The big shop electrical upgrades thread [long, 56 pics]

[FliesLikeABrick]

Even as high as you have your panel, it will be still be subject to physical damage. A piece of 1" EMT from the panel to a box at the intersection of the attic/workspace is basically all you'll have to do. It will even look more professional.

You also need to support all your EMT down feeds within 36" of the outlet/switch.

Thanks. The SER cable won't fit in 1" EMT but your point is well taken.

Indeed, it isn't shown here (maybe in the final pictures) but almost all of the EMT downfeeds do have support in the middle now

 

[FliesLikeABrick]

Are you running the quad GFCI outlets on two circuits in each quad, or alternating circuits? I prefer having two circuits for each quad, but that means they need to be on a common trip.

Both circuits are present in each quad box. They shouldn't need to be common-trip if they are on separate neutrals, but in my case I do have it wired as a multi-wire branch circuit with common trip (although of course the neutrals are separate once downstream of the first GFCI on each branch)

 

[rabler]

My fault, shouldn't try to play code police! I'm confusing separate receptacles from when you split a receptacle (module) into two separate outlets each on a different circuit. I've used MWBC's but prefer isolated breakers to reduce what does get shut off by an overload on one circuit.

Nice job overall. And an impressive job of being up to speed on the codes. I just recently picked up a copy of the 2020 NEC, as I'm getting ready to wire a new shop myself, and trying to brush up on the more modern codes, especially as I'm putting in a RPC, and a 3 phase distribution panel as well as in-floor outlets both single and 3 phase. Since it is a new building I can do most of the wiring in-wall, but the wireway/trough does have a certain appeal.

 

[FliesLikeABrick]

My fault, shouldn't try to play code police! I'm confusing separate receptacles from when you split a receptacle (module) into two separate outlets each on a different circuit. I've used MWBC's but prefer isolated breakers to reduce what does get shut off by an overload on one circuit.

No worries - indeed I check in occasionally on your thread on your building projects. Part of the reason I do MWBCs in some places (not for these GFCIs) is because I know that at some points I may want 240v available at a bench for experimentation or testing a 240v component. Being able to tap 240v from two separate 120v receptacles -- which will properly trip together if overloaded -- is part of the reason I leaned towards MWBCs in this room.

For the GFCI quads though, I should have just done GFCI breakers from the start. If I ever need 2x gray GFCIs somewhere else in the shop, maybe I'll pull these out and replace them with GFCI breakers (either two separate or one common-trip since that would also allow for experimentation and bench testing 240v, whereas two separate outlets or breakers would not)

 

[NCjeeper]

Great work there. How many months did it take to go from basic to awesome shop?

 

[FliesLikeABrick]

Great work there. How many months did it take to go from basic to awesome shop?

I had the small lathe, mill, and temporary wiring to the improved lighting for a few months, using temporary power solutions. Then started moving on the electrical upgrade plans

Looking back at the timestamps on these pictures I started the work on the attic walkway in mid- March, and finished the back shop in mid-May. That was probably 85% of the project and involved most of the problem solving. Evenings and weekends after work, family plans permitting. Once all the material was here, there was good incentive to get it hung and off the floor.

The smaller stuff in the garage and elsewhere has been ongoing in bits and pieces since then, as requirements evolve.

 

[zuhnc]

@FliesLikeABrick - Are the panels a sub-feed from somewhere else, or are they a primary panel from a service feed from the meter base? If a sub-fed panel, the neutrals and grounds should have been bonded in the primary panel, and NOT in the sub-panel. Cannot have two (or more) ground/neutral bonds. Also, I see a lack of insulating bushings on the conduit fittings where the wires enter the various components, especially the VFD box. Nice installation.

 

[FliesLikeABrick]

@FliesLikeABrick - Are the panels a sub-feed from somewhere else, or are they a primary panel from a service feed from the meter base? If a sub-fed panel, the neutrals and grounds should have been bonded in the primary panel, and NOT in the sub-panel. Cannot have two (or more) ground/neutral bonds. Also, I see a lack of insulating bushings on the conduit fittings where the wires enter the various components, especially the VFD box. Nice installation.

Thanks for your observations/feedback

These are subpanels fed from a main panel within the same structure; neutral is bonded to ground only in the main panel. The bonding screw in the subpanel was removed (or not installed in the first place, I can't remember if it was in a baggie of accessories); and a separate ground bar was ordered and installed in the subpanels.

Code specifies bushings are mandatory for 4awg-or-larger conductors, with the consensus being that this is to protect the conductors' own weight from abrading the insulation on a hard edge during installation and over time. This installation is not using any 4awg+ conductors except the SER cable which has the outer jacket and is not in conduit or conduit fittings subject to pulling/scuffing forces. The other situation in which they are required is for threaded RMC conduit itself (due to cut and/or partial threads being exposed), regardless of conductor size:





That all said, of course they can (and should be used) proactively beyond what code actually requires. I did use them anywhere I used 1" or larger conduit, and anywhere that wire pulls could be going over a hard corner on a fitting.

All of the box-to-box or box-to-wireway connections are made with chase nipples that offer similar protection



The VFD box is not covered by the code requirements for bushings because it is a non-hardwired appliance. That said, the cabling coming in is rubber-jacketed in a compression fitting instead of terminating in EMT or RMC in a manner that exposes a sharp edge (that individual conductors may get dragged over). Even if this SO cord was exiting threaded RMC, the outer jacket of the SO cord should provide the necessary protection (akin to a throat protector being used inside RMC instead of a threaded bushing) since the conductor's insulation is the interior of the two layers of insulation and it is not a conduit fitting. On top of all that, the terminal strip is REALLY close to the knockouts in the VFD, it was hard enough to get the wiring routed with proper termination, let alone sneak a bushing in there too

Thank you for your comments - they keep me on my toes and encourage me to double- and triple-check my understanding

 

[zuhnc]

Thanks for your explanations. Nice install. Can't ever have enough outlets, most on their own circuit breaker and wiring. I have all the outlets in my shop at 48 inches above the floor, all GFCI.
Have you thought about emergency power to the shop? Generator, proper transfer switch (NO backfeeding anything), separate emergency sub-panel, etc.
I used to live in Norfolk. Moved three years ago to mid-MO, after retirement. Less everything! Very nice.

 

[FliesLikeABrick]

Thanks for your explanations. Nice install. Can't ever have enough outlets, most on their own circuit breaker and wiring. I have all the outlets in my shop at 48 inches above the floor, all GFCI.
Have you thought about emergency power to the shop? Generator, proper transfer switch (NO backfeeding anything), separate emergency sub-panel, etc.
I used to live in Norfolk. Moved three years ago to mid-MO, after retirement. Less everything! Very nice.

I do have an extra small generator I was going to use for the shop, to keep some computer equipment on during extended weather events (our wireless ISP has a relay on our shop that serves other customers, plus our own network relies on hardware in the shop). Not 100% proper (transfer switch), but if I do it -- it will at least be with an interlock on the main panel and a proper inlet receptacle outside (no suicide plugs)

If the shop ever becomes a fruit-bearing business instead of a hobby, then yeah I would upgrade to a more-proper solution.

I'm actually sometimes a bit bummed that the shop has its own meter+service for two reasons:
- Can't use one generator to serve the shop and house together during power outages
- The shop has a perfect roof and sun exposure for solar, so we did a small install. However, due to the separate meters we aren't allowed to overproduce at the shop in a way that can credit usage at the house; and the house is very ill-suited for solar due to its roof pitch and shading from trees. We do charge our car at the shop, and all of our always-on computer load is in the shop - so it still made sense to do some solar there.