Chevy Bolt EV Forum banner

1 - 14 of 14 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter #1
So I have a J1772 plug, a roll of #10awg 4 conductor wire and an old 30Amp 240v laundry outlet... Can I run power straight from the 30A to the car? Is the EV cordset required? 2018 Bolt - I understand that the cordset that came with the car is capable of taking the 240v directly but I’m not a fan of my much better half inadvertently plugging a hair dryer Into an adapter I make up...
 

·
Registered
Joined
·
1,902 Posts
... adding, the EVSE tells the charger in the car how much power to draw. Even if you were able to replicate the signal, would your car draw 32A (way beyond 80% of 30A), thus overheating the wire and burning down the house? Not worth it. Better off buying a plug adapter and run your OEM EVSE at 240V 12A. Or if you want faster charge, there are 16A and 24A EVSEs for $200-300 on Amazon and eBay.


 

·
Registered
Joined
·
3,603 Posts
An extra 7% over 10 AWG rating probably isn't going to burn anything down, though I'm not recommending it. You can specify a lower amperage anyhow because it's a simple resistor value that communicates the supply capability.

I'm pretty willing to cobble together my own solutions to things, but I've never heard of someone doing this, and it's beyond my comfort level (which is very comfortable).
 

·
Registered
Joined
·
1,902 Posts
Sure, only be concerned with wiring outside the wall.
 

·
Registered
Joined
·
3,289 Posts
I understand that the cordset that came with the car is capable of taking the 240v directly but I’m not a fan of my much better half inadvertently plugging a hair dryer Into an adapter I make up...
I'm using the charge cord that came with the car on 240V. I built an adapter using 10 gauge wire to connect to the 240V outlet. A plug and receptacle from home depot. You could buy a clam shell device to install over the 5-15 connectors. Lock tie the device in place. Should discourage its use.
 

·
Registered
Joined
·
445 Posts
An extra 7% over 10 AWG rating probably isn't going to burn anything down, though I'm not recommending it. You can specify a lower amperage anyhow because it's a simple resistor value that communicates the supply capability.
This is not how the control pilot operates. The EVSE sends a +/- 12V square wave over the control pilot line. The duty cycle of the signal determines the available current. There is a resistor system between the EVSE and the EV along with a connectivity diode. This system is used by the EV to signal the state of the connection to the EVSE.

To the OP, you are not going to be able to get away without an EVSE. It's a safety device designed to make sure that someone won't get electricuted in wet conditions and to ensure that the EV doesn't draw more power than either the circuit or the EVSE can handle.

ga2500ev
 

·
Registered
2020 Bolt
Joined
·
41 Posts
You absolutely MUST have an EVSE. If you want to do it yourself check out OpenEVSE they sell kits from which you can make one - I've never used them myself but they've been aroung for quite a while. You can wire up - or buy - a 240 plug to 120 socket. If you do this, paint or plasti-dip it red and put a durable warning tag on it. Keep it with the car or the OEM EVSE and nobody will get hurt. I admire your DIY spirit but some things are best left to the pros.
 

·
Registered
Joined
·
44 Posts
I think it bears asking: is your much better half apt to be using a hair dryer outside or in the laundry room? By all means, add labels and whatnot to make it clear the adapter is not for anything but the EVSE, but in practice this really shouldn't be an issue that is likely to arise.

Either way it doesn't matter. Electric vehicles have all sorts of safety mechanisms in place to prevent, among other things, someone from doing exactly this. Without the control signal the vehicle will refuse to close the circuit and draw power.
 

·
Registered
Joined
·
440 Posts
So I have a J1772 plug, a roll of #10awg 4 conductor wire and an old 30Amp 240v laundry outlet... Can I run power straight from the 30A to the car? Is the EV cordset required? 2018 Bolt - I understand that the cordset that came with the car is capable of taking the 240v directly but I’m not a fan of my much better half inadvertently plugging a hair dryer Into an adapter I make up...
Buy this from QuickCharge Power if you don't want to make your own:
My240 Adapter
 

·
Registered
Joined
·
55 Posts
An extra 7% over 10 AWG rating probably isn't going to burn anything down, though I'm not recommending it
It's not 7% over, its 27% over. When using an electrical component such as a wire or outlet under continuous high load such as for EV charging, you are supposed to down-rate components to 80% of their rated value. So something rated for 30 Amps should be down-rated to 24 Amps.
 

·
Registered
Joined
·
42 Posts
I charge my Bolt from a 30 amp dryer outlet. Ran a semi permanent extension from the receptacle to the location where I installed my JuiceBox. The Juicebox lets you set the input current so you don't pop the circuit breaker. The Bolt will draw up to 32 amps. When designing circuits NEC says to load them at 80%. However, you can draw up to 30 amps as long as the circuit breaker doesn't pop you are fine. I configured the JuiceBox to run at 27 amps. Tried it up to 30 and didn't blow the circuit breaker but why push it. I like a 10% headroom. Impossible to find a 10 AWG extension with the proper connectors so I made my own using 10 gauge wires bought everything on-line. I rent and didn't want to invest on 40 amp circuit and am happy with how it worked out.
 

·
Registered
Joined
·
74 Posts
For a second charging location I bought a 30amp selector and built a switch that supplies either my EVSE or dryer.
I purchased an OpenEVSE kit primarily because I needed a 35ft J1772 and couldn't find one on a pre-assembled system. It wasn't a cheap solution but I got tired of dragging my Tesla MU 2 back and forth. Works great.
And yes, I know the EVSE isn't a "charger" but my house guests may not understand the distinction......
30amp switch.jpg
 
1 - 14 of 14 Posts
Top