ok, the reason I am building one is that I have all the materials, (except gang boxes), which I will buy, I know that you all are trying to help me, but I need this very soon, I have read a
book about home wiring, and my brother has helped an electrician one summer, so he knows alot about them, but
I was wondering what it the safest way to split the hot and neutral. And the best way to ground this box.
Thanks to all who helped, I probably would have blown myself up by now if it wasn't for you.
Below is some things to study and sugguestions on materials that often would be used. It is recommended that you do not
build this proposed box but for education value or if you are going to do it any way, here is the concepts to look into. Not as simple as just wiring up a bunch of switches and outlets - nor even dimmers to outlets and
cord. There is some very specific rules and even a 1900 wall box is frouned upon. Often the slugs from such a box other than in a wall get knocked inward and can short to even an electrical taped live
conductor or screw. Wall boxes are not recommended to use for any
portable application.
If your brother has had sufficient instruction in this he might be qualified to supervise it, one summer however does not always mean sufficiently trained as an electrician - more trained in hanging the boxes and other rough in work. Could be and possible, kind of depends upon what he was doing and how much training he had. Still it's a good start and hopefully your brother if there is something he is not trained in will have a contact to ask. Stressing the hands on, eyes on the project.
Like Bill's solution, quick and easy, save the parts and have something really good and
UL listed for the price it's going to cost you in follow up parts. 1900 boxes, covers
etc, or if that is not expensive enough the cost of removing inventory from your
stock that will at some
point need replacement. $25.00 is a good price for what it is doing. We are talking about indicator lights to show live circuits - required,
UL listed, Overcurrent protection, rack mounted and case grounded. Much less looks nice and professional.
Again with the terminology that sends up red flags: "I was wondering what it the safest way to split the hot and
neutral. And the best way to
ground this box." Split the hot and
neutral... you might know what you mean but such words
send up red flags with me thus also the concern that most share. Terms are a part of understanding. Look back at such terms five or ten years from now and you will understand the red flags about the intended project still. If what above means how to tap the hot and
neutral conductors to supply multiple switches and outlets or something similar in terminology, if the thing is not
portable and temporary in construction, than a properly sized
wire nut would be sufficient. If
portable, a cap splice is normally preferred as
wire nuts have the nasty habit of coming loose. This or sending the
power in cables to a Millenium strip for proper distribution. All assuming that before you distribute the
power, it's
line in to over-current protection such as a
circuit breaker or
fuse as required. Otherwise what happens if of these switched circuits you pull more than the rated amperage? What wall
outlet this is plugged into won't protect against
voltage drop of the load right away - read in your
electric's
book about "sub-panels", this is for all intensive purposes what you are doing here. If more than six switches you will be best with a
circuit breaker or need to have a
switch to act as a master to kill all switches.
Ok, the
neutral must be isolated from the box (for all intensive purposes much of what you are doing is a
portable sub-panel even if using switches instead of
circuit breakers) - again the
wire nut and or millenium bar or isolated
neutral bus bar depending upon the application.
The
ground is required to go to the back of the box and be attached to it by way of
ground bus or
thru the threaded hole in the back of the
conduit box. From there if two or less things requiring grounding, you can
send a 6" grounding
wire up to the device. Otherwise as long as your boxes have box to box connectors and a secure mechanical
ground, the second grounding hole can be used in the second box with the 6"
tails. Best to use a grounding bar for all grounds but it's a question of how to and box fill. This is not some electrical box installed in a wall but still must comply with "box fill requirements."
The "box fill requirements" will be in the
book along with how to do grounding and details about this.
Gauge of
wire... don't use less than 12AWG if you can help it. Unless your over-current protection on the device is specifically 15A and cannot be changed to a higher amperage, it's a bad idea.
Cord no longer than three feet and the same
wire gauge is optimum. Type MTW conductors be it stranded
THHN/MTW or specificially type MTW as different is what is normally used. Solid core
wire for
portable appications - even if within the box is not done. Cable feeding the contraption should be 12/3 SO if at all possible but 12/3 SJ would be acceptable. If you need a longer extension to feed this thing, do an extension
cord.
Each
switch and
receptacle needs to be commercial grade - remember Bill's above $25.00 box above? Price out the commercial grade switches, much less just one mini-breaker and you just went over budget. The
NEC is very specific about not using home owner grade devices in a theater or place of assembly. As a given the above
switch box probably won't be using commercial grade receptacles, but it is a
UL listed device, your's will not be and needs to comply in all possible ways with the
NEC.
Next, you need an indicatator light for each
circuit and one for the main
power in. This is useful in letting you know what is live and at very least in the box being live a code requirement for a
portable distribution box.
By code, electrical boxes are not structural nor are you allowed to be using a
line voltage pendant or remote switching device. The
conduit boxes need a painted plywood backing if attached together and if at all possible this thing needs mounting to a table and or wall so as to prevent anything bad from happening should it fall over for instance.
That's all preliminary type stuff, again eyes on site will show proper strain reliefs, and lots of other stuff not covered. Also, anything above doesn't even mean that it's accepted by your local code or a inspector just seeing the gear won't tag it for violation of the code because it's a tricky thing what's permissible or not. Beyond all this, get what you create inspected by the supervisor responsible for the theater and have that person sign off on your work. Liability of this box must be with the person on paper responsible for it and all lives assembled within it.
Highly not recommended to do this project, have your brother look over his copy of the
NEC about these concepts expressed, verify the ideas and inspect the gear you currently have to do this project with.