Chevy Bolt EV Forum banner
  • Hey Guest, welcome to ChevyBolt.org. We encourage you to register to engage in conversations about your Bolt.
1 - 20 of 32 Posts

Registered
Joined
13 Posts
Discussion Starter · #1 ·
I'm taking over a lease on a 2017 Bolt (so total newbie here), and the previous lessee was nice enough to include his level 2 EVSE. Thing is that we have an older home with a 240V 30 amp 3-prong dryer outlet, and the EVSE is 4-prong.

Do any of you know what kind of converter I need? Would this Tesla converter work for a Bolt as well? (Can't post links yet because I'm so new, but on Amazon, it's
called "AC Connectors 1.5FT EVSE 30-Amp 3Prong NEMA 10-30P Dryer Plug to 50-Amp Electric Vehicle Adapter Cord for Tesla Model S [EV1030MS-018]")

Or can I use a Jukebox dryer outlet converter even though the EVSE is a 240v 30 amp box from BSA Electronics?

Other options?
Thanks!
 

Registered
Joined
643 Posts
30 amp dryer plugs are rated for 24 amp continuous load - EVSEs are continuous loads...

The Bolt will draw 32 amps if the EVSE says it will provide it..

You need an EVSE that will only draw 24 amps if you plug it into a 30 amp plug..

The gen 2 Tesla UMC has 30 dryer plug adapters - but you need a J-dapter to Tesla Tap to use a Tesla UMC gen 2 with a Bolt

Tesla Gen 2 UMC is $320
Tesla tap or jdapter is like $250

Or you can buy a 24/30 amp EVSE

Or you can buy an adapter for the Chevy charger that comes with the car and it will do 12 amps.
 

Registered
Joined
643 Posts
It's a plug-in portable EVSE, so I shouldn't have to change the plug, as nothing's really being installed. But I do need a converter to plug it in!
You need to be careful - just converting the plug may lead the EVSE to draw too much power

You haven鈥檛 provided enough info for use to help you.

What is the EVSE and how many amps is it rated?
 

Registered
Joined
746 Posts
Looked thru all the variations of four to three converters, and they all are slightly off, with a price of $112 minimum. Ridiculous. And it appears that the industry is trying very hard to impede that direction. It would be best, if you have no electrician experience, to hire an electrician to put in a 14-50. The extra wire is just another ground, so he should have no problem.
 

Registered
Joined
643 Posts
https://www.bsaelectronics.com/prod...terproof-with-lcd-15ft-bsa-custom-j1772-cable

Some quick google indicates the charger you said you have is a 30 amp charge rated charger - it must be plugged into a 40/50 amp breaker - probably a NEMA 14-50 plug - with proper wiring and proper plug - a 30 amp dryer outlet can only pull 24 amps safely - plugging a 30 amp charger into a 30 amp dryer plug is a safety hazard - the breaker should pop - but if it doesn鈥檛 wire can overheat and/or melt-catch-fire

First rule of EV charging - never charge at a rate that is more than 80% of the breaker...
 

Registered
Joined
643 Posts
50 amp breaker = 40 amp EVSE charge rate - 9,600 watts
40 amp breaker = 32 amp EVSE charge rate - 7,200 watts
30 amp breaker = 24 amp EVSE charge rate - 5,760 watts
20 amp breaker = 16 amp EVSE charge rate - 3,840 watts

The above list is for 240 volt circuits/breaker - for 120 volts the wattage rates will be half.

Watts = Volts * AMPs

Never use more than 80% of the breakers rating for safety - overloading a circuit can lead to fires.
 

Registered
Joined
643 Posts
If your OpenEVSE is a 7.2 kw charger - you will need a 40 amp breaker and corresponding appropriate wiring

Most dryer plugs are 30 amp breakers and wire - a 7.2 KW charger will overload that circuit- causing a safety issue.
 

Registered
Joined
13 Posts
Discussion Starter · #17 ·
50 amp breaker = 40 amp EVSE charge rate - 9,600 watts
40 amp breaker = 32 amp EVSE charge rate - 7,200 watts
30 amp breaker = 24 amp EVSE charge rate - 5,760 watts
20 amp breaker = 16 amp EVSE charge rate - 3,840 watts

The above list is for 240 volt circuits/breaker - for 120 volts the wattage rates will be half.

Watts = Volts * AMPs

Never use more than 80% of the breakers rating for safety - overloading a circuit can lead to fires.
Thanks so much for your help.
There's no way to limit the *car* to drawing only 24 amps through the EVSE, is there?
 

Registered
Joined
643 Posts
Some EVSE are configurable to lower their advertised rate (Tesla UMC gen2 adjusts its charge rate based on which adapter you have plugged in to it)

Most EVSE鈥檚 are not configurable and come fixed at a certain rate that can鈥檛 be changed - Chevy provides no in car adjustments to draw fewer amps than advertised by the EVSE...so if your EVSE says it can do 30 amps the Bolt will pull 30 amps...no way to override

I have no personal experience with OpenEVSE so I don鈥檛 know if it鈥檚 adjustable - it might be.

The point is you have to match the EVSE鈥檚 advertised charge rate to your homes wiring and breaker so the car doesn鈥檛 overload the circuit while charging.

Also it doesn鈥檛 help that EVSE manufactures aren鈥檛 consistent with their terminology - some advertise the charge rate which requires a 125% breaker above charge rate, others advertise the circuit breaker size their require which means their charge rate is 80% of the breaker - you have to read carefully to see which AMP rating any given EVSE is using...its unnecessarily complicated.
 

Registered
Joined
643 Posts
Yes, it is.
If your OpenEVSE is a 30 amp charge rate then that will overload your dryer circuit.

Choices are:

1. See if the OpenEVSE can be adjusted to draw less power to match your dryer plug
2. Upgrade the dryer circuit to a larger breaker 40/50 amp and verify existing wiring is rated for 40 amps continuous loads
3. Install a new 50 amp circuit with appropriate wire - NEMA 14-50 plug
4. Buy a 24 amp charge rate EVSE - 30 amp breaker
5. Buy an adapter for the Chevy Bolt factory EVSE - the Chevy charger only pulls 12 at 12 amps so it could be safely used on a 240 volt 30 amp dryer circuit with apassive adapter

The Bolts maximum charge rate is 32 amps which requires a 40 amp breaker. There are bigger EVSEs than 32 amps - but the Bolt will only pull 32 amps even when plugged into a 40, 48, or 72 amp charger - so bigger chargers are wasted on the Bolt.

The Best plan is to hire a licensed/qualified electrician and install a new circuit near where you park the car so you can charge each night - I recommend a 50 amp circuit are wire with a NEMA 14-50 plug - that will handle virtually any EVSE you can easily find - the is no issue using a lower rated EVSE on a larger breaker.
 
1 - 20 of 32 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top