All new wiring design

[TallTimbers]

I am going to be wiring my new building sometime shortly after the 1st of the year. My building will have a finished metal liner in it and I have planned to run all my electrical in conduit that will be surface applied to the metal walls. I have done wiring before but never in conduit. Can anyone help point me in the right direction. I know i need to use the single solid #12 wire.

How many wires can be in conduit?
Can more than one circuit run in the same conduit?
Use the box as ground?

I had a lot more question when I thought to post this but have forgotten them. Any websites with codes, set ups, or any input you all have would be great. Thanks in advance!

 

[madosta]

Just some thoughts.

You can use stranded over solid as it will be easier to pull and work with in the conduit. It takes more work to get it trained in the panel though.

The number of wires and circuits depends on a few things. Fill, derating, junction box fill limits, etc.

I would pull a separate green ground and not rely on the conduit as your ground - although it can be done.

 

[pattenp]

Here's some basic fill numbers for EMT.
THHN/THWN
#14 1/2"=12 3/4"=22 1"=35
#12 1/2"=9 3/4"=16 1"=26
#10 1/2"=5 3/4"=10 1"=16

 

[ChevyIINova]

There is a lot more to this then it first seems. Many layers of code to be deciphered!! I just finished a very similar project to this.

You will love this online calculator http://electrician2.com/calculators/rf_calculator.html

Be aware that just because code says you can put like 16 12Ga wires in 3/4 conduit doesn't mean you want to plan for that many. You need pull boxes after every 360 degrees of conduit bends. spend some hours on www.mikeholt.com and his YouTube videos. It will be time well spent. I am not a fan of 3 wire 110/220 wiring which effects the number of conductors in your conduit. I chose to stay 2 wire. Make sure you completely understand 3 wire before you decide to share one neutral for two hots just to save space for fill rate.

Fill rate is only one aspect of the design. Use http://www.electrician2.com/ and i found a bunch of info on http://www.electriciantalk.com/

I used 3/4 inch EMT for my 2000 sqft shop. As far as cost and fill rate it was the best compromise for me. I have 200 amp service in my shop outlets are every 10 feet around the perimeter and 4 220V welder outlets. lots of lights, a compressor and lift.

 

[pattenp]

There is a lot more to this then it first seems. Many layers of code to be deciphered!! I just finished a very similar project to this.

You will love this online calculator http://electrician2.com/calculators/rf_calculator.html

Be aware that just because code says you can put like 16 12Ga wires in 3/4 conduit doesn't mean you want to plan for that many. You need pull boxes after every 360 degrees of conduit bends. spend some hours on www.mikeholt.com and his YouTube videos. It will be time well spent. I am not a fan of 3 wire 110/220 wiring which effects the number of conductors in your conduit. I chose to stay 2 wire. Make sure you completely understand 3 wire before you decide to share one neutral for two hots just to save space for fill rate.

Fill rate is only one aspect of the design. Use http://www.electrician2.com/ and i found a bunch of info on http://www.electriciantalk.com/

I used 3/4 inch EMT for my 2000 sqft shop. As far as cost and fill rate it was the best compromise for me. I have 200 amp service in my shop outlets are every 10 feet around the perimeter and 4 220V welder outlets. lots of lights, a compressor and lift.

With multiwire branch circuits using a shared neutral the use of line to line loads have to meet certain requirements, otherwise only line to neutral loads are to be used.

 

[ChevyIINova]

Another link I liked

http://www.mikeholt.com/instructor2/img/product/pdf/1259687476sample.pdf