AGT stops charging at 264 miles

[BS8899]

There are plenty of NEMA 14-15 outlets that are ok, but it’s still always prudent to check as there are a lot of cheap ones that can cause a fire. Many are not designed for the continuous max current load that EV’s demand and it’s a good troubleshooting step.

It’s true we have had a lot of software problems and it’s easy to blame the software. I’m leaning toward @BS8899 Wunderbox theory in this case, with the next step being a service call as the OP is doing.

My PERSONNAL OPINION is, depending on the usage, the paranoia with (cheaper) NEMA 14-50 sockets is somewhat exaggerated.

I am NOT dismissing the concerns with crappy 14-50 sockets per se. My point is it depends on how it is used. Specifically,

>if you keep plugging/unplugging your AC charge adapter from the NEMA 14-50 socket every single time you change your vehicle, then YES, you should pay a premium and get a Hubble or Bryant as they are more robust with their contacts. But do you actually do that?
> the original NEMA 14-50 socket was primarily designed for clothes dryers. Most clothes dryers draw ~30Amps, and they are not unplugged every time you use the dryer (hence, not flexing the contacts).
> For me, I have 3 installations of NEMA 14-50 receptables. Two are Hubble sockets. The other one is Bryant. Both Hubble and Bryant have "beefier" contacts.
> Key is, I seldomly (maybe 1X/year) I'd unplug my charger from the receptacle. I don't think I need to pay $100 for a Hubble receptacle.

I am NOT advising others to just buy the cheap Home Depot NEMA 14-50 sockets for $10. But if you leave your charger plugged in all/most of the time, pick one that is more robust than the $10 "el-cheapo". There are plenty of $30 NEMA sockets with robust contacts.

I am all for safety. But I don't think we need to over-do it and buy the most expensive NEMA 14-50 sockets.

Welcome opinion by others.

 

[socktucker]

There are plenty of NEMA 14-15 outlets that are ok, but it’s still always prudent to check as there are a lot of cheap ones that can cause a fire. Many are not designed for the continuous max current load that EV’s demand and it’s a good troubleshooting step.

It’s true we have had a lot of software problems and it’s easy to blame the software. I’m leaning toward @BS8899 Wunderbox theory in this case, with the next step being a service call as the OP is doing.

I shoulda have clarified I said that with zero authority.

 

[Pragmatic]

The big difference is the dryer uses 30 amps off and on (cycling to maintain temperature) during the 40 minute dry cycle, the car draws 30 amps continuously for hours.

 

[DeaneG]

My PERSONNAL OPINION is, depending on the usage, the paranoia with (cheaper) NEMA 14-50 sockets is somewhat exaggerated....
...Welcome opinion by others.

The problem isn't just plugging and unplugging. It's thermal cycling.
You can find dozens of photos of melted and burned 14-50 receptacles online.
UL is of the "opinion" that receptacles used for EV charging ("continuous duty") should meet a more stringent performance standard than receptacles used for ovens, etc, which do not pull a steady 40 amps for hours on end.

 

[BS8899]

The big difference is the dryer uses 30 amps off and on (cycling to maintain temperature) during the 40 minute dry cycle, the car draws 30 amps continuously for hours.

You are correct about cycling vs a steady state current draw.

That said, as long as the contacts are robust, and can easily carry the current (40/50 Amp), a steady-state current, is less injurius to the contacts than a on/off current (aka dryer) which flexes and fatigue the contacts.

 

[socktucker]

You are correct about cycling vs a steady state current draw.

That said, as long as the contacts are robust, and can easily carry the current (40/50 Amp), a steady-state current, is less injurius to the contacts than a on/off current (aka dryer) which flexes and fatigue the contacts.

My electrician/electrical engineer buddy said the margin of error is really huge in stuff like that and as long as the wire doesn’t start burning it’s probably okay

 

[Adnillien]

You are correct about cycling vs a steady state current draw.

That said, as long as the contacts are robust, and can easily carry the current (40/50 Amp), a steady-state current, is less injurius to the contacts than a on/off current (aka dryer) which flexes and fatigue the contacts.

It really depends on the duty cycle and the thermal rise and fall of the non-steady state current. Comparing a dryer to an EV charger as a load on the NEMA 14-50 outlet, the temperature rise with the EVE charger is much higher than with the dryer. Hence there is more thermal expansion an contraction in outlet for the EV charger versus the dryer. The better outlets have better contact to the supply wires as well as contact to the plug.

 

[Adnillien]

My electrician/electrical engineer buddy said the margin of error is really huge in stuff like that and as long as the wire doesn’t start burning it’s probably okay

Follow your friends advice only if you want to burn your house down. I would not hire him to install an EVSE.

 

[DeaneG]

Just Google "14-50 burned"

 

[BS8899]

My electrician/electrical engineer buddy said the margin of error is really huge in stuff like that and as long as the wire doesn’t start burning it’s probably okay

I was clear in my post I was not advocating for a $10 Home Depot dryer contact. What i was saying:

1) there are plenty of $30 NEMA 14-50 sockets with robust connecting prongs. Educate yourself and pick a good one.
2) don't plug/unplug every time you charge. You do more harm than good.
3) Blindy buying a $100 (e.g., Hubbard) NEMA receptacle is no the the smartest thing to do.
4) when you install high current receptacles, make sure you use the correct gauge of wires AND TORQUE THEM TO THE SPECS!!!
Even a $100 Hubbard NEMA 14-50 receptacle can catch fire if you don't torque the connections correctly!

In summary, know what you are doing. Just paying for a more expensive receptacle without understanding all the dependent pieces won't get you to the right solution.

 

[BS8899]

It really depends on the duty cycle and the thermal rise and fall of the non-steady state current. Comparing a dryer to an EV charger as a load on the NEMA 14-50 outlet, the temperature rise with the EVE charger is much higher than with the dryer. Hence there is more thermal expansion an contraction in outlet for the EV charger versus the dryer. The better outlets have better contact to the supply wires as well as contact to the plug.

Yes, I agree. I am NOT advocating for a cheap NEMA 14-50 socket. That said, just think that you soent $100 on Hubble socket solves the problem is a fallacy.

You need to have the correct gauge of wires ( I always use 1 gauge larger than the rated current) and TORQUE it correctly.

Avoid plugging/unplugging the socket.

 

[DeaneG]

It's easy enough to find a 14-50R that is EV rated. It has an EV graphic on the front. No need to take chances on something that hasn't been proven to meet UL's EV charging specs.

 

[BS8899]

Yes, I agree. I am NOT advocating for a cheap NEMA 14-50 socket. That said, just think that you soent $100 on Hubble socket solves the problem is a fallacy.

You need to have the correct gauge of wires ( I always use 1 gauge larger than the rated current) and TORQUE it correctly.

Avoid plugging/unplugging the socket.

The amount of temperature rise is a function of the wire gauge, the robustness of the contacts, the torque on the wires, etc..

Temperature cycling is the primary cause of loosening of the contact points (wire to receptacle contact prongs, receptacle to plug prongs, etc.). In a dryer cycle, the current is lower, but the number of cycles it a lot higher than an EV charger (which draws a higher but a more steady current).

Therefore, I am not persuaded that a dryer is less stress.

No question that the EV charger draws higher current and needs to use a more robust NEMA 14-50 socket. My point is, simply buying a $100 Hubbard receptacle and consider the problem is solved is optimistic. The wires must be the right gaguge, torqued to the correct spec., etc..

My practice is to i) use 1 gauge larger wires, ii) torque to the correct soec., iii) pick an "over-sized" contact NEMA 14-50 receptacle, not necessarily a $100 Hubbard.

Just don't think a $100 Hubbard alone will solve all your problems. Tryo to understand how to do all the components in the circuit interact.

 

[Pragmatic]

The dryer outlet will never heat up, the load is too intermittent. While the cycling may matter the temperature reached by the dryer receptacle will be too low to ever matter.
The EVSE will heat the receptacle. As it heats the resistance will increase, increasing the power loss and the heat generated. Each long charge will heat stress the connection much more than all the dryer cycling.
In my opinion, plugging and unplugging has a much smaller impact on failure rate operating for long periods of time at high current

 

[Saksak]

[…]

My practice is to i) use 1 gauge larger wires, ii) torque to the correct soec., iii) pick an "over-sized" contact NEMA 14-50 receptacle, not necessarily a $100 Hubbard.

Just don't think a $100 Hubbard alone will solve all your problems. Tryo to understand how to do all the components in the circuit interact.

Those are good practices and good advice. I also had my electrician use one gauge higher and a quality receptacle as cheap insurance against my house burning down.

I don’t think anyone was suggesting the $100 Hubbard, but rather the NEMA 14-50 socket is a good troubleshooting point for EV charging failures and to use quality (EV rated or industrial) sockets with high-quality installations.

 

[BS8899]

The dryer outlet will never heat up, the load is too intermittent. While the cycling may matter the temperature reached by the dryer receptacle will be too low to ever matter.
The EVSE will heat the receptacle. As it heats the resistance will increase, increasing the power loss and the heat generated. Each long charge will heat stress the connection much more than all the dryer cycling.
In my opinion, plugging and unplugging has a much smaller impact on failure rate operating for long periods of time at high current

Plugging/unplugging is a big factor. Notice that evse above 40 Amp are all hardwired, no sockets.

The metal gauge inside a high quality NEMA 14 50 socket is very beefy, MUCH bigger cross section than the wires feed the contacts. The weak link is,the contact area (i.e., plug prongs to the receptacle capture) and plugging/unplugging.

The receptacle metal only heats up because of the contact resistance between the plug pins and the capture forks. Plugging/unplugging loosens the receptacle contacts over time, resulting in heating at the pin/socket interface, which inturn heats up the receptacle. That's why 80amp else are hardwired.

 

[DeaneG]

Plugging/unplugging is a big factor. Notice that evse above 40 Amp are all hardwired, no sockets...
The receptacle metal only heats up because of the contact resistance between the plug pins and the capture forks. Plugging/unplugging loosens the receptacle contacts over time, resulting in heating at the pin/socket interface, which inturn heats up the receptacle....

Residential devices which require a circuit breaker rated at greater than 50 amps are hardwired because the NEC requires it.

I've seen many photos of spec-grade 14-50R where thermal cycling over a period of years loosened the screw connections, causing the rear of the plastic housing to melt and burn. Not all were plugged/unplugged frequently.

Specified screw torque on a spec-grade 14-50R is 25in-lb.
Torque on an industrial/EV-rated 140-50R is 75in-lb, three times higher, and the plastic housing is much beefier with better materials.

Agreed you don't need to spend $100 on a receptacle. Just buy one that's rated by UL for EV use.

 

[Wannabe2026]

Since most like updates:
1. Problem persists. Can’t charge the car at my home.. (. Either 120 or 240)
2. Asked FPL to check power to house, they say good..
3. Tried a neighbor’s charger, level 2. Fine, slow charge, but it worked
4. Went to Lucid Service, they checked our charger. Fine. They put car on charger, fine. They say it’s an issue with our home..
5. Went to another friend’s house, using our charger, their 240 plug, guess what, fine.
So we think it’s our home, but no idea why. Newer house, 6 yo.
Will of course enlist an electrician, but don’t know how to find someone who knows Lucids and charging.

 

[Bobby]

Since most like updates:
1. Problem persists. Can’t charge the car at my home.. (. Either 120 or 240)
2. Asked FPL to check power to house, they say good..
3. Tried a neighbor’s charger, level 2. Fine, slow charge, but it worked
4. Went to Lucid Service, they checked our charger. Fine. They put car on charger, fine. They say it’s an issue with our home..
5. Went to another friend’s house, using our charger, their 240 plug, guess what, fine.
So we think it’s our home, but no idea why. Newer house, 6 yo.
Will of course enlist an electrician, but don’t know how to find someone who knows Lucids and charging.

The wires may be undersized, the connectors to the charger may not be properly torqued or compressed, the breaker might be in need of replacement, the outlet itself might be a cheap residential one where you should go to a commercial one. Check for heat at any of these spots.

 

[socktucker]

Since most like updates:
1. Problem persists. Can’t charge the car at my home.. (. Either 120 or 240)
2. Asked FPL to check power to house, they say good..
3. Tried a neighbor’s charger, level 2. Fine, slow charge, but it worked
4. Went to Lucid Service, they checked our charger. Fine. They put car on charger, fine. They say it’s an issue with our home..
5. Went to another friend’s house, using our charger, their 240 plug, guess what, fine.
So we think it’s our home, but no idea why. Newer house, 6 yo.
Will of course enlist an electrician, but don’t know how to find someone who knows Lucids and charging.

I’d ask an electrician for a second opinion