Q for Electrical Gurus

[edigest]

I have what appears to be an AS3112 plug at the cabin -- don't ask me why ... it was built about 30 years ago -- see image below.

Is it safe to use an adapter with the standard Tesla NEMA 5-15 the comes with the M3?

This is the only adapter I've been able to find:

Australia AS3112 to USA NEMA 5-15R plug adapter.

Any suggestions appreciated.



This is the only plug within reach of the car:

 

[Petrlol]

I'd look at the gauge of the wires and swap to a supported outlet.

Assuming that's a dedicated recepticle I'm guessing you've got 2 hots and a nuetral.

I'd go with 2 hots and a ground (same thing as nuetral if going back to main panel)

That 250v 10amp is what's concerning to me... Wonder what the wire gauge is...

Hopefully you can get a nema 6-20 at least

 

[trm2]

I thought that looks like a 10-50 outlet, but was wrong. Disregard the original post here.

 

[Petrlol]

I thought that looks like a 10-50 outlet. Then, this adapter would work:

AC WORKS 1.5 ft. EVSE 50 Amp 3-Prong NEMA 10-50P Plug to 50 Amp Electric Vehicle Charging Adapter Cord for Tesla-EV1050MS-018 - The Home Depot

Even if that adapter fit the car would try to pull 32 amp on a receptacle that is labeled 10amp, with unknown wiring. Big time fire hazard!

 

[edigest]

Thanks for the reply!

I'm an aero-, not electical-engineer, so a little behind the power curve on this (no pun intended). If the wiring is 12-gauge it can handle NEMA 6-20, but if it is 14-gauge I'm limited to NEMA 5-15?

 

[trm2]

Even if that adapter fit the car would try to pull 32 amp on a receptacle that is labeled 10amp, with unknown wiring. Big time fire hazard!

Good point, I overlooked that. That could only charge at 8 amp then. I’d check the breaker as well as the wire.

 

[F14Scott]

What is the breaker or fuse upstream of your plug rated at? Total amps of the panel?

 

[Petrlol]

Thanks for the reply!

I'm an aero-, not electical-engineer, so a little behind the power curve on this (no pun intended). If the wiring is 12-gauge it can handle NEMA 6-20, but if it is 14-gauge I'm limited to NEMA 5-15?

Well even if it's 14 you may be able to get to 6-15. 240v is better than 120v by far!

Then you could get the Tesla adapter here:
Gen 2 NEMA Adapters

We really need more info though.

 

[NickFie]

It looks like it would work. Car will charge slowly. For example, my wife drove our S100D to our daughter's apartment last Thursday. Her then-fiancee, now husband, connected Mobile Connector to a 120 Volt 5-15 receptacle. The car charged at 12 Amps, limit for continuous operation of the 15 Amp rated outlet. The battery added 19 KWH over the following 18 hours.

Cautions:

- The receptacle appears to be exposed to weather. It may no longer be able to safely handle its rated electric load. Proceed with caution. Electrician's fee to review and renew the arrangement is likely to be a small fraction of cost to repair damage from electrical fire.

- Adapter rated at 10 Amps. The Model 3 5-15 adapter will pull up to 12 Amps, which could overheat the receptacle or adapter. You can use the outlet to charge your car with the following procedure:

A. Before attaching cable, bring up charging menu.

B. Enable Scheduled Charging. Specify start time a few hours in the future. You can change this later, the step ensures charging will not start until you've configured the car.

C. Insert receptacle adapter, then connect Mobile Connector with complementary 5-15 adapter. Finally, connect Mobile Connector with the car's charge port.

D. Return to charge menu in car. Set maximum current to 10 Amps, it likely shows 12 Amps as max. Note whether display shows 120 Volts or 2x0 Volts (220 or 240).

E. Disable scheduled charging. Charge will start after some seconds, current draw will ramp up slowly.

F. Check receptacle and adapter for overheating using the back of your hand, which is more sensitive. If you can find the lead connecting receptacle to breaker panel, check it with the back of your hand. Check at the start and then every 15 minutes for the first hour.
- Warm, but you can comfortably press your hand against it for 10 or 15 seconds, if acceptable.
- Too hot to rest to press the back of your hand, or burning smell? Discontinue charging immediately.​

- Not a problem if receptacle provides 220/240 Volts. The adapters can handle it, your car will charge at slightly more than twice the speed.

Be careful, and good luck!

 

[Sophias_dad]

Change that outlet to a standard US 240v outlet. Adapting it to a 120V outlet using that dongle is a really bad idea, if for no other reason than you are throwing away half the charging capacity, and limiting the charge rate to 10A on 120V will not really be worth the effort.

Check the wire gauge and circuit breaker and I'm sure someone here will give advice about which outlet to use.

 

[eprosenx]

I have what appears to be an AS3112 plug at the cabin -- don't ask me why ... it was built about 30 years ago -- see image below.

Is it safe to use an adapter with the standard Tesla NEMA 5-15 the comes with the M3?

This is the only adapter I've been able to find:

Australia AS3112 to USA NEMA 5-15R plug adapter.

Any suggestions appreciated.



This is the only plug within reach of the car:

View attachment 412704

Wow, that is a unique one!!! I wonder what the history is here? Can you please post more photos of the whole receptacle and the area it is installed as well as the circuit breaker panel? Do you know which circuit feeds it? Is it a dedicated circuit, or shared with other things?

I am curious what this was used for.

There is probably no way I would use it though. I would probably figure out what gauge / kind of wire it was connected to and install a new receptacle re-using the same wire if it was appropriate. If a dedicated circuit, the idea of switching it to a 240v circuit is a great one.

Thanks for the reply!

I'm an aero-, not electical-engineer, so a little behind the power curve on this (no pun intended). If the wiring is 12-gauge it can handle NEMA 6-20, but if it is 14-gauge I'm limited to NEMA 5-15?

If 12 gauge it will support 20a (16a continuous which is what the Tesla needs). If 14 gauge it will support 15a (12a continuous). Either can support 120v or 240v. You will get double the charge speed off the same wire at 240v vs. 120v so it is *highly* recommended. The receptacle types for 240v are 6-15 for 14 awg, 6-20 for 12 awg.

 

[wws]

Almost seems like some sort of weird NEMA 10-like variant (i.e., 2 hots + neutral to allow 120/240v operation) - but for a 15 amp circuit. If it were me, I'd convert it to a pure NEMA 6-15 (240v, 15 amp - 2 hots + safety ground) setup.

 

[edigest]

Many thanks for all the input. Since quite a few considerations have been offered -- not to mention, this thing has been sitting on the (out)side of the cabin for 30 years -- I think my safest course is to have an electrician look at it before I do any unattended charging.

 

[Rocky_H]

There is probably no way I would use it though. I would probably figure out what gauge / kind of wire it was connected to and install a new receptacle re-using the same wire if it was appropriate. If a dedicated circuit, the idea of switching it to a 240v circuit is a great one.

Yeah, that would be my idea too. Don't bother to try to come up with some hacked way to use a foreign outlet type that shouldn't really be there anyway. I would just consider that there is a wiring run in place, and that is my baseline starting point. Find out what gauge of wire it is, put on the appropriate sized two-pole breaker to make it a 240V circuit, and put the appropriate sized receptacle on the other end that you can plug a proper official Tesla adapter into.