Question about using 5-20 electrical outlet from pool filter for Model 3

[DirectorDisch]

Hi Friends,

Drove home to NJ this weekend, and noticed my in-laws have this plug in their yard, that they plug their pool filter into. Is there an adapter for this, and will it even charge the car? Thanks.

 

[Doc Brown]

That’s a NEMA L5-20P plug. Try this: https://www.amazon.com/Parkworld-Adapter-L5-20P-14-50R-Charging/dp/B07K66752L

you’d need to decide whether it’s worth the expense - it’s not 240v.

 

[Tam]

...this plug...

It has raised lettering saying "125V 20A" but that circular 3 prong format is not in Tesla store so you might want to go to Home Depot and buy a NEMA 5-20 which is quite popular in new homes and switch that out. Tesla store does have an adapter for that for $35.

It looks just like the popular ones in older homes NEMA 5-15 but it can also accommodate a horizontal prong where the other one can only accommodate 2 vertical prongs and no horizontal prong.

 

[Rocky_H]

Yes, looks like an L5-20.

That’s a NEMA L5-20P plug. Try this: https://www.amazon.com/Parkworld-Adapter-L5-20P-14-50R-Charging/dp/B07K66752L

That's kind of a bad idea. That would make you use the 14-50 Tesla adapter plug, which will tell the car it can draw the full 32A, and you would have to remember to dial down the current on the screen in the car.
So instead, you should just get the proper L5-20 plug from EVSEAdapters:

L5-20 Adapter for Tesla Model S/X/3 Gen 2

www.evseadapters.com

 

[davewill]

These little guys are easy to find at the local hardware store if you want to use your existing 5-15 adapter or Tesla's 5-20 adapter.

L5-20P to 5-15R/20R Heavy Duty Power Adapter, 20A, 125V, 6 in. | Eaton

This heavy-duty 6 in. plug adapter changes a NEMA 5-15P or 5-20P plug into a locking L5-20P plug for securing your network device into its outlet.

www.tripplite.com

 

[Rocky_H]

These little guys are easy to find at the local hardware store if you want to use your existing 5-15 adapter or Tesla's 5-20 adapter.

Oooh, dang! Yeah, totally. The L5-20 is the same three pins, but just in a different shape, so you can totally use a cheap little converter plug like this instead of a full $59 UMC adapter plug from EVSEAdapters. Don't know why that didn't occur to me.

 

[Janus]

That’s a NEMA L5-20P plug. Try this: https://www.amazon.com/Parkworld-Adapter-L5-20P-14-50R-Charging/dp/B07K66752L

you’d need to decide whether it’s worth the expense - it’s not 240v.

Converting to 14-50 comes with a bit of risk. The UMC, will start pulling at 32 (or 40, depending on version) amps, That's way more than the plug or cabling is capable of handling (ie 20/16 amps). Normally, that would trip the breaker, but regardless, it would still be a fire risk.

One would have to manually reduce the max amps to 16 prior to plugging in. (Remembering the 80% rule, and setting it to 16, not 20.) Then, each subsequent time, doublechecking that the car saved the reduced amps.

@davewill solution is much better. It converts from a twist lock to straight; while staying at the same voltage and amps. Then, when connected to the UMC using either the 5-15 or 5-20 plug, the car will never let one exceed the safe limit.

 

[TheRFMan]

There is no real advantage to using this outlet vs a standard household outlet. Its only advantage is that it’s a twist-lock, presumably to prevent the pool pump from being accidentally disconnected. if there is another regular outlet accessible, just use that with your UMC and save yourself the adapter purchase.

 

[Frank99]

To add on to TheRFMan's answer, that's also a GFCI protected outlet, probably with a very old GFCI. There's a non-zero chance that when you try to use it to charge, it'll pop the GFCI (Figure out where that is, possibly in the circuit breaker box; you should be able to just reset it if that happens).

So, I agree - there's little advantage to using that plug (with the right UMC adapters, you might get 5-6 miles of range per hour of charging, rather than 4-5), and a possibility of spending the money and still not being able to use the outlet. If it were me, I'd just use a normal outlet.

 

[Dmagyar]

My take is we have a forum with a cross section of participants, where many have little to no electrical background. The expectation is that most by participating in this and some similar forums will gain some useful information, but never fully understand what’s going on, and more importantly the “why” (of the National Electrical code). The expectation that circuit breakers installed of unknown age, and never “exercised“ are going to trip when needed most is wishful thinking at best.
Then for these same people to rely on the first person that comes along calling themselves an “Electrician” and offering to fix the situation for the lowest price again defies logic...

 

[Janus]

To add on to TheRFMan's answer, that's also a GFCI protected outlet, probably with a very old GFCI. There's a non-zero chance that when you try to use it to charge, it'll pop the GFCI (Figure out where that is, possibly in the circuit breaker box; you should be able to just reset it if that happens).

So, I agree - there's little advantage to using that plug (with the right UMC adapters, you might get 5-6 miles of range per hour of charging, rather than 4-5), and a possibility of spending the money and still not being able to use the outlet. If it were me, I'd just use a normal outlet.

There is one benefit: It's a dedicated circuit. While a standard 5-15 may not offer much greater speed, there's a high chance of tripping the breaker (depending on what other loads are on that circuit).

 

[eladts]

That’s a NEMA L5-20P plug. Try this: Amazon.com

you’d need to decide whether it’s worth the expense - it’s not 240v.

Don't use this adapter your Tesla will try to pull 32A if you won't limit it manually.

These little guys are easy to find at the local hardware store if you want to use your existing 5-15 adapter or Tesla's 5-20 adapter.

L5-20P to 5-15R/20R Heavy Duty Power Adapter, 20A, 125V, 6 in. | Eaton

This heavy-duty 6 in. plug adapter changes a NEMA 5-15P or 5-20P plug into a locking L5-20P plug for securing your network device into its outlet.

www.tripplite.com

This one doesn't have this problem.

 

[TheRFMan]

There is one benefit: It's a dedicated circuit. While a standard 5-15 may not offer much greater speed, there's a high chance of tripping the breaker (depending on what other loads are on that circuit).

Good point. Although in most houses I have seen outdoor outlets are also usually dedicated circuits (but I don't think it is required).

 

[fiehlsport]

There is one benefit: It's a dedicated circuit. While a standard 5-15 may not offer much greater speed, there's a high chance of tripping the breaker (depending on what other loads are on that circuit).

Also, it's an L5-20, not a 15, so you can run at 16A @ 120V with the right adapter. You'll only get 12A from a 5-15 household outlet.

 

[TheRFMan]

Also, it's an L5-20, not a 15, so you can run at 16A @ 120V with the right adapter. You'll only get 12A from a 5-15 household outlet.

That's correct, although 5-20 outlets are now common in many houses, especially for garage/outdoor outlets.

 

[Janus]

Also, it's an L5-20, not a 15, so you can run at 16A @ 120V with the right adapter. You'll only get 12A from a 5-15 household outlet.

Ah, sorry, the sentence was not clear. Try this version:

While compared to a standard 5-15, a L5-20 may not offer much greater speed, there's a high chance of tripping the breaker (depending on what other loads are on that circuit).

 

[davewill]

Ah, sorry, the sentence was not clear. Try this version:

While compared to a standard 5-15, a L5-20 may not offer much greater speed, there's a high chance of tripping the breaker (depending on what other loads are on that circuit).

Actually a 120v 20a circuit will give a much bigger boost to charge rate than the difference in rating would suggest because of overhead. A 5-15 outlet gives you 12a@120v or 1440w, 3-400 of which goes to overhead, leaving about 1100w (roughly) going to the battery. The 5-20 outlet gives you 16a@120v or 1920w. Subtracting the overhead leaves you about 1600w going to the battery, a solid 45% improvement. Anything that increases overhead, like cold weather, makes this difference even more pronounced.

Also, I would think there's an excellent chance the pool circuit would be dedicated.