40 amp or 50 amp?

Unclespike102

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Please excuse my use of imprecise terms….

I’m running 220v to the garage - I was going to use and existing 40 amp breaker with 8 gauge wire.

I’d like NOT to buy a $700.00 charging station…will the charging devices Ford provide put 220v into the car?

So, will 40 amps / 8 gauge work? Or is 50 amp / 6 gauge required to work with Ford’s charging devices.?

thank you!
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Davedough

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You need to account for overhead on the circuit. If you are hardwiring, I wouldn't go below a 60amp breaker personally. That's what I installed on mine because I read that that was what was recommended

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You need to account for overhead on the circuit. If you are hardwiring, I wouldn't go below a 60amp breaker personally. That's what I installed on mine because I read that that was what was recommended

1647460898513.webp
By your own chart, a 40A breaker should be fine for the provided 32A Ford Mobile Charger.

You should be fine with 8 gauge, but if you're buying new wire anyway, I'd go for 6 gauge. You'll want a NEMA 14-50 outlet to plug into.

Edit with the disclaimer to always check local electrical code. A 50A breaker with 6 gauge is preferred, but it would be generally acceptable to have a 32A load on 8 gauge wire with a 40A breaker and a 14-50 outlet. Upgrading to 6 gauge is going to do more to future proof you, and I would personally feel more comfortable having a more robust circuit than technically required in this case.
 
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If you're planning to use the Ford Mobile Charger with its 240 Volt plug, then you need to install a NEMA 14-50 outlet. You should never connect a high amperage outlet to a lower amperage wire. The install requires 50 amp wiring and a 50 amp breaker. The breaker is not there to protect your equipment, it's there to protect your wiring and thus your house.

Don't put your entire house at risk because you want to save $50.
 


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Davedough

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By your own chart, a 40A breaker should be fine for the provided 32A Ford Mobile Charger.

You should be fine with 8 gauge, but if you're buying new wire anyway, I'd go for 6 gauge. You'll want a NEMA 14-50 outlet to plug into.

Edit with the disclaimer to always check local electrical code. A 50A breaker with 6 gauge is preferred, but it would be generally acceptable to have a 32A load on 8 gauge wire with a 40A breaker and a 14-50 outlet. Upgrading to 6 gauge is going to do more to future proof you, and I would personally feel more comfortable having a more robust circtuit than technically required in this case.
You're right. I was assuming it was like my ChargePoint and did 48A when hardwired
 

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If you're planning to use the Ford Mobile Charger with its 240 Volt plug, then you need to install a NEMA 14-50 outlet. You should never connect a high amperage outlet to a lower amperage wire. The install requires 50 amp wiring and a 50 amp breaker. The breaker is not there to protect your equipment, it's there to protect your wiring and thus your house.

Don't put your entire house at risk because you want to save $50.
NEC allows the use of a 50A receptacle on a 40A breaker, I see it all the time. Basically since a 40A receptacle doesn’t exist, you are allowed to go one size bigger. This is also why the mobile charger is set to 32A, so it can be used on 40A 14-50 circuits.


Thanks all! 50 amp, 6 gauge it will be.

…and a trip back to return 8gauge / 40 amp….
See above, you are fine doing 8 ga 40A if you don’t want to pay more.
 

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NEC allows the use of a 50A receptacle on a 40A breaker, I see it all the time. Basically since a 40A receptacle doesn’t exist, you are allowed to go one size bigger. This is also why the mobile charger is set to 32A, so it can be used on 40A 14-50 circuits.




See above, you are fine doing 8 ga 40A if you don’t want to pay more.
What happens if you sell your house and the new buyer sees a 14-50 outlet in the garage and plugs in their 40A EVSE?
 

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What happens if you sell your house and the new buyer sees a 14-50 outlet in the garage and plugs in their 40A EVSE?
That’s their fault for not checking the breaker size during installation. You would not be liable since you’re following code.
 
 







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