[fishheadbob]

Originally Posted by yamaha_1fan

It would be nice if we had a dedicated electrical section where anyone could post topics, but only a qualified few could respond.


The info posted here is very helpful

It would indeed be nice if we could separate the electricians advice from the 14 year olds opinions. After watching this site for a few years you can get a good idea whose advice is professional, and who is blowing smoke; I know I've seen examples of both. I still wonder if one guy ever burned his house down, he was trying hard to; what scared me was his comment about his girlfriend and child living in his grow-op with the lousy wiring job.
Another good option is to pick up a good DIY book about simple wiring, and don't get in over your head. Especially, don't get in over your head.

Originally Posted by madpenguin

Well, wouldn't that just be bad planning on your part? :smile:

Don't get mad, just pulling your chain. That's why I use Galaxy ballasts with sunlight reflectors..... As an added bonus, you can use Galaxy on 120 or 240...

Well when setting up a 30KW grow, you can only plan so much. The original plan was ballast kits which would have required hard wiring anyway but it turned out the Sunlight ballast was the best deal and it was alast minute change. I wasnt going to spend hundreds of dollars on adapters.

But I have learned alot from here and my BIL. I already had a basic understanding of electricity, and got the more advanced stuff from here.

Who said there friend got hit with 277? According to my BIL, thats not something you usually wind up regretting. Your friend is lucky.



If you dont know what you are doing, get advice or help. Theres alot of people here that can help. Take pictures, give detailed info, etc.

And to the experienced sparkies, stick around and try to answer as many questions as you can.

Just about all flourescent lighting circuits in commercial office bldgs come from 277V circuits.Its bad enough being hit by the hot but if you get in between the neutral and ground its soo much worse lol

[madpenguin]

This is kinda silly but for those of you who aren't familiar with electricity, I find everyday comparisons an easy way to explain it.

I already said this on another post but I'll say it again. You can compare electrical wires with water pipes.

Your water pressure is the same thing as voltage. The actual water volume in the pipe is the same thing as amperage. The amount of water that comes out of your faucet is the same thing as wattage. You can view a single water molecule as an electron. Just as there are millions of water molecules traveling in a water pipe, there are millions of electrons traveling in a wire.

Voltage is the electromotive force that pushes electrons down the wire. Electron flow will happen whenever there is a difference in potential between two points (Voltage)

View a light bulb in a ceiling fixture. If you have excessive voltage drop, the light bulb will barely light up, just as if you have excessive water pressure loss in a water pipe, you'll get barely a trickle coming out of your faucet.

Current (Amperage) is the flow of electrons from one atom to another (copper atoms in the case of copper wire).

Here is a copper atom:


The red and green dots in the middle is the nucleus of the atom. It's comprised of protons and neutrons. Protons are positively charged and neutrons have a neutral charge. The yellow dots are electrons and they have a negative charge. You know the phrase "opposites attract". The positive charge of the protons in the nucleus hold the negatively charged electrons in place. Generally, there are an equal amount of protons and electrons in an atom.

The reason why copper is such a good conductor is that the outer shell of the atom contains only one electron. This electron is loosely held by the nucleus of the atom. This outer electron is called a free electron or valance electron.

When you apply voltage to a wire, that electromotive force will dislodge the outer free electron and it travels to the adjoining copper atom. Kinda like a pool table, when 2 balls collide. The free electron hits it's neighbor free electron and knocks it out of place, but at the same time, takes the place of the one it just hit.

So current is nothing more than electrons hopping from one atom to another. The number of electrons moving past a certain point in one seconds time is the Amperage (current intensity). When 6.24 x 10 to the 18th power of electrons move past a given point in one seconds time, you have 1 amp worth of current. That's 6,240,000,000,000,000,000 electrons in one second.

So anyway, take mikecar's earlier post with why you separate neutrals and grounds in a sub panel. Here's another silly analogy.

You can view your house as a city and all the wires in it as roads.

Say a ground fault occurs. This ground fault is a car. The neural wire is one side of a street heading one way and the hot is the other side of the street heading the other way. View the ground wire as a back alley that runs parallel with the street. You want to force this car to take the back alley and not get on the road (neutral wire). Sure.... It can take either road because they both go the same way. But the main road is already congested. So put a road block up and force the car to take the back alley. It still winds up going to the same place but yet see's no traffic while it's traveling...

If you want to take it a step further, this is what a GFCI does. By all rights, that car should have gotten on the main road and traveled with the rest of them. The GFCI instantly knows that someone tried to be sneaky and cut down the back alley so it throws up a red light on the hot wire and stops all traffic until that rouge car get's back to the main panel.

I just kinda over did that one, but whatever.... Whatever helps you understand better, then look at it like that. :wink:

[nephilthim]

yea my friend got zapped with 277 he was a licensed electrician, I believe their was a loose connection somewhere he touched metal ..zap..he was shook up whenI found him a few minutes afterwards,he was fine no physical damage..mental..yea that scared the shit out of him as he was nearing retirement age.I think we all know who is licensed here so I defer to their knowledge,as all others should.

[nephilthim]

this thread gets a bump back up as so many posts are germane to posts here.

[madpenguin]

Many times when you set up a grow room, the room is already there. Drywalled, painted and finished. In that case, you can't use new work boxes with the nails, you have to use old work boxes. They are also called remodel boxes.

Old work boxes are designed to be installed into existing drywall.


They have 2 tabs on them instead of nails:


Once the box is inserted into a cut hole in the drywall, you use the screws attached to the tabs to pull the box tight to the drywall.


Here is a pic from the back side of the wall so you can see how it's held in place:



If you have access to the back side of the wall, as the above pic demonstrates, then using an old work box isn't the way to go. Especially if your cutting your hole right next to a 2x4 stud. You should probably use a new work box in that instance. Just nail the new work box from the back side of the wall. The nails will almost touch the back side of the drywall, but you can still "slide" your hammer along the back side of the drywall to nail it down.

A box nailed to a stud will always be more sturdy than an old work box positioned in the middle of 2 studs.

First, make sure you are able to fish wire into that stud location before you cut your hole. If you think it's going to be impossible to get wire into that cavity, then choose another location before you cut your hole.

Once you've decided upon a location for your receptacle or light switch, cut your hole for the box. Take the front face of the box and lay it flush with the drywall. Make sure it's level and plumb. Take a pencil and outline the box.

Look at this pic again:


There are 4 "tabs" that are a fixed part of the box. The guys thumb is on one of them. Don't trace around these when you make your outline. Those are what holds the box to the front of the drywall and the adjustable tabs get pulled tight to the back of the drywall.

You need a keyhole saw:


Cut out the hole you just outlined. There's not really a need to drill holes in the corners to get started. Just bang on the handle of your saw with lineman's pliers. It'll punch thru.

Once you have your hole, and you've made sure the box fits good:


Fish your cable. This can often be an exercise in patience as well as ingenuity. You'll figure it out one way or another.

Once you see your cable in the stud cavity, your home free. Pull it out.


Strip the end of it's outer sheathing and pull it into your old work box, just like you would a new work box, as covered on the previous post. Then put the box in the wall:


And tighten down the 2 screws:


Pretty easy, all in all, but it is time consuming and often frustrating. This is why electricians charge big bucks to old work stuff. It's much nicer when you can see studs.

If your working in an old house that has plaster and lathing strips, it get's even more frustrating. Best to use a utility knife and score your outline first. You'll be very lucky if you are left with a perfect hole that your receptacle plate covers up everything. Be prepared to do some minor drywall repair and touch-up painting when working with plaster. The stuff loves to crumble, not cut.

Also be very careful with the lathing strips when cutting. You can pull down an entire section of plaster if your saw grabs a hold of the lathing strip. You can also blow out a giant hole on the opposite side of the wall your working at if your keyhole saw goes in too deep and hit's the opposite sides lathing strips. Just take your time when working with plaster.

Here is an old work box designed for a ceiling light fixture:


Same deal with installing those.

It helps to have a basic understanding on how houses are constructed when your old working cable. Otherwise, your going to have a rough time. Often times, you can't get a clear shot from the basement panel up to the second floor. Your best bet is to locate the bathroom plumbing and use a drop chain to fish your wire.

If that's not even remotely where you need to be, then often times, pulling baseboard and punching a hole is about the only way to get from the second floor down to the first. Once you put your baseboard back on, the hole will be covered up. Use this hole behind the baseboard to drill down into the 2x4 plate. This will give you access into the first floor stud cavity**. Then go into the basement (hopefully you have an exposed ceiling in the basement) and drill up through the first floor plate to get into that same stud cavity.

Make sure you don't drill up through your floor, missing the wall cavity. That would really suck. Make sure your where you need to be before you drill.

** = Sometimes. Other times you will need to drill through 2 plates with almost a foot of dead space in between in order to get into the 1st floor stud cavity. In this instance, consider going to the first floor and punching a small hole in the wall by the ceiling. Destruction is sometimes the name of the game when doing shit like this. Do what you deem necessary to get the job done. Drywall repair sucks ass, but sometimes it can't be avoided.

[nephilthim]

i have to bump my two fav threads too much info too let this one die thanks too all you electricians who put in the hard work of data entry.perma_bump.

[madpenguin]

Haven't really mentioned this yet but it's good to know. The 2008 code introduced some pretty strict requirements for branch circuit protection (above and beyond Over Current Protection).

GFCI requirements:


AFCI requirements:


Whether or not you choose to adhere to them is another matter. I would strongly suggest that you do.

Also, tamper proof receptacles are now a requirement as well...

406.11 Tamper-Resistant Receptacles in Dwelling Units. In all areas specified in 210.52, all 125-volt, 15 and 20 ampere receptacles shall be listed tamper-resistant receptacles.

210.52 is pretty large but it basically covers all dwelling unit receptacles.

[billy_big_bud!]

lots of helpful knowledge!