Does the outlet have two straight openings (with ground above or below) or does one of the openings look like a sideways T?Hi, I may be a little confused. Today we have a NEMA 5-15 120 volt (common household outlet). Not sure if it's 15 or 20 amp yet--it's really cold out today.
According to Tesla's website, the most we could expect for 1 hour of charging is 3 miles of range. My commute is short but not that short.
Thanks!
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Help w sticker shock over adding amp to detatched garage
- Thread starter ebennett22
- Start date
Hi, I may be a little confused. Today we have a NEMA 5-15 120 volt (common household outlet). Not sure if it's 15 or 20 amp yet--it's really cold out today.
According to Tesla's website, the most we could expect for 1 hour of charging is 3 miles of range. My commute is short but not that short.
Thanks!
Does your garage outlet have the little horizontal slice off the upper left slice? Look at the picture I posted and see how its not a regular household outlet, but is quite similar. Tesla's estimates are conservative, the 5-15 gets my S 3 miles in MN cold, like 0F. The 3 is more efficient than the S
IMO if you are going to the trouble of running conduit either in the air or trenched over to the garage, you might as well install the largest circuit that your main panel can accommodate and prepare for the future as you say. Who knows, maybe you want a welder in that garage some day!
I would try to do as much work yourself to save money as others have mentioned. You could install the conduit (trenched or in air) to the electricians specs/liking and even pull the wire too. Pretty much do everything but land the connections in the respective locations and let the electrician do that.
Wire isn't super cheap, you'd likely need #1/#2 for a 100A connection at 240V and that will run you ~$1.50 per foot per conductor from a quick google search. That would mean at least $500-750 in wire alone, but it seems worth it to go for the 100A option since a 40A run would only save you $250-350 in wire and maybe a little in the breaker itself.
Oh and PS - Common "household" outlets will get you at least 5 miles per hour on the Model 3, it's not too shabby!
I would try to do as much work yourself to save money as others have mentioned. You could install the conduit (trenched or in air) to the electricians specs/liking and even pull the wire too. Pretty much do everything but land the connections in the respective locations and let the electrician do that.
Wire isn't super cheap, you'd likely need #1/#2 for a 100A connection at 240V and that will run you ~$1.50 per foot per conductor from a quick google search. That would mean at least $500-750 in wire alone, but it seems worth it to go for the 100A option since a 40A run would only save you $250-350 in wire and maybe a little in the breaker itself.
Oh and PS - Common "household" outlets will get you at least 5 miles per hour on the Model 3, it's not too shabby!
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It has 2 verticals and one round underneath. It's a common household outlet (another poster put an image of it in this string).
I had two 50 amp (14-50s) installed in my garage, that was almost 5 years ago. I agree with your kbecks, but I might do it differently now because the High Power Wall Connectors can now be daisy chained to share a 50 amp connection. In all but the most rare cases you could plug 2 EV's in when you get home from work and both would be full by the morning. Its just something to consider, you would be looking at about $1,000 for 2 High Power Wall Connectors, but less money for wire and potential panel upgrades.
I bet somebody will come out with a 14-50 splitter type device that is smart, that would be a lot cheaper because you could just use your mobile connectors on it.
One other thing, Tesla sells a 6-50 adapter and I think 6-50 wire is cheaper than 14-50 wire, so you'd save money and have an additional adapter.
I bet somebody will come out with a 14-50 splitter type device that is smart, that would be a lot cheaper because you could just use your mobile connectors on it.
One other thing, Tesla sells a 6-50 adapter and I think 6-50 wire is cheaper than 14-50 wire, so you'd save money and have an additional adapter.
This is true. 6-50 has one less conductor.
But, you may have to bring in a complete circuit with a neutral and replace the old circuit. You need the neutral fir 120v and it may be against code to have two breakers to turn off the power in a detached building.
gilscales
Banned
Here where I live the trench needs to be deep enough to have 18" of dirt over the conduit, to dig a ditch over 200 ft long you could rent a trencher, something like this would make quick work of the trench.
Walk-Behind Trencher, 18-27 hp, Track for Rent - United Rentals
BEFORE YOU DIG GET ALL UNDERGROUND UTILITIES SPOTTED BY CALLING 811, THE DIG ALERT HOTLINE
Ready To Dig | Georgia 811
Sorry for the yelling, haha, just want to make sure you call 811
I would use 1 1/2" conduit (1" for #6 wire is fine should you decide 50A or 60A is fine) to make pulling wire easier as this is a LONG run, putting together a plastic electrical conduit run could not be easier and its cheap, have all your wires ready to pull and pull as you go about every 30 feet or so would make it easier, just make sure you have a strong poly rope of about 5/16" or so and tie a strong loop at the connection end then run your wire through the loop about 12" double it back and tape it down really good, you'll have to start at the other end of a 250' rope and thread each pipe down to the next and glue up as you go but this should work well, you could even add wire lube to decrease the resistance when you pull it.
1-1/2 in. x 10 ft. PVC Schedule 40 Conduit-67488 - The Home Depot
1 in. x 10 ft. PVC Schedule 40 Conduit-67462 - The Home Depot
Your going to need 700 ft or so of at least #2 copper wire to minimize voltage drop over that length run plus I would run a ground wire of at least #6, you may find it cheaper to buy a 1000' bulk roll of #2 wire as its about 30% or so less in bulk but at about $1,000 this is by far the most expensive part of the project.
Southwire 1000 ft. 2 Black Stranded CU SIMpull THHN Wire-20502102 - The Home Depot
Your going to need a sub panel, some breakers, ground rods, armored ground wire and clamps, conduit and cement, rope, a trencher, other assorted items, all in you should be at less than $2,000 and if you are not comfortable hooking up the electrical you could have someone else do that part but really it is only 4 wires and if you are coming off of your main panel with a breaker then all you need to do is shut off the main breaker to kill the current to panel, pull a permit and have it inspected and if there are any issues then the city inspector will let you know, they are usually easier on home owners and will be more helpful when it comes to something like this.
If you decide you don't need more than a 50A sub panel you could get #6 wire and save about $600
Southwire 1000 ft. 6 Black Stranded CU SIMpull THHN Wire-20493305 - The Home Depot
breakers will be a little cheaper and maybe you could get away with 1" conduit and save there, its big enough for 4 #6 wires as far as the conduit as you'll be at about 25% fill but it just may be harder to pull the wire, number #6 is a lot more flexible though so should be fine.
32A draw will have approx. 5% voltage drop on #6 where #2 will be approx. 2% not a problem either way you go as it is recommended to size the wire for less than a 7% drop
Voltage Drop Calculator
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gilscales
Banned
I have used this trencher before and while I only went 40 ft in soft dirt I still could not get more than about 14 to 15 inches deep and had to dig out the rest with a trenching shovel, still made the job easier but if I had to do the 225' trench at least 20" deep to get that 18" minimum depth needed I would get the 36" trencher, it has more power and will go faster to boot.
swaltner
Active Member
If you do upgrade the service to the garage and want a way to make it "cheaper" bundle the service upgrade with a solar panel installation on the garage. If the service upgrade is required as part of a solar installation, you can take the 30% deduction on the whole solar installation and any required service upgrades for that. You'll spend more for the whole project, but the service upgrade will be a little less. 
gilscales
Banned
That is a really good idea!If you do upgrade the service to the garage and want a way to make it "cheaper" bundle the service upgrade with a solar panel installation on the garage. If the service upgrade is required as part of a solar installation, you can take the 30% deduction on the whole solar installation and any required service upgrades for that. You'll spend more for the whole project, but the service upgrade will be a little less.
Well there's the "now", and there's the "preparing for the future". If you want to future-proof, you probably need to bite the bullet, but I don't know that I would do that. I would probably go for the cheaper way and deal with losing your existing circuit.
You said you have a 120V 20A feed to that garage right now. The wire size is scaled by the amps, not the volts, so you can use an existing wire run and switch it from 120V to 240V by changing the end points, but you would be changing it over completely, so no regular lights or outlets on the end of it if you change it over to a charging circuit. That is your very cheap, easy, and up-to-code method that can give you some decent charging. You won't have a regular wall outlet anymore though if you can deal with that. To get around the darkness thing, you can get little battery powered ceiling lights with wireless switches at Home Depot or somesuch that are used for sheds or buildings like that which aren't wired for electricity, so that's your alternative there that isn't too bad.
75 yards is a pretty long run to trench. Just a thought, have you checked to see if your electric co has EV rates that can utilize a separate meter? It's possible that could be a better and or cheaper option.
On 110 with 15 amps I would see 4mph charging most of the time. That's workable if you can charge at work during the week and if you don't do a ton of driving on the weekends. That's what I did until I installed my 14-50.
Get home at 6pm, charge until 6am = 40 miles or so which may mostly cover your daily commute. Charge from 6pm Friday until 12pm on Saturday = 60 miles etc.
20 amp
If it looks like a regular outlet it is just 15. 20 amps have a slightly different prong.Hi, I may be a little confused. Today we have a NEMA 5-15 120 volt (common household outlet). Not sure if it's 15 or 20 amp yet--it's really cold out today.
According to Tesla's website, the most we could expect for 1 hour of charging is 3 miles of range. My commute is short but not that short.
Thanks!
On 110 with 15 amps I would see 4mph charging most of the time. That's workable if you can charge at work during the week and if you don't do a ton of driving on the weekends. That's what I did until I installed my 14-50.
Get home at 6pm, charge until 6am = 40 miles or so which may mostly cover your daily commute. Charge from 6pm Friday until 12pm on Saturday = 60 miles etc.
20 amp
I setup a 6-20 outlet using an old 240V 20A circuit intended for an air conditioner. The wires are the same as a 120V line (though hooked up differently) and it since it used the same breaker there were minimal changes. The total cost was $250 for the electrician and $25 in parts. This should be possible for a garage, though you would loose the existing 120 line.
Charging a Model 3 with a 6-20 works as advertised: as I type its accepting at 15 MPH. The only problems will be deep freezes and deep discharges.
Charging a Model 3 with a 6-20 works as advertised: as I type its accepting at 15 MPH. The only problems will be deep freezes and deep discharges.
fluxemag
Member
I ran the wire from the panel to the corner of the house closest the detached garage and put a NEMA 14-50 outdoor box/outlet there. Then I run the UMC cable under the garage door and it barely makes it.
Whether it's 40-Amps or 100-Amps, you are not really paying for the Amps but for the labor. A 100-Amp panel is probably under $50 and the wire from your main panel to the garage is under $2/foot. It's not really a challenging task other than that ingrained fear of a shock. The whole job should cost south of $500 including a trencher rental. I would recommend going to your town's building department to get a better understanding of the size of wire and how deep it needs to be buried and whether it needs to be in a pipe.
Alternatively, if you do all the work on the garage end and the trench work till the main house, then all the electrician needs to do is the final connection. That should save a lot and you never risk the "shock" that matters.
Alternatively, if you do all the work on the garage end and the trench work till the main house, then all the electrician needs to do is the final connection. That should save a lot and you never risk the "shock" that matters.
If you don't want to trench, you could run overhead lines from the house to the garage. You could also have another meter installed on the garage from the power company, which wouldn't require any change to the house wiring.
I think future-proofing yourself by running 100 amps of service to the garage is the best idea, as it isn't that much more expensive than running a 50 amp line to the garage from the house. Install a wall connector on a 60 amp breaker and plan on sharing that with a second wall connector in the future (if you buy a second Tesla). Also install a NEMA 14-50 on a 40 or 50 amp breaker for an additional car charging station, RV, welder, air compressor, whatever. Finally, install some regular 20 amp 120 volt outlets around the garage for incidentals.
I think future-proofing yourself by running 100 amps of service to the garage is the best idea, as it isn't that much more expensive than running a 50 amp line to the garage from the house. Install a wall connector on a 60 amp breaker and plan on sharing that with a second wall connector in the future (if you buy a second Tesla). Also install a NEMA 14-50 on a 40 or 50 amp breaker for an additional car charging station, RV, welder, air compressor, whatever. Finally, install some regular 20 amp 120 volt outlets around the garage for incidentals.
lencap
Member
Hi -
The NEMA 5-15 120 volt is indeed a standard wall outlet. The 15 or 20 amp is the amount of current the circuit will handle. The important point is that it's a 120 volt outlet, not a 240 volt outlet. Using a 120 volt outlet does indeed severely limit your charging ability. In fact, in cold weather the typical wall outlet may only provide enough power to warm the battery pack with little, or no, ability to charge the car's battery.
If you do need to run another line to the garage consider renting a trenching machine - they are often rented to install sprinkler systems. Not sure what the cost would be, but I'll bet it's a lot less expensive than having an electrician do the work! Another option is to install the charger on the outside of your house - skipping the extra run to the garage entirely. It would likely be far more cost effective to charge the car near your house, then park it in the garage after it's charged. Yes, there may be some issues in very cold or snowy weather, but it still may be a less expensive option. Also, when you are charging the car you can also leave the climate control turned on the keep the car heated. If you then direct the windshield air to the side windows and leave the fan on high, it will warm the windows on the car, preventing the windows from icing to the door seal when the window slides down to open the door for entry.
The NEMA 5-15 120 volt is indeed a standard wall outlet. The 15 or 20 amp is the amount of current the circuit will handle. The important point is that it's a 120 volt outlet, not a 240 volt outlet. Using a 120 volt outlet does indeed severely limit your charging ability. In fact, in cold weather the typical wall outlet may only provide enough power to warm the battery pack with little, or no, ability to charge the car's battery.
If you do need to run another line to the garage consider renting a trenching machine - they are often rented to install sprinkler systems. Not sure what the cost would be, but I'll bet it's a lot less expensive than having an electrician do the work! Another option is to install the charger on the outside of your house - skipping the extra run to the garage entirely. It would likely be far more cost effective to charge the car near your house, then park it in the garage after it's charged. Yes, there may be some issues in very cold or snowy weather, but it still may be a less expensive option. Also, when you are charging the car you can also leave the climate control turned on the keep the car heated. If you then direct the windshield air to the side windows and leave the fan on high, it will warm the windows on the car, preventing the windows from icing to the door seal when the window slides down to open the door for entry.
Another idea, if you do want to go completely rewire-free, and if the electrician will do it...
Convert the current line to 240V, at the highest practical amperage. This will be dictated by the actual wire gauge of that line to the garage. It doesn't look real good from here... you'd need 8AWG to get 20 amps 250 feet without exceeding 3% loss. 8 gauge wire won't directly fit into any 120V outlets, so they might well have stuck with 10 or even 12 gauge which would leave you with pretty dismal charging.
The real magic is how to get the 240V back to 120v for your handful of low-power loads. For this you can use a european outlet and converter, to get a couple amps at 120V... Sadly, you aren't likely to be able to get an electrician to set this up, since you are supposed to have a dedicated line to your ev charger.
Convert the current line to 240V, at the highest practical amperage. This will be dictated by the actual wire gauge of that line to the garage. It doesn't look real good from here... you'd need 8AWG to get 20 amps 250 feet without exceeding 3% loss. 8 gauge wire won't directly fit into any 120V outlets, so they might well have stuck with 10 or even 12 gauge which would leave you with pretty dismal charging.
The real magic is how to get the 240V back to 120v for your handful of low-power loads. For this you can use a european outlet and converter, to get a couple amps at 120V... Sadly, you aren't likely to be able to get an electrician to set this up, since you are supposed to have a dedicated line to your ev charger.
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