Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register

30 amp breaker

MorrisonHiker

S 100D 2021.4.12
Mar 8, 2015
9,396
8,543
Colorado
I have a 30 amp breaker for my dryer with a NEMA 14-50 Outlet. How fast will that charge a MY?
Hopefully you have a 14-30 outlet if you have a 30 amp breaker.
30 amps X 240 volts = 7,200 watts, or 7.2 kilowatts (kW). Assuming your Model Y uses about 280 watt hours/mile (like mine), this outlet would charge at about 26 miles of range per hour.
For EVs (continuous load), you can only use 80%, so it would be 24 amps usable, not 30 amps.

A 2021 Model Y LR is rated at 270 Wh/mile: 24 amps * 240 volts / 270 Wh/mile = 21.3 mph.

A 2021 Model Y Performance is rated at 300 Wh/mile: 24 amps * 240 volts / 300 Wh/mile = 19.2 mph.
 

lachambers

Member
May 9, 2020
166
45
Lighthouse Point Florida
Hopefully you have a 14-30 outlet if you have a 30 amp breaker.

For EVs (continuous load), you can only use 80%, so it would be 24 amps usable, not 30 amps.

A 2021 Model Y LR is rated at 270 Wh/mile: 24 amps * 240 volts / 270 Wh/mile = 21.3 mph.

A 2021 Model Y Performance is rated at 300 Wh/mile: 24 amps * 240 volts / 300 Wh/mile = 19.2 mph.
Thank you morrisonHiker
 

MD-2000

Member
May 1, 2019
537
359
Winnipeg
Yes - a portable charger with the 14-50 will try to draw 32A. (it's max capable). that should pop the breaker. Get a 14-30 plug for your portable charger, or on your car's charging options limit it to 24A. (And check that regularly to be sure the car has not decided to reset itself...) But only as a stop-gap. Get the correct plug and it will limit the charger's draw.

Electrical code says "DO NOT DRAW MORE THAN 80% OF RATED CIRCUIT/BREAKER AS A CONTINUOUS LOAD" As MorrisonHiker says.

I have a Gen2 charger and got a 50A cord 14-50 from Amazon, so I could plug it in instead of hard wiring. But the Gen2 Wall Charger has a dial to set max current limit.
 

About Us

Formed in 2006, Tesla Motors Club (TMC) was the first independent online Tesla community. Today it remains the largest and most dynamic community of Tesla enthusiasts. Learn more.

Do you value your experience at TMC? Consider becoming a Supporting Member of Tesla Motors Club. As a thank you for your contribution, you'll get nearly no ads in the Community and Groups sections. Additional perks are available depending on the level of contribution. Please visit the Account Upgrades page for more details.


SUPPORT TMC
Top