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EV charger plug for RV?

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justinm001

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I'm rebuilding my power plugs and trying to find info on how the EV L2 chargers work and if there's a possibility to add a pair of J1772 plugs for charging my Lithium banks as well as a J1772 outlet for charging EV vehicle from my RV.

I believe the J1772 requires some handshake and isn't just a 240V outlet which makes things complicated and I don't see much of any info on how to pull power from a L2 charger.

Why.... Because I see a lot of EV charging stations coming around and it would be a great asset when boondocking to pull up to a L2 charging station and fill up while grabbing dinner then head back out. Also quite a few places have free EV charging stations so I could charge up at night when the business is closed and not block a bunch of spots. Also if I'm going to run a 50amp wire at my home might as well put an L2 Ev charger then just use for the RV

Why an outlet? Because if im boondocking and have excess solar I can use it to charge an EV toad and if the EV has bidirectional charging then I just extended my battery bank 100KwH or so.
 
justinm001 said:
I'm rebuilding my power plugs and trying to find info on how the EV L2 chargers work and if there's a possibility to add a pair of J1772 plugs for charging my Lithium banks as well as a J1772 outlet for charging EV vehicle from my RV.

I believe the J1772 requires some handshake and isn't just a 240V outlet which makes things complicated and I don't see much of any info on how to pull power from a L2 charger.

Why.... Because I see a lot of EV charging stations coming around and it would be a great asset when boondocking to pull up to a L2 charging station and fill up while grabbing dinner then head back out. Also quite a few places have free EV charging stations so I could charge up at night when the business is closed and not block a bunch of spots. Also if I'm going to run a 50amp wire at my home might as well put an L2 Ev charger then just use for the RV

Why an outlet? Because if im boondocking and have excess solar I can use it to charge an EV toad and if the EV has bidirectional charging then I just extended my battery bank 100KwH or so.
Click to expand...
L2 EV chargers are just a 240V outlet...
The charger to DC is in your car...

To use an EV charger on the road to charge your house bank, you would need a controller that takes the 400 to 800V DC and converts it down to battery charge voltage... 12 or whatever your house bank voltage.
You would THEN need a connection with communication circuitry to talk to the fast charger, so it knows what voltage to send your way...
 
Supervstech said:
L2 EV chargers are just a 240V outlet...
The charger to DC is in your car...

To use an EV charger on the road to charge your house bank, you would need a controller that takes the 400 to 800V DC and converts it down to battery charge voltage... 12 or whatever your house bank voltage.
You would THEN need a connection with communication circuitry to talk to the fast charger, so it knows what voltage to send your way...
Click to expand...
The 400 and 800V DC are L3 chargers and not everything supports that so I'm only talking L2 chargers. These are just 240V up to 80amps I believe.

the problem isn't the power its getting the device to output power and I'm not seeing any J1772 car side chargers or how they work. My understanding is its 5 wires and part of it is communication where the car side tells the other side what it can accept, then handshakes and it'll turn on the flow. I can't just plug in and get the 240v power. I'm not sure if this is something I can buy and setup or have to pull off an old EV junk car and reconfigure. Most EVs are high voltage 350-400V so I can't easily just pull off and use their charger.

So basically I'm asking if anyone knows of a J1772 car side charger?
 
justinm001 said:
The 400 and 800V DC are L3 chargers and not everything supports that so I'm only talking L2 chargers. These are just 240V up to 80amps I believe.

the problem isn't the power its getting the device to output power and I'm not seeing any J1772 car side chargers or how they work. My understanding is its 5 wires and part of it is communication where the car side tells the other side what it can accept, then handshakes and it'll turn on the flow. I can't just plug in and get the 240v power. I'm not sure if this is something I can buy and setup or have to pull off an old EV junk car and reconfigure. Most EVs are high voltage 350-400V so I can't easily just pull off and use their charger.

So basically I'm asking if anyone knows of a J1772 car side charger?
Click to expand...
Lots of youtube vids and threads here I think about the resistors needed to get the outlet to produce 240V...
 
rustythorn said:
i think you need some kind of signal/handshake to get the public charging station to start flowing current, hence, what i put in post #8
Click to expand...

Yeah, there's definitely some sort of "communication". I assume (not always wise I know) that this would be included in the adapter.

I've asked the seller, let's see if there's a response.

EDIT Sadly the response was one word, "no", which sort of negates the whole point of having the beast.
 
Last edited:
justinm001 said:
I believe the J1772 requires some handshake and isn't just a 240V outlet which makes things complicated and I don't see much of any info on how to pull power from a L2 charger.
Click to expand...
It easy. You can build a circuit with few resistors and a switch. Look at j1772 control pilot.
Or a super easy solution is to buy a J1772 Active Vehicle Control Module.
as well as a J1772 outlet for charging EV vehicle from my RV
Click to expand...
No! The best to charge an EV from your battery is to have a 240VAC outlet to plug an EVSE.
 
I did one recently for a 51V system. It was totally custom.. and wasn't really cheap. It required a couple of special chargers that run in parallel. Together they charge about as fast as the alternator - around 6kW. Works great in the the southern heat and keeps me from having to drive for a couple of hours just to recharge. My build doesn't honor the duty cycle from an EVSE, but any 6.6kW pedestal that's not 'shared' (most of them) has worked without issues. I used a J1772 extension cord for the outlet that unfortunately didn't carry the proximity pin through it, so I had to implement a switch inside to reduce the chance of it getting disconnected while under load. You won't find anything off the shelf that does bidirectional at these kWs unless you steal it from one of the few vehicles that currently has it. Careful with all those adapters - on your typical L2 charger the voltage is always going to be split phase 208-240V and there's never a neutral. Those adapter cables that go to a NEMA5-15 receptacles will fry anything that's not rated for dual voltage. If you put any current to the ground pin on a J1772, then the EVSE should shut it down. Your dual inverter system would probably ground fault an EVSE if you tried to connect it, as the two units will never operate in perfect balance leading to current on the neutral which would then be bonded to the ground. Good luck parking a full sized RV near an EV charger though - it can be a challenge sometimes with my van.

rv_ev_charging_port.PNG
 
yabert said:
It easy. You can build a circuit with few resistors and a switch. Look at j1772 control pilot.
Or a super easy solution is to buy a J1772 Active Vehicle Control Module.
Click to expand...
You also need to be able to limit charge current to what the EVSE can provide. Not sure what the "easy" solution there is.
 
Shimmy said:
You also need to be able to limit charge current to what the EVSE can provide. Not sure what the "easy" solution there is.
Click to expand...
Yes, this is only true if you have a powerful charger (more than 6 kW) as most EVSE can give 30A or more.
Personally, I've use a 12 kW charger on many EVSE and the key was to adjust the charger power based on the EVSE.
 
Shimmy said:
You also need to be able to limit charge current to what the EVSE can provide. Not sure what the "easy" solution there is.
Click to expand...
There are CAN enabled chargers that can take direction from an EVCC which would read the duty cycle on the pilot pin. The easiest off the shelf way to do this when I researched it was from thunderstruck motors. The most common chargers are nominal 2500W, but the 2500W units built for 48V charging appear to max out at 35A, so really like 1800W per parallel charger. It'd be expensive to go over 6kW, and a majority of the pedestals I see just go to 6.6kW. I personally went with dual meanwell DBU-3200 chargers that are software set in output (could be modified via serial programming). 2 parallel 3200W 48V units push around 105A (5% derated for parallel operation). So considering 51.2 nominal voltage, these would pump out more like 2600W per unit compared to 1800W.
 
Supervstech said:
To use an EV charger on the road to charge your house bank, you would need a controller that takes the 400 to 800V DC and converts it down to battery charge voltage... 12 or whatever your house bank voltage.
You would THEN need a connection with communication circuitry to talk to the fast charger, so it knows what voltage to send your way...
Click to expand...
afaik L3 DC charger would be reasonably "easy" as they adjust themselves according to load and can supply 50v to 400v or 50v to 800v+.

16S lifepo4 could be close enough to be charged from 50 to 400V DC charger at 500A :whistle:
Anything from 5A to 500A can be requested by the PLC pilot signal from the EVSE.
There seem to be couple of DIY options for the PLC signaling:

BMW I3 Fast Charging LIM Module - openinverter.org wiki

openinverter.org openinverter.org

CCS EVCC using AR7420 - openinverter.org wiki

openinverter.org openinverter.org

This if anything would belong under the "Danger zone" forum section.
 
Hello everyone. This is the closest/most recent thread to get advise regarding the process that I'm doing which is very similar to this...
Rudimentary flow chart:
Level 2 EV charge station >
-J1772 TO NEMA 6-50 ADAPTER >
- NEMA 6-50p to L14-30r ADAPTER >
- NEMA L14-30P PB30 Power Inlet Box, 125/250 Volt >
- 240v AC input of a 48v 6000w mpp that has a 6000w inverter to power the box truck as it charges the
- 48v 5.3Kwh LiFePO4 solar battery.
I'm also going to be able to charge said LiFePO4 with a regular 120vAC LiFePO4 48v charger (longer charge time) when a station isn't easily accessible (25ft long total vehicle length), I'm also contemplating a 12vDC to 48vDC charger for when I'm driving as I've already upgraded to the strongest alternator available for the engine.
I know it seems like overkill, but the heater in the winter (1500w 120vAC) and the air conditioner in the summer (1800w 120vAC) require greater power to run 24hr a day as needed than my 5.3Kwh battery will power on its own, and these options are less expensive than the $2,400 solar panels package I'm hoping to install once the funding for the project becomes available.
Any thoughts, comments or ideas would be great
Thank you everyone ?
 
justinm001 said:
The 400 and 800V DC are L3 chargers and not everything supports that so I'm only talking L2 chargers. These are just 240V up to 80amps I believe.

the problem isn't the power its getting the device to output power and I'm not seeing any J1772 car side chargers or how they work. My understanding is its 5 wires and part of it is communication where the car side tells the other side what it can accept, then handshakes and it'll turn on the flow. I can't just plug in and get the 240v power. I'm not sure if this is something I can buy and setup or have to pull off an old EV junk car and reconfigure. Most EVs are high voltage 350-400V so I can't easily just pull off and use their charger.

So basically I'm asking if anyone knows of a J1772 car side charger?
Click to expand...
It may cost a little more than AliExpress but it's warranty available sooner as well

J1772 to NEMA 6-50 Adapter – EVSE Adapters

www.evseadapters.com www.evseadapters.com
Description: (emphasis added by my)
J1772 to NEMA 6-50 adapter makes it easy to plug in and use your welder, or any appliance that has a NEMA 6-50 plug, at all public J1772 charging stations.

["""This adapter works by using a specially designed circuit inside the plug that basically tricks the charging station into thinking a vehicle is connected and ready to charge."""]

This adapter is rated for 50 amps maximum, or 40 amps continuous, but please make sure that the charging station can deliver the amperage your application requires.
Most public charging stations can support 30 amps or more, and usually have their power rating marked on a label affixed to the unit.
This adapter features a J1772 inlet and a NEMA 6-50 receptacle, rated for 50 amps at 250V AC.
Weather-resistant and suitable for outdoor use.
 
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