What to tell electrician?

[jpa2825]

Situation:

CURRENT
Detached garage approx. 20' from both A/C unit & Washer / Dryer (inside the house in basement along back wall w/ deck between back wall of house and detached garage

Regular outlet in garage (landscape lights are currently plugged into 1 of 2 outlets)

DESIRE
240v, 16A plug in same place for EVSE upgrade (rather than charging station)

What do I tell the electrician when I am getting estimates? Upgrade the current wiring / outlet to 240v, 16A? Put in a new outlet with 240v, 16A? Should I tell him what I am doing, or assume he will be clueless and simply ask for precisely what I need?

 

[essaunders]

Minimum, have him run a new 20amp 240v curcuit - if for EVSE upgrade, finish with a L6-20r (receptical)

I think you'll want to keep your existing 120v garage circuit.


I would suggest an alternate quote for running wire to support a 40amp circuit. Then you decide between what you need now and a little future proofing. Just running 8gauge wire doesnt require you to use a 40amp breaker or outlet but would simplify for rewiring for one later.

I see no harm in telling your electrician this circuit is to support EV charging.

 

[GlennD]

Have a separate 240V 20A circuit ran. The socket should match the EVSE you will be using. I started out with a Levitron EVSE that required a S6-20R so thats what i used. The ingeneer mod uses a twist lock connector so if that is your plan then install a matching connector. Number 12 wire would be adequate.

I changed to a 30A Open EVSE hard wired using number 8 wire and a 40A breaker. Since I lease I will have something that will use the extra power in my next car. I do not think I could go back to an gas car.

 

[Herm]

Suppose you eventually get two electric cars?

 

[planet4ever]

If he's going to have to trench between the house and the garage, I don't think the extra cost of using a heavier wire is going to be all that significant. Tell him to use wire that will support 40A, but put in 20A breakers and an L6-20 outlet for now. As everyone else has said, don't try to talk him into using your existing circuit.

You could save a few bucks on the wiring by putting in a second out-of-phase 120v circuit and using a "Quick 220", but don't go that route either. That's a useful lash-up for occasional or emergency occasions, but not something you want to design for long-term use.

Ray

 

[wwhitney]

If your detached garage currently has a single 120V circuit and you want to add a 240V receptacle, you can't just run a new circuit to the garage. As a separate building, it can only be served by one circuit or feeder. So you will need to run a new feeder to a small electrical panel and move the existing circuit over to a breaker in that panel. Also, since you now have a feeder instead of just a circuit, the garage will need its own grounding system, e.g. two ground rods connected to the grounding bar in the new panel.

Cheers, Wayne

 

[DaveinOlyWA]

definitely add a new circuit and if you can, i would go 40 Amp. the increased cost would be nominal compared to the overall cost of installation and does allow you the flexibility of having a 6.6 KW charger or even being able to split the line into two 20 amp charger circuits later.

it really all dependent on how much more power you can add to your panel

 

[smkettner]

Suppose you eventually get two electric cars?

Oversize the conduit to pull what is needed for the future.... could be 100 amps or more.
I agree with just pull a 20a circuit for now.

 

[jpa2825]

If he's going to have to trench between the house and the garage, I don't think the extra cost of using a heavier wire is going to be all that significant. Tell him to use wire that will support 40A, but put in 20A breakers and an L6-20 outlet for now. As everyone else has said, don't try to talk him into using your existing circuit.

You could save a few bucks on the wiring by putting in a second out-of-phase 120v circuit and using a "Quick 220", but don't go that route either. That's a useful lash-up for occasional or emergency occasions, but not something you want to design for long-term use.

Ray

Ray -- is your advice still the same if I don't have any more empty spots in my panel? Also, now realize I have 2 outlet boxes in my garage (along with a light switch next to 1 of the boxes). Does that make it any more likely that 2 of the 4 outlets is "out of phase" to make this possible?

 

[Deleted member 3147]

Ray -- is your advice still the same if I don't have any more empty spots in my panel? Also, now realize I have 2 outlet boxes in my garage (along with a light switch next to 1 of the boxes). Does that make it any more likely that 2 of the 4 outlets is "out of phase" to make this possible?

It is more likely that both boxes in the garage are on the same circuit breaker, especially if your home is more than 15 years old.

If they are on different breakers, it's 50/50 if they are on different legs or not, though it is an easy fix to move a breaker to put it on the opposite leg.

As for adding breakers to a full panel, depending on the panel, you may be able to replace some breakers with tandems (two 120V breakers in one) or quads (two 240V breakers in one) to free up some space. This is especially true on newer homes.

Posting photos of your panel and the paper glued to the inside of the cover may allow us to tell you.