Best options for adding electrical?

[Bruce Walters]

I'm a beginner that is building out a work space in a garage (the space is shared with vehicles). After putting together my HF dust collector, I quickly realized that both available circuits in the garage are 15 amps and the DC pulls 20.

I obviously need to get more power into the garage. I'm far from an expert on electricity and I'm looking at a few different options:
1) Verify that all the wiring is 12 gauge and swap the circuit breakers to 20 amp
2) Run one (or more?) 20 amp circuits into the garage from main panel (or should that be 30 amps?)
3) Have a sub-panel installed in the garage (100 amp?)

The sub-panel would be best, but also the most expensive. I'd plan on having an electrician do any of the above.

Any recommendations or different suggestions?

Additional details in case they are relevant:
I currently have a 240V/50amp line going to the garage for charging an electric car
Current tools:
15amp table saw
15amp miter
15amp benchtop planar
10amp benchtop jointer
20amp HF DC

Because the space also functions as a garage, mobility is important. I don't see the ability to move to "real" jointer/planars in this space. I may eventually upgrade to a 220V table saw, but I'd be able to use the existing car outlet for that.

Thanks in advance for thoughts.

[Frank Pratt]

Put in a subpanel. It won't be much more, & maybe less, that running a bunch of individual circuits. You don't need a 100 panel though, unless you're going to do electric heat. 50A should be plenty.

[Andrew Seemann]

Agree on not needing a full 100A. On my current and last shop, I ran 100A wire to them but only put in a 60A breaker in the main box (100A breakers are typically expensive). I have never popped the 60A breaker, and I have a 3HP table saw, 3HP dust collector, 3HP planer, etc. At my parents, we only had 100A service for the whole house and had 50A going out to the shop from that. We never blew either the 100A fuses or the 50A fuses, and the old man had a welder, compressor, 2HP table saw, etc. 100A is a remarkable amount of power and difficult for one person to use in a shop without electric heat or seriously huge equipment.

[Doug Garson]

I agree at least partially with Frank. Option 1 is highly unlikely and option 2 might be more expensive than 3. I'd have my electrician quote both 50 amp and 100 amp panels, depending on how long the run is, the larger panel and heavier gauge wire might not be much and estimating both would be easy, if the difference is not great gives you lot's of room for future expansion like electric heat, air compressor, lights, fans etc. . I'd also ask the electrician if you can tap off the car charging circuit assuming you can limit shop time to when you aren't charging or vice versa.

[Dave Cav]

50 or 100 amp sub panel off your main, then you can hook up the branch circuits yourself. Depending on where your main panel is located it shouldn't be too expensive to pull one circuit off it and connect to a sub, depending on how the wire has to be routed. Where's your main located?

[Thomas Crawford]

The cheapest option is to turn the 50amp car charger into a subpanel and branch off of that (including the car charging socket). Downside is you couldn't charge the car and do anything else at the same time.

[Bruce Walters]

My main is in the basement on the opposite side of the the house -- I'm estimating it's a 30-40 foot run, but no major obstacles in running new line.

I'm giving serious thought to using the existing car line to feed the sub-panel. It's 6 gauge, so will support 60amp service. I don't have the vehicle in the garage when running any power tools, so dual charging & shop-work isn't an issue.

On the flip side, I've got a 2 year old and another one on the way. It's somewhat attractive to be able to shutoff and lockout power to the shop tools when I'm not in there.

[Andrew Seemann]

I have my electric in the shop set up with a subpanel for the machines controlled by a breaker in the main shop subpanel, so I can drop the power to the machines when I leave the shop or whenever I have little visitors, without killing power to the lights and fridge and heat and AC. I very much like that configuration; it gives a lot of peace of mind. You probably don't need to go to that extent, but having the subpanel set up so you can drop the breakers to the machines/circuits you want to keep little ones away from is nice. You can also have the subpanel put in with a main breaker, and drop out power to the whole thing as well.

[ray grundhoefer]

if the cable going to your car charger only has 3 wires, 2 hots 1 ground it cant be used for 120 volt receptacle. the labor difference between 60 amps or 100 amps will be minimal. If you find the need to upsize later you will end up paying twice

[Lyndon Klassen]

I have my shop currently running on a 30amp breaker. 2hpnsaw. I think a "1.5" hp dust collector. Lots of lights AND an electric construction heater. 30 amps. Can you believe that.

[David L Morse]

Have you tried to run your HFDC on a 15A circuit? It should work.

In it's stock configuration that DC will draw about 12.5A with the inlets wide open. Add some hose and a tool and the current will be close to 10A.

Note that the 16GA power cord has a 15A plug, not 20A.

[Robert Engel]

My advice as a non-electrician:

A subpanel is the best way to go. I'm sure the electrician will suggest this. ;-) If he doesn't, get a second opinion. LOL

40A is adequate unless you will have some 5HP machines, 60A better, 100A overkill.

Put your DC on a dedicated circuit.

Have at least 1 220v circuit for your future cabinet saw & planer ;-) ;-).

Run circuits in exposed wall mounted conduit. You or your mate may object, but you can always paint it. But is gives you flexibility to add, change circuits. The electrician will like you, too.

If I had to do over, I split the outlets and make the top and bottom different circuits. You do this by running 2 hots and splitting off to top and bottom of the outlet. Or you can put in a 2 gang outlet box and alternate outlets. Either way, then you can plug a shop vac into the same outlet as, say, a miter saw not worry about overload.

Upgrade your lighting if you haven't already done that.

Lastly, hire an electrician............oh you already did that.

[Rod Sheridan]

As has been indicated, your car charger probably doesn't have a neutral so you cannot use it for a sub panel feed.

A 60 ampere feed would be more than adequate, my shop has a 30 ampere feeder for 4HP machines and a 1.5 HP cyclone. Lighting is not on the shop feeder, I have a 15A feed for that from the main panel.

As all my shop receptacles are on a multi-wire branch circuit, I have a single locking disconnect switch that feeds all the machines except the cyclone which is on a separate circuit.

Of course now that my kids are in their thirties the switch hasn't been opened in more than a decade.....Rod.

[Bruce Walters]

Have you tried to run your HFDC on a 15A circuit? It should work.

In it's stock configuration that DC will draw about 12.5A with the inlets wide open. Add some hose and a tool and the current will be close to 10A.

I tried running it off both 15A circuits I currently have available in the garage. Both tripped within 2-3 seconds. Very little else (if anything) was currently drawing current at the time.

[Jim Becker]

Those two garage circuits may have other things on them if it's a typical home build. I agree with the sub-panel route as the best possible solution. One run back to the main panel and then flexibility for your woodworking needs away from already installed house circuits which can be "wonky", depending on how they were designed. A sub-panel and then simple surface mount with PVC conduit makes for a very easy install that's also easy to adapt to changes.