Experienced Electrician! Here to Answer Any and All Growroom Electrical Questions

Do you guys think I will be ok running a window unit and my light through a 100 foot 10 gauge extension cord on a 20 amp breaker? my light is a 1000 watt dimmable ballast with a 600w hps bulb and my a/c is a 8000 btu haier window unit I need to check the efficiency rating

NewGreen92 said:

Do you guys think I will be ok running a window unit and my light through a 100 foot 10 gauge extension cord on a 20 amp breaker? my light is a 1000 watt dimmable ballast with a 600w hps bulb and my a/c is a 8000 btu haier window unit I need to check the efficiency rating

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Why don't you try it and give us your feedback. I've seen people using 100 feet of 12 gauge extension cords to power a 1.5 hp pump motor to their above ground swimming pool on a 15 amp breaker, until an inspector one day happen to be driving by and notice it. Although you will be pulling a few more amps than that pool pump motor, you have an extension cord that can handle more amps and a larger breaker.

You should really look into a permanent installation to move that much power. Extension cords are ok for temporary measures, but are far from 'the right tool for the job'. It's too long, you can trip on it, it might have nicks already in the insulation and the conductor, etc etc..

Quick Question.

I have two spare 20 amp circuits on my main panel in garage. I already ran TWO 12/2 Romex cables through the attic, from garage to the room.

Would it be OK for me to take each cable and install a box with 4 standard 20 amp 120v plugs?

so when done, I would have two 4" boxes on the wall, total of 8 outlets, each box on their own 20 amp circuit.

I plan on plugging 1 1000 watt into each box, and splitting up the fans between the two.

so this will be a 2k grow, add everything else in, maybe 2500 - 2600w.

Will this be ok? I read alot about installing a sub panel in the room, then outlets off that..

Since I have already ran the two 12/2 cables through attic and have the two spare 20 amp circuits in my main panel, Im trying to avoid having to buy and re run more romex for 240v to feed a sub panel.

Would my plan still be safe?

Could I still do a sub panel box w a timer even though I have 2 12/2 wires, not the usual 1 big 8/3 or whatever feed wire?

I would properly feed a 220V sub panel and remove/save the 2 wire romex for some other project. I know it sucks to install but you'll be way happier in the end, especially if you plan on using that room for a while.

Now, you /do/ already have 4 12 gauge wires ran.. you could run a single 220V circuit with what you have. Whether or not it can safely supply the amperage is up to you to find out as it's based on distance, conduit type, number of wires in the bundle, ambient air temp, insulation type.. blah blah. But that's why they have reference books! Also, I'm not sure it's kosher to split up conductors in different conduits for 1 circuit. Seems hokey to me, but I don't see why you couldn't. I'd really prefer a single cable bundle/conduit.

BACG said:

Quick Question.

I have two spare 20 amp circuits on my main panel in garage. I already ran TWO 12/2 Romex cables through the attic, from garage to the room.

Would it be OK for me to take each cable and install a box with 4 standard 20 amp 120v plugs?

so when done, I would have two 4" boxes on the wall, total of 8 outlets, each box on their own 20 amp circuit.

I plan on plugging 1 1000 watt into each box, and splitting up the fans between the two.

so this will be a 2k grow, add everything else in, maybe 2500 - 2600w.

Will this be ok? I read alot about installing a sub panel in the room, then outlets off that..

Since I have already ran the two 12/2 cables through attic and have the two spare 20 amp circuits in my main panel, Im trying to avoid having to buy and re run more romex for 240v to feed a sub panel.

Would my plan still be safe?

Could I still do a sub panel box w a timer even though I have 2 12/2 wires, not the usual 1 big 8/3 or whatever feed wire?

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You started out with a good plan to run two 120 volts branch circuits, why all the sudden you have the urge for 240 volts? Two 1000 watts ballasts @ 240 volts will have the same sum total current (amp) draw of 10 amps through a sub-panel as would be with the ballasts placed on two 120 volts circuits as you described.

I had just read and been told having a sub panel in the room is safer.. But is my idea of having two straight boxes w outlets on the wall and plugging ballasts right to them unsafe? Maybe just use 2 manual timers? Should be plenty of spare amps on either 20 amp circuit. Ive been told NOT to plug ballasts straight to wall. Friend says i need a "box on the wall w built in timer" and i need to plug ballast into that.

BACG said:

I had just read and been told having a sub panel in the room is safer.. But is my idea of having two straight boxes w outlets on the wall and plugging ballasts right to them unsafe? Maybe just use 2 manual timers? Should be plenty of spare amps on either 20 amp circuit. Ive been told NOT to plug ballasts straight to wall. Friend says i need a "box on the wall w built in timer" and i need to plug ballast into that.

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Your original plan to run two 12/2 with ground NM-B (Romex) cables to 120 volts outlets as you described is very safe. You may even be able to plug in a 5,000 btu air conditioner (nothing larger than 5,000 btu) to one of the outlets if needed. A sub-panel is only necessary when you are running more 1000 watts ballasts in that room, so bear that in mind if you plan to expand the lighting in the future. Yes you will need two timers (one for each ballast) for now.

His total amp draw going to the room would be double on 110V, not the same.

I say anything pulling a kilowatt or more should be 220V. Less heat in the conductor.. you can use a smaller gauge wire.. The advantages are many. You can pull 110V off the panel too..

I thought 12/2 wire meant there were only 2 conductors in the bundle. If there is a 3rd for a ground fault.. yeah, that's fine if you wanna keep them 110V. I wouldn't move 2KW anywhere without an isolated fault circuit though.

In the 12/2 wire there is white black and bare (ground). Im no electrical guy by any means but did you assume there was no ground in 12/2 ?

Would it be any help to get the circuit breakers with arc fault protection? The little curly white wire coming off the breaker? Lol dont laugh i dunno wtf it means, but would that add safety?

You don't need arc fault... 12/2 always has a ground, same with-6/3 , 10/2 , 8/3 , 12/3 they all have a ground....Romex/MC wires and cables always have a ground if bought new... Hook all your grounds always back to and at continues to panel from equipment.... Good Luck!

I've done some research on BACG. Simple enough to do on anyone in this forum by using your computer mouse to left click on the person's name in the upper left of their post. Seem to me BACG has a 4'x8' grow tent in a spare bedroom, or at least was planning on doing one. Am I correct BACG? Based on that information, I'm going to invoke the K.I.S.S. rule and stick to my advice as already been stated in my previous posts to BACG for the present time. KISS is an acronym for "Keep it simple, stupid" as a design principle noted by the U.S. Navy in 1960. The KISS principle states that most systems work best if they are kept simple rather than made complex. BACG, or anyone else, is more than welcome to left click on my name for my advice or reply on other electrical subjects.

Stevie51 said:

I've done some research on BACG. Simple enough to do on anyone in this forum by using your computer mouse to left click on the person's name in the upper left of their post. Seem to me BACG has a 4'x8' grow tent in a spare bedroom, or at least was planning on doing one. Am I correct BACG? Based on that information, I'm going to invoke the K.I.S.S. rule and stick to my advice as already been stated in my previous posts to BACG for the present time. KISS is an acronym for "Keep it simple, stupid" as a design principle noted by the U.S. Navy in 1960. The KISS principle states that most systems work best if they are kept simple rather than made complex. BACG, or anyone else, is more than welcome to left click on my name for my advice or reply on other electrical subjects.

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Thanks stevie! Ended up going with my original plan like you said and it seems to work perfectly.

Had an electrician come check everything out today and he said everythings good. Good to hear for me!

So many people will tell you 20 different ways and im sure theyre all great, but yeah im gonna start telling them "KISS PRINCIPLE, DUDE" hahaha.

Hi, here is a schematic for a solenoid water valve controlled by a soil moisture sensor for outdoors use.

What control electronics would be necessary to switch the solenoid valve for 2 minutes when the humidity sensor hits a certain level? What kind of battery would be suitable?

mate im having trouble wiring up a bathroom fan ive got a fuse switch that has power when I plug in in to the wall but ive no idea how to wire the fan to it ive tried a 3 core wire n I just tried a 4 core wire please help

shax said:

mate im having trouble wiring up a bathroom fan ive got a fuse switch that has power when I plug in in to the wall but ive no idea how to wire the fan to it ive tried a 3 core wire n I just tried a 4 core wire please help

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Be more specific and I will lay out a connection schematic. Describe this "fuse switch". What is the voltage of the fan? What is the supply voltage?

tuone said:

Hi, here is a schematic for a solenoid water valve controlled by a soil moisture sensor for outdoors use.

What control electronics would be necessary to switch the solenoid valve for 2 minutes when the humidity sensor hits a certain level? What kind of battery would be suitable?

View attachment 2758286

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Go to ebay and buy an Omron H3CA relay. Make sure to include an 11 pin base (if it isn't already combined). Because you are playing with such a low voltage I will suggest to buy it new, not used. It can be powered with any voltage from 12-240V (AC or DC) but if the internal contacts are old and abused by 120V DC (which may be the case if it is used) it may give the low voltage a hard time breaking through the dirty contacts (which cannot be cleaned in the case of this relay). Buy the relay and I will tell you how to wire it. P.S. Omron H3CA's can do any electrical control operation imaginable (no limit). P.P.S. Does your moisture sensor include a set of contacts which open and close a circuit when the desired moisture is achieved? If so, this is a moisture controller with integral sensor. If you want a definite answer you must be 100% specific in your posts.

contraptionated said:

Go to ebay and buy an Omron H3CA relay. Make sure to include an 11 pin base (if it isn't already combined). Because you are playing with such a low voltage I will suggest to buy it new, not used. It can be powered with any voltage from 12-240V (AC or DC) but if the internal contacts are old and abused by 120V DC (which may be the case if it is used) it may give the low voltage a hard time breaking through the dirty contacts (which cannot be cleaned in the case of this relay). Buy the relay and I will tell you how to wire it. P.S. Omron H3CA's can do any electrical control operation imaginable (no limit). P.P.S. Does your moisture sensor include a set of contacts which open and close a circuit when the desired moisture is achieved? If so, this is a moisture controller with integral sensor. If you want a definite answer you must be 100% specific in your posts.

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That's brilliant info thanks, I haven't decided which moisture sensor to buy for the moment, you can see from the choice on ebay, there are many $15 versions to choose from, i have seen some arduino adapters sold with moisture sensors that may have a kind of switch on them, i dont know, it may be better to make the control electronics at home... http://www.ebay.com/itm/Soil-Hygrometer-Detection-Module-Soil-Moisture-Sensor-/281043772532... As you say if there is a reliability/sensetivity risk, it could be good to have a redundant relay also available at a different humidity rating.

That sensor you posted a link for (the $2.53 module) operates on a very low voltage which would require another power supply if you choose to use an Omron (11 pin) H3CA. You will also need a relay which operates at the same voltage as the analog alarm (signal) output (of the moisture module) and the contacts of this relay would need to be able to withstand 12V (AC or DC) or more in order to energize the Omron H3CA.
So , in other words , you need a 3.3V-5V (the product description does not specify AC or DC but it is safe to assume that it is DC when the voltage is that low) coil relay with at least one set of SPDT (single pole double throw) contacts which can sustain 12V (AC or DC depending on the power supply you choose for the Omron H3CA). The solenoid valve can be a higher voltage if you choose to supply it from the same voltage as one of your general purpose electrical outlets.
It is also worth mentioning that if you choose to gravity feed the solenoid valve you may run into problems when (or whether or not) the water holding tank is low. If there is not enough static water pressure in "off" mode the solenoid may not stay closed. This is especially true when using any solenoid that is listed as "general purpose".
Be certain that you select a valve that is listed as a "shutoff valve". If it is a plastic "made in china " valve it is not worth anything. I had my experience with roughly 50-60 of the plastic china valves and they are total garbage. The worlds most reliable valve is an ASCO shutoff valve . Spend the extra money to avert the great flood.
The only 100% fail safe way to do any automatic watering operation is like this: 1)Buy a whirlpool washing machine siphon break.
2) Put a reliable submersible pump (such as a quiet one 4000) in the water holding tank. The siphon break needs about the same flow/psi rating as a washing machine pump to operate properly, that's why I like the Quiet One 4000 pump.
3) Put the siphon break inline with the pump (the siphon break is about the same O.D. as 3/4" pvc pipe but don't try buying adapters ahead of time, just plan the tubing run after you have all the main parts in front of you). You will position the siphon break in the same way you would position a u-bend for an aquarium siphon tube. Just make sure that if the siphon break leaks (almost no chance of that happening) it will leak into the holding tank and no harm done.
3) Remember to water in small spurts (if it takes an average of 30 seconds of "on" time to water completely, set the Omron H3CA's [you need two H3CA's to do it this way] to 10 seconds "on" and 20 minutes "off". By the time the moisture disperses evenly through the soil mass, the moisture sensor may or may not detect the desired moisture level. If it is not moist enough, the cycle will repeat after the 20 minutes of "off" time. If it is moist enough the Omron H3CA's will de-energize and watering will discontinue.

NewGreen92 said:

Do you guys think I will be ok running a window unit and my light through a 100 foot 10 gauge extension cord on a 20 amp breaker? my light is a 1000 watt dimmable ballast with a 600w hps bulb and my a/c is a 8000 btu haier window unit I need to check the efficiency rating

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You will be O.K. running the 600 watt light (whether it is supplied by a " 1000 watt electronic" [aka ridiculously unreliable crap ballast] and the 8000 btu air conditioner on a 20 amp circuit (no #10 gauge wire necessary, 100 feet of #12 will not cause a significant voltage drop. If anybody says otherwise I will do the voltage drop calculation to prove it). You're ac unit will draw 6.9 amps max at 120V. You're "electronic" ballast can only draw about 9 amps max (that includes power factor losses) if it were to operate a 1000 watt bulb. You will only draw 16 amps max (continuous;the initial starting current of either appliance is not a factor in consideration of the wire size either [thats only considered when supplying a heavy duty motor, not a listed appliance such as a ballast or air conditioner] and 16 amps is the max allowed for a 20 amp circuit).
You will be drawing less amps (not more Stevie51) than a 1.5 HP pump motor (FLA of a 1.5 HP pump motor is precisely 13.4 amps at 120 volts) because you do not intend to use the 1000 watt "electronic" ballast at full power. As long as the ballast uses solid state circuitry (as opposed to a resistor bank) you will only draw about 12.4 amps with the air conditioner and 600 watt lamp operating at the same time. Unless you feel that you may upgrade this circuit to 30 amps for some odd reason, it would be a huge waste of money to use #10 awg instead of #12.
The preceding message was not a series of opinions but rather a logical chain of facts.