2 amps is per hot leg. Since there are two hot legs, 2x4.2 = 8.4, so the total amp draw is the same.

Back to our circuit, if you do the math, we can now power two 1k lights at 240v using the same wires that were good for only 1k at 120v. However, 2k in lights will draw twice the amount of electricity and cost twice as much to operate, as 1k. Bottom line is that sending the electricity through different wires isn't going to affect the amount you use.

I hope this helps someone understand the concept of 240v more clearly.

PC

 

[HerbalSmoke]

Hey MP. This would be SmokinErb here, using a buddies account. I got a one week ban for some shit, but I really need to get this cleared up. The safety of me and my roommates some > some petty internet ban.

I'm only running two lights right now. They're both 400's @ 120v. I have another light, but it's not being used right now. My timer has 2 built in plug recepticals, and the question is regarding the 2x 400w lights.

What I'm getting is that you're saying I'll be okay on using 800w in that? 15a rating tells me to go ahead and use it, but there's a 500w Tungsten right next to it that's got me nervous. Can you tell me what that 500w is for?

I'm actually going to go ahead and plug both of them into it right now and see what happens. I'm pretty sure I'm understanding you clearly, but I just wanted to make sure. And you're running 12a on a 15a timer? You're telling me I can run all 1,200w on that single timer?

 

[HerbalSmoke]

Back to our circuit, if you do the math, we can now power two 1k lights at 240v using the same wires that were good for only 1k at 120v. However, 2k in lights will draw twice the amount of electricity and cost twice as much to operate, as 1k. Bottom line is that sending the electricity through different wires isn't going to affect the amount you use.

That's pretty much what I meant. You can run more lights on a 240 circuit than a 120. Yes, you pay for the electricity, but if you're trying to get as much light in a given amount of space as possible, 240 trumps 120... because you can run twice the light.

Or am I wrong again? I'm learning here.

I'll post back under my account when my bans up in a week. Sorry if this pisses any admins/mods off or whatever. But like I said. Fire Hazard > Stupid ban (And yes, it was stupid.)

 

[madpenguin]

My timer has 2 built in plug recepticals, and the question is regarding the 2x 400w lights.

What I'm getting is that you're saying I'll be okay on using 800w in that?

Yep. Your fine plugging a 400w ballast into either receptacle for a total of 800w on that timer.

15a rating tells me to go ahead and use it, but there's a 500w Tungsten right next to it that's got me nervous. Can you tell me what that 500w is for?

Tungsten is a metal on the periodic table of elements with a high resistance. That's what the filament in incandescent bulbs are made of. Incandescents are your typical light bulb. I believe halogens also use tungsten but I'm not 100% sure. I really need to keep/brush up on my lamp technology.

Tungsten also temporarily draws quite a bit more power at startup until the filament heats up enough to start glowing. This is why the tungsten rating will always be less than the resistive rating (a motor load does the same thing, see HP below).

A purely resistive load would be a baseboard heater or hot water heater.

The Horse Power (HP) rating is for motor loads. 1 HP=746 watts if I remember correctly but please don't quote me on that. 99% sure.

I'm actually going to go ahead and plug both of them into it right now and see what happens. I'm pretty sure I'm understanding you clearly, but I just wanted to make sure. And you're running 12a on a 15a timer? You're telling me I can run all 1,200w on that single timer?

Yes, you can but I really don't recommend it. I'm being a hypocrite because I have a 600w ballast plugged into either receptacle on my timer for a total of (roughly) 1200w @ 120v.

When using HID or Florescent lighting go ahead and use the resistive rating. For fans, use the HP rating and for regular light bulbs use the tungsten rating.

Just always remember the continuous load ( 3 hours or more) deal and stick to it. If the timer is rated for 15A then derate it to 80% for continuous loads and you get 12A.

See, if you use all 1200w like you want, then you have 3 or more plugs but only 2 receptacles. That means your going to be using an extension of some sort to get everything plugged in and that's where your going to run into trouble.

Avoid those things whenever possible. Things like powerstrips, extension cords and extension receptacles. Even if they claim to be "Heavy Duty" Do Not Put Your Faith In Them. It just creates one more connection point which means one more point that your likely to get a weak connection which means resistance gets out of hand which means heat builds up which means something is going to melt or catch on fire.

Ever seen "A Christmas Story" where the Dad has about 20 extensions stacked onto one another and he's using about 30 plugs on one receptacle? Scary shit. I actually see this quite often because I do work for several property owners. I see this in apartments all the time. People just don't use common sense sometimes and I wish they would outlaw those devices...

 

[PharmaCan]

Back to our circuit, if you do the math, we can now power two 1k lights at 240v using the same wires that were good for only 1k at 120v. However, 2k in lights will draw twice the amount of electricity and cost twice as much to operate, as 1k. Bottom line is that sending the electricity through different wires isn't going to affect the amount you use.

That's pretty much what I meant. You can run more lights on a 240 circuit than a 120. Yes, you pay for the electricity, but if you're trying to get as much light in a given amount of space as possible, 240 trumps 120... because you can run twice the light.

Or am I wrong again? I'm learning here.

I'll post back under my account when my bans up in a week. Sorry if this pisses any admins/mods off or whatever. But like I said. Fire Hazard > Stupid ban (And yes, it was stupid.)

"a friend's account" lol

Yeah, it sounds like you have the right idea!

PC