assessment for L2 EVSE in garage

I wasn't sure where to post this, and after looking around I didn't find answers.

My garage is detached from the house and has two 110 VAC lines within a single cable entering the garage. The garage has two breakers in my breaker panel. The panel is located in my finished basement and there is NO option to run new lines to the garage.

I believe my leaf usage will be such that L1 charging is suitable 99% of the time. Otherwise it will be public stations. Our home is newly constructed within 10 years. I would rewire the outlets to use the screw terminals instead of quick connects on the 110 Sockets.

That being said, I would like to assess my garage for suitability of a L2 EVSE. Max charge rate is not a concern. I see clipper creek has a lower power 15A L2.

My garage has two 15 amp lines. One line covers five 110 outlets. There are two garage door openers, stereo, drill battery chargers, once in awhile I run a saw or charge the lawn mower. The other circuit supplies 3 light sockets with CFL bulbs.

Does anyone know if my supply to the garage can be shared with the existing equipment and a low power L2 EVSE?
http://www.clippercreek.com/store/product/charging-station-lcs-20-level-2/" onclick="window.open(this.href);return false;

Thanks

vwDavid said:

That being said, I would like to assess my garage for suitability of a L2 EVSE. Max charge rate is not a concern. I see clipper creek has a lower power 15A L2.

My garage has two 15 amp lines. One line covers five 110 outlets. There are two garage door openers, stereo, drill battery chargers, once in awhile I run a saw or charge the lawn mower. The other circuit supplies 3 light sockets with CFL bulbs.

Does anyone know if my supply to the garage can be shared with the existing equipment and a low power L2 EVSE?
http://www.clippercreek.com/store/product/charging-station-lcs-20-level-2/" onclick="window.open(this.href);return false;

Thanks

Click to expand...

Short answer on L2 on your existing wiring is most likely NO. L2 is 240vac. Some will say it could be possible if both 120v/15amp lines are on different phases in your panel. However, the max draw on either leg could not exceed 12 amps (80% standard) and the EVSE should be on a separate, dedicated circuit. In addition, the gauge and length of the wiring to your garage should be evaluated to ensure it's heavy enough for a long duration heavy continuous draw.

Thanks,

I think if I measure the voltage hot to hot and it reads 240 then they are on different phases. I will check the gauges and ask an electrician at work.

Can you make it work? Probably....

Will the installation be up to code? Unfortunately, not at all, not even close.....

vwDavid said:

My garage is detached from the house and has two 110 VAC lines within a single cable entering the garage. The garage has two breakers in my breaker panel. The panel is located in my finished basement and there is NO option to run new lines to the garage.

My garage has two 15 amp lines. One line covers five 110 outlets. There are two garage door openers, stereo, drill battery chargers, once in awhile I run a saw or charge the lawn mower. The other circuit supplies 3 light sockets with CFL bulbs.

Does anyone know if my supply to the garage can be shared with the existing equipment and a low power L2 EVSE?
http://www.clippercreek.com/store/product/charging-station-lcs-20-level-2/" onclick="window.open(this.href);return false;

Thanks

Click to expand...

I would believe that it cannot. Feeding a L2 charger at 240 volts would require a breaker split across the two sides of the line, which would probably be disallowed for feeding the 120 volt circuits in the garage.

You didn't mention if the circuits are 15 or 20 amp, and what gauge of wire feeds them, but it sounds like they may be just 15 amp circuits probably with #14 wire.

You may want to revisit the "no way" to run additional circuits, because that is probably what you need. Another option might be a second power panel in the garage, with a feed from the main breaker panel (presumably near the utility meter outside).

You need a 20 amp feed for the 15 amp CC EVSE.
Best shot is EVSE Upgrade and use 12 amp setting.
Don't expect to run much else.

Thanks. Just checked the breakers and they are only 15 amps each so looks like L2 is out unless a new line is run.

I am assuming local code requires burial of a line and conduit and this requires crossing concrete walk ways etc etc so I don't really want to get into that. Wondering if I could install and outdoor junction box below the external meter connection and run and outdoor extension cable to the garage that does not have to be buried. Just thinking out loud.

Thanks guys.

Since the EVSEs seem to always use two Hot wires, a Ground, and no Neutral, you may have one option. Remove one line from 120 volt service, convert it to a 15 amp 240 volt line using the Hot and neutral wires as two Hots (label the re-purposed Neutral!) and use the EVSE Upgrade unit, set to 12 amps as suggested above. Question for the experts, though: can you double the voltage with the same amp rating in this case?

If the existing conduit is large enough to replace the wire with #10 or #12 you you could easily go 30 or 20 amps for a 24 or 16 amp L2 EVSE.

Let's take him at his word and assume that replacing wires isn't an option. Shouldn't it be possible to convert one 120 volt 15 amp circuit to one 240 volt, 15 amp EVSE feed circuit? Would it have to be hardwired to the EVSE?

Tunnel, baby, tunnel!

http://www.askthebuilder.com/tunneling-under-sidewalks-and-driveways/" onclick="window.open(this.href);return false;

vwDavid said:

Thanks. Just checked the breakers and they are only 15 amps each so looks like L2 is out unless a new line is run.

I am assuming local code requires burial of a line and conduit and this requires crossing concrete walk ways etc etc so I don't really want to get into that. Wondering if I could install and outdoor junction box below the external meter connection and run and outdoor extension cable to the garage that does not have to be buried. Just thinking out loud.

Thanks guys.

Click to expand...

Take a look how the old lines are buried. Are they buried in a conduit? If so, would look at removing both of the old lines and replacing with a single heavy-gauge cable to support both legs of 240v to a sub-panel in your garage. Then reconnect your existing garage wiring to new breakers in the sub-panel and have proper 240v for an EVSE. This would likely support a full 240v/30 amp for a meaningful L2 EVSE and other higher draw tools. Should be thinking of this as a property investment. Will cost a little more up front but pay dividends in the long run.

vwDavid said:

... My garage is detached from the house and has two 110 VAC lines within a single cable entering the garage. ...

Click to expand...

That would be very unusual.
What kind of cable is it?
How does it enter the garage?
Is it coming out of conduit or was it direct buried, such as UF cable?

You really should have someone knowledgeable enough to ask and investigate the answers to such questions look at it.

Trying to do it yourself with only input from MNL is a bad idea.
But you will get better input if you post links to photographs that help answer the questions, especially if you are unclear on the questions or what you are seeing means.

LeftieBiker said:

Let's take him at his word and assume that replacing wires isn't an option. Shouldn't it be possible to convert one 120 volt 15 amp circuit to one 240 volt, 15 amp EVSE feed circuit? Would it have to be hardwired to the EVSE?

Click to expand...

He has two hot, neutral and ground. He has 240v just not the amp rating to drive the 15 amp EVSE. He can go 12a 240v EVSE or pull wire.

DNAinaGoodWay said:

Tunnel, baby, tunnel!

http://www.askthebuilder.com/tunneling-under-sidewalks-and-driveways/" onclick="window.open(this.href);return false;

Click to expand...

Lots of commercial contractors do this and much more every day.
I have seen drills go over 100' laterally, pull a cable through, then pull conduit of choice.

Same with replacing sewer pipe. Contractors put a cable through then pull new pipe as the pulling head cuts and splits even cast iron pipe.

If the OP is lucky the electrician will use a locator to map the existing connection and find a slip pipe under the hardscape.

smkettner said:

He has two hot, neutral and ground. He has 240v just not the amp rating to drive the 15 amp EVSE. He can go 12a 240v EVSE or pull wire.

Click to expand...

That is a possibility, but with it being fed from two 15 amp 110V breakers in the panel in the basement it would not be per code because the circuits would be sharing the neutral.
Possible his single cable is some unusual four conductor cable with ground (s) but that would be strange.

His electrician friend from work or some other qualified person needs to look at it.

I assume it was code at the time. Easy part is to swap on a double breaker.
I have a few of these that were as built in 1973 as they are for general 120v circuits with a common neutral.

I switched from Uverse internet to Time Warner. I never had service so they had to run the line. It took then about 30 minutes to go under my sidewalk! The installers have specialized tools that make running under sidewalks very easy. They ran some sort of plastic conduit.

I do not believe in hanging over workers shoulders so I did not see the actual install. All I can say is they knocked on my door in a very short time. I used to have armed cops watching me work so I know what it is like.

Just checked, the single large black cable feeding through a conduit from my house to the garage has 3 conductors and a ground and are larger in gauge than the standard wiring in my garage.

Inside the single black cable is a black conductor, red conductor, white conductor, and ground. The white is connected to the to white neutrals of the two white 110 circuits in my garage. The black is connected to one hot of the one 110 circuit and the red is connected to the black/hot of the other 110 circuit and I assume this black line traces back to the two 15 amp breakers in my panel.

I do see I will need professional advice if I go further.

vwDavid said:

...
Inside the single black cable is a black conductor, red conductor, white conductor, and ground. The white is connected to the to white neutrals of the two white 110 circuits in my garage. The black is connected to one hot of the one 110 circuit and the red is connected to the black/hot of the other 110 circuit and I assume this black line traces back to the two 15 amp breakers in my panel.

I do see I will need professional advice if I go further.

Click to expand...

That actually sounds promising.
But yes you need help from a knowledgeable person.

Why a contractor would put in a conduit and a 240V cable but then violate code and connect it to two 15 amp 110V breakers in the panel in the basement is mind boggling.

But it might not cost too much to fix it and get you L2 charging in the garage.