Saturday, April 8, 2017

Office / Shop: Electrical

At some point in the past, the shop building had a single 120V 20 Amp circuit for outlets along the wall (power from the house's main panel). Then later someone came in and cut the wire at the end of the conduit and at each outlet... to probably make $2 from copper recycling and screw over the next homeowner. Makes sense...

Rather than try and get the woefully inadequate 20 Amp circuit legal (that panel was fugly), I went all out:
New panel at the shop.
240V 60 Amp rated wiring from the house.
Overhead light in office.
Two dedicated 20 Amp in the office supplying power to 6 outlets (one of which is in the ceiling for mounted projectors).
Overhead 20 Amp outlet in shop (primarily for a light).
One dedicated 20 Amp in the shop supplying power to 3 outlets.
One dedicated 20 Amp mounted outside near the roof line for security camera and Christmas lights.
NEMA 14-50 240V 50 Amp Outlet for the electric car charger.

I lost some of my early progress pictures, but there was more than enough work to have plenty left to share...

Outlets along the wall...

Close up of the wiring - it needs to be secured at least every 4.5 feet, within 12" of boxes, and within 8" inches of the single gang boxes. Please see NEC 334.30 or 314.17 for more info.

Please note I attached my wires behind my studs, but if you're going through studs be sure the hole is at least 1 1/4" from the edge. Please see NEC 300.4 for more info.

Outlet for projectors! And Star Trek light. :-)

Mounting the exterior 240V outlet for the car charger...

New panel with shop wiring (excluding the supply)!

Ground rods are freaking 8' long, and you need two of them! (Spaced > 6 ft apart.)

The first 7' go in easy enough, and then not so much...

The T-Post driver actually worked well for awhile, but towards the ground I had to resort to the sledgehammer. Slightly crooked, but close enough!

A photo of one of the wall outlets. You can see the ground wire being routed through the siding out to the ground rod outside.

Using the electric car to pick up the 6/3 cable...

It's always scary pulling off drywall to see what's underneath. And this house was no different... How much f'd up stuff do you see?

The wires tied together behind the wall? The air vent blowing cold wet air directly into the wall? The inexplicable reason they couldn't have a continuous stud? I removed the pitiful amount of insulation in there to do the wire work, but it wasn't much.

Here is my progress on bringing the mess up to code... And my new 6/3 cable being routed from the panel into the crawl space. (In the photo I attached the wires to the plywood, but I moved those to the studs to minimize chance of nails/screws going in them from the outside.)

Got the insulation in and new drywall up! I hate that conduit sticking out, but that will be something to clean up later.

The new 6/3 cable into the house panel!

Stripping back that UF-B cable is a gigantic pain. The best approach I found was to use my snips to slowly cut between the wires, then it was easier to get the UF-B jacket off the individual wires. But it still sucked.

The wire dropped down from the house electrical panel into the crawl space, then through the crawl space nearly the entire length of the house to one of the vents. By code the cable can't be laying on the ground in the crawl space, so I used 1 1/4" EMT 1-Hole straps to attach it to the supports underneath.

2" electrical conduit brings the wire from the crawl space into my trench to the shop.

Trench needed to be minimum 18" to the top of the cable.

I was going to use the existing 2" conduit at the shop to bring the UF-B in, but apparently it was 2" water pipe and thus illegal. I replaced it with a 2" LB Conduit Body and actual electrical conduit. It looks better at least...

The final wiring within the shop! The UF-B cable has a straight shot from the LB Conduit Body into the panel - which is a good thing because that cable is hard to bend. You can also see my two 6 gauge ground wires going out the bottom of the panel on their way to the ground rods.



 The car charger connected to the new outlet, so beautiful!

And it's so much nicer that I can take a drive to town and back and charge in 1 hour as opposed to 6!

I haven't been keeping track of costs, so these are estimates:
Permit ($97.40)
Electrical Panel ($60)
Panel Cover ($20)
5x 120V 20 Amp Breakers ($25)
240V 50 Amp Breaker ($10)
2x 240V 60 Amp Breaker ($20)
Main Breaker Tiedown Clip ($8)
6x 3/8" Cable Clamp Connectors ($5)
1 1/4" Cable Clamp Connector ($5)
1 1/2" Cable Clamp Connector ($5)
20 Amp Switch ($3)
11x 1-Gang Box ($10)
Round Box ($1)
125 ft 6/3 with ground UF-B ($307)
250 ft 12/2 Solid NM-B wire (only had 2 feet of wire extra at the end) ($61.47)
6 ft 6/3 Romex wire ($15)
25 ft 6 ga Solid Copper Wire ($18)
4x 20 Amp GFCI Tamper Resistant ($80)
1x 20 Amp GFCI Tamper Resistant Weather Resistant ($20)
6x 20 Amp Outlet Tamper Resistant ($36)
Exterior Enclosure for 120V outlet ($30)
Exterior Enclosure with NEMA 14-50 outlet ($40)
Ground Rod ($11)
Ground Rod Clip ($5)
Wire Staples ($5)
30x 1 1/4" EMT 1-Hole straps ($60)
2" x 10' Electrical Conduit ($7)
2x 2" Electrical 90 degree Elbows ($7)
2" LB Conduit Body ($35)
2" Conduit Clamps ($10)
Total: $1016.87
Let's add 10% for some sales tax I'm missing and stuff I forgot:
New Total: $1118.56
Let's add about $100 for stuff I bought that was a complete waste.
Actual cost: $1218.56

Not especially cheap, but it's a fraction of the cost of the quote I got to hire an electrician to do the work and I'm very happy with the final product.

Lessons learned...

Even though this is an exterior shop - it is at a residence, I made the expensive mistake of initially not buying all Tamper Resistance outlets. If the electrical is at your home, you must use the Tamper Resistant outlets. (At least if you have the same code requirements as me...)

The panel I bought did not have a main cutoff, but it was required for my situation. The solution was to put in a 60A breaker to backfeed the electricity into the panel. And then use a main breaker tiedown clip to "doubly" hold it down. Next time I would have bought a panel with a built-in main cutoff.

I already mentioned this, but the one piece I tried to re-use from the existing setup was the conduit in the shop. Make sure you use electrical conduit, not plumbing!

(As I've said in previous electrical work posts, I'm not an electrician. What I'm sharing was permitted and approved by an inspector and it hasn't burned my house or shop down, but I don't guarantee anything I say. Use this post as nothing more than another data point on your quest to do your own electrical work.)

Totally unrelated, but if you leave Doom 2 idle for an hour and then come back and finish the level, it mocks you for your time.


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