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EVDRIVER
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Re: 50 Amp Line to use supplied 240 cord on 2018?

Wed Sep 19, 2018 2:38 pm

Newporttom wrote:All I know about electricity is not to lick my fingers and stick them in a socket.... But I think I figured out from reading the thread, that the second number on the plug means the amps. So a 14-50 means a 50 amp line.



That's a common post installation technique for testing the outlet. (that's a joke)

powersurge
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Re: 50 Amp Line to use supplied 240 cord on 2018?

Thu Sep 20, 2018 7:06 am

The 2018 is a Leaf like any other... You don't need to change the setup you had for you old one>>>>>..... Unless you were using a slower EVSE (like a 16-20 amp charger).

For home use, the fastest charger is the 30 amp EVSE which charges at 6.6 kwh.... Since that one uses 30 amps, you may want to install a 40 amp breaker to protect the wiring ... At this point in technology, no one needs a 50 amp breaker because there is no 40 amp evse or car that can handle more than the 6.6 kwh charge...

WetEV
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Re: 50 Amp Line to use supplied 240 cord on 2018?

Thu Sep 20, 2018 9:21 am

powersurge wrote:car that can handle more than the 6.6 kwh charge...


Lots of cars can handle more that 6.6kW charging rate. Perhaps you mean no LEAFs can...
WetEV
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Most everything around here is wet during the rainy season. And the rainy season is long.
2012 Leaf SL Red (Totaled)
2014 Leaf SL Red

powersurge
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Re: 50 Amp Line to use supplied 240 cord on 2018?

Thu Sep 20, 2018 10:58 am

WetEV wrote:
powersurge wrote:car that can handle more than the 6.6 kwh charge...


Lots of cars can handle more that 6.6kW charging rate. Perhaps you mean no LEAFs can...


What car? Forget about Tesla...

cwerdna
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Re: 50 Amp Line to use supplied 240 cord on 2018?

Thu Sep 20, 2018 11:52 am

powersurge wrote:
WetEV wrote:
powersurge wrote:car that can handle more than the 6.6 kwh charge...


Lots of cars can handle more that 6.6kW charging rate. Perhaps you mean no LEAFs can...


What car? Forget about Tesla...

Off the top of my head, besides Tesla-powered vehicles like gen 2 Rav4 EV and Mercedes B-Class ED, these US-market non-Tesla-powered vehicles have OBCs above 6.6 kW: BMW i3, Chevy Bolt and '19 Chevy Bolt (optional) and I think VW e-Golf. This is probably not a complete list.

'13 Leaf SV w/premium package (owned)
'13 Leaf SV w/QC + LED & premium packages (lease over, car returned)
'06 Prius

Please don't PM me with Leaf questions. Just post in the topic that seems most appropriate.

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EVDRIVER
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Re: 50 Amp Line to use supplied 240 cord on 2018?

Thu Sep 20, 2018 1:29 pm

powersurge wrote:The 2018 is a Leaf like any other... You don't need to change the setup you had for you old one>>>>>..... Unless you were using a slower EVSE (like a 16-20 amp charger).

For home use, the fastest charger is the 30 amp EVSE which charges at 6.6 kwh.... Since that one uses 30 amps, you may want to install a 40 amp breaker to protect the wiring ... At this point in technology, no one needs a 50 amp breaker because there is no 40 amp evse or car that can handle more than the 6.6 kwh charge...



You mean no Nissan. It is very common for people to move and have a Tesla plugged into a 14-50. That means you are drawing 40A on a 40A breaker which is more than the 80% rule. Since most 40A breakers are not rated for continuous use as the connectors on that type of breaker are designed so they do not come loose. Ones that do then create high resistance and then potential big issues. I have seen this heat related failure on more than one overloaded breaker.

wwhitney
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Re: 50 Amp Line to use supplied 240 cord on 2018?

Thu Sep 20, 2018 2:13 pm

EVDRIVER wrote: It is very common for people to move and have a Tesla plugged into a 14-50. That means you are drawing 40A on a 40A breaker which is more than the 80% rule. Since most 40A breakers are not rated for continuous use as the connectors on that type of breaker are designed so they do not come loose. Ones that do then create high resistance and then potential big issues. I have seen this heat related failure on more than one overloaded breaker.

To clarify this, there are two separate issues with using a 40A breaker at 40A continuously:

1) With a 40A continuous load, all the connections in the circuit are going to be put to the test. Any poor connections are going to quickly develop hot spots, and if not caught could start a fire. The same is true of a 32A continuous load on the circuit, but only 64% as much power would be dissipated at the poor connections. That would still be enough to cause most poor connections to show up, but obviously there could be a marginal connection that survives 32A but not 40A.

2) For a 40A breaker in the worst case environment (40C ambient temperature, in a panel full of other breakers), the thermal trip is only designed to hold at 32A continuously (80%). If the continuous current exceeds 32A, the thermal trip mechanism may trip. That thermal trip mechanism is the only part of the circuit that is not rated for 40A continuous.

Because of (2), when installing a 40A continuous load, it is necessary to specify a 50A breaker. And because the wiring needs to be adequately protected by the breaker, the wiring needs to be rated at 50A. The result will be a circuit in which everything is rated for 50A continuously, except the thermal trip rating of the breaker, which will be rated to hold at 40A continuous.

It is a poor product design choice that the Tesla Mobile Connector doesn't offer an option to plug into a 14-50 receptacle while restricting the EVSE current to the 32A maximum suitable for a 40A circuit.

Cheers, Wayne

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Re: 50 Amp Line to use supplied 240 cord on 2018?

Thu Sep 20, 2018 3:03 pm

wwhitney wrote:
EVDRIVER wrote: It is very common for people to move and have a Tesla plugged into a 14-50. That means you are drawing 40A on a 40A breaker which is more than the 80% rule. Since most 40A breakers are not rated for continuous use as the connectors on that type of breaker are designed so they do not come loose. Ones that do then create high resistance and then potential big issues. I have seen this heat related failure on more than one overloaded breaker.

To clarify this, there are two separate issues with using a 40A breaker at 40A continuously:

1) With a 40A continuous load, all the connections in the circuit are going to be put to the test. Any poor connections are going to quickly develop hot spots, and if not caught could start a fire. The same is true of a 32A continuous load on the circuit, but only 64% as much power would be dissipated at the poor connections. That would still be enough to cause most poor connections to show up, but obviously there could be a marginal connection that survives 32A but not 40A.

2) For a 40A breaker in the worst case environment (40C ambient temperature, in a panel full of other breakers), the thermal trip is only designed to hold at 32A continuously (80%). If the continuous current exceeds 32A, the thermal trip mechanism may trip. That thermal trip mechanism is the only part of the circuit that is not rated for 40A continuous.

Because of (2), when installing a 40A continuous load, it is necessary to specify a 50A breaker. And because the wiring needs to be adequately protected by the breaker, the wiring needs to be rated at 50A. The result will be a circuit in which everything is rated for 50A continuously, except the thermal trip rating of the breaker, which will be rated to hold at 40A continuous.

It is a poor product design choice that the Tesla Mobile Connector doesn't offer an option to plug into a 14-50 receptacle while restricting the EVSE current to the 32A maximum suitable for a 40A circuit.

Cheers, Wayne



The hard wired units do but not the mobile connector. You also make a point that some here can't seem to embrace. Often people install a 40A circuit on a 14-50 because they may have a load at 32A. However they may sell the house or get a Tesla and plug in a 40A unit because the "outlet works". This is the exact reason all outlets really should have the circuit to match not to mention the added safety factor for a 32A device. Heating and cooling on breakers with high loads can lead to big issues. I'm not clear on why people recommend the lowest requirement solution when it comes to safety. This is exactly the reason some cities are enforcing stricter requirements on EVSE outlets.

SageBrush
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Re: 50 Amp Line to use supplied 240 cord on 2018?

Thu Sep 20, 2018 4:00 pm

EVDRIVER wrote: It is very common for people to move and have a Tesla plugged into a 14-50.


My Tesla Model 3 LR mobile EVSE has a 14-50 plug but cannot pull more than 32 Amps. The car OBC is rated for up to 48 Amps.
Tesla sells plug adapters for its EVSE to use a variety of outlets. The adapter must be setting the EVSE to a lower Amp draw. I don't know if Nissan has something similar for lower amperage L2 (240v) outlets.
Alternatively, can either the Nissan LEAF or the mobile EVSE be configured to draw a lower amperage ? If so and OP is happy with that charging rate, he could consider buying a generic adapter to e.g. a 6-30 plug and perhaps not incur the cost to upgrade the outlet.

----
This thread has become a religious fight, so I'll throw in my oar and say that the safest approach is to have a 50 Amp circuit and breaker behind a 14-50 outlet.

I am not an electrician.
Last edited by SageBrush on Thu Sep 20, 2018 4:57 pm, edited 6 times in total.
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Bought off-lease Jan 2017 from N. California
Car is now enjoying an easy life in Colorado
3/2018: 58 Ahr, 28k miles
-----
2018 Tesla Model 3 LR, Delivered 6/2018

webfootguy
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Re: 50 Amp Line to use supplied 240 cord on 2018?

Thu Sep 20, 2018 4:04 pm

Just to add some more details, the Tesla Mobile charger supplied with S/X/3 is a Gen 2 charger that limits the charge rate to 240v/32 amps, but the older Gen 1 chargers were able to supply 240v/40 amps.

Phil
2016 SL with Premium Package 3 year lease on 03-25-2016.

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