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[Motoproponent]

Like if you have two bikes that each max out at 3kw AC Charging, could a splitter be cobbled together to allow them both to charge from a single 6kw J-plug?

I'm finding on road trips with multiple bikes, there is a conundrum where there is only on spot to plug in for the night. We both want to get a full charge but that means someone has to wake up in the middle of the night and move the plug from one bike to another. If the plug can push 6kw but we're each only going to use half of that...?!?!

Imagine the bikes in question are DCFC capable bikes with relatively small and low power OBC, like a couple of Energicas or an Energica and a Livewire One.

[hotsauce]

Yes it's possble.
https://www.tindie.com/products/nsayer/j1772-hydra/
There's a fair bit of DIY involved, but I can see where it would be handy

[TheRan]

That seems needlessly complicated for what Motoproponent wants to achieve. Seeing as it's just a single phase AC output I would assume you could split it like you would a main output at your home.

[Specter]

why don't you just get a 240 volt extension cord like they make for generators that has 2 heads on it?
Plug the plug into the wall and then each charger into it's respective head  pulling 15 amps each for a total of 30 amps and both bikes are charging at the same time.

The charger is going to want to talk to the bike when charging, so you can't parallel / split that part.

Of course you are going to have to get the head that adapts to YOUR plug but here's a sample of what I am talking about.

https://www.ebay.com/itm/226346509858

Aaron

Edit:  if you are talking about using someone elses J charging station,  they make boxes, pre made that do this as well.  You plug the charger into the box and the box has 2 cords to split the power between the vehicles.  It's not exactly cheap though.

[TheRan]

There isn't actual communication right, as in data sent from the vehicle to the "charger"? My understanding is there's just a signal telling the station that something is plugged in, achieved with a certain resistance across certain pins or something like that. I have a Mennekes to UK mains socket adapter which obviously doesn't communicated with whatever device is plugged into that mains sockets.

[Motoproponent]

why don't you just get a 240 volt extension cord like they make for generators that has 2 heads on it?

The use case would be at a hotel with a Clipper Creek J-plug or Destination charger that's hardwired.

I have a J1772 to NEMA 5-20. In theory I could plug a power strip capable or 240 volt output into it and then plug the two EVSE into that. I have all those pieces so I could try it sometime but I was hoping for a more elegant solution.

Since this happens so infrequently I may just have to come to grips with my inner Florida man and embrace the jank.

There isn't actual communication right, as in data sent from the vehicle to the "charger"?

The J1772 standard has a little bit more than that. It uses resistance to signal that something is attached, the locking mechanism is secure and whether or not the receiving vehicle has vented batteries. Redditors have pointed out the danger if one vehicle on the splitter get disconnected the other vehicle attached would keep the free end "live" and could potentially cause some manner of calamity.

I think this idea should die on the vine.

[TheRan]

But, you're not sharing the charger with some stranger who's going to unplug their vehicle and leave. I'm presuming you and your buddy will just wait to both unplug at the same time.

[SwampNut]

It's always hilarious to me to hear words like "I assume" and all manner of carelessness when discussing 240v power.  The J connection uses PWM signaling in both directions to communicate both the demand and the supply ability, and agree on a setting.  There's more than just some simple resistance.  You certainly can't have both bikes "talking" to the EVSE.

The connector is not powered until the above finishes.  So you don't have arcs when you plug in, people can't be electrocuted, etc.  In a simple cobbled-together splitter, one side would stay live after negotiation, but can't negotiate at all itself.

Applying input power to a J plug should NOT initiate charging without the communication.  I haven't tried it yet, I should.  But if the bikes meet standards, one will not charge.

I recently learned that one of my EVSEs won't stay on its 16a setting and reverts to the full 24a under certain circumstances.  So there are even those quirks.  Also although I successfully rigged my generator to work with an EV, it won't charge the Zero.  That tries to take full power instantly, the generator can't speed up fast enough, and it stops.  Repeat.  The Rivian is fine because it ramps up power.  So I need a switchable load if I want to do it (which I don't, it was a test).

[Specter]

swampnut, I assume you are charging your bike on the generator using the J plug?

to get around that,  tell it to charge at 5 amps or 3 amps or some light load,  it starts, your generator catches up, then flip the lever on the bike to walk the charge rate up to the 15 amps.  or if you are doing DC,  bring it down to  5 /10 amps and walk it up the same way.

This way you don't bog the gen, and potentially kick the charger out due to a power quality issue, if you have a charger that looks at that, or you just lug your gen into the ground.

Aaron

[Motoproponent]

to get around that,  tell it to charge at 5 amps or 3 amps or some light load, 

Can Zeros change the charge current like Energicas can?

[Specter]

swampnut I don't know your skill level with electric or ability to  jury rig crap to do what you need it to.

with that,  plug your dryer into the generator turn it on, there the generator is running, is caught up and the governor is stroked for the load of your dryer  that is about 6kw.  and should be at your 60 hz.  Now plug the bike in,  the second the bike kicks in and it starts bogging, flip the braker for the dryer, now the 'already loaded' generator essentially just shifts its power stroke from the dryer to the waiting bike.  It's already loaded up and governor set for that load, it should go without too big a hitch.

I used to have to hot shot diesel generators in the navy with crap like this,  or little cutesies like lifting compression,  get the thing spinning then slamming it down to hopefully catch a pop or two and take off ..  if that didn't work, then we'd have to light fires off the back wall of the boiler, and THAT was just plain not fun...

If you are not comfortable playing with wattage like that then dont. but just an idea.

Aaron

[TheRan]

It's always hilarious to me to hear words like "I assume" and all manner of carelessness when discussing 240v power.  The J connection uses PWM signaling in both directions to communicate both the demand and the supply ability, and agree on a setting.  There's more than just some simple resistance.  You certainly can't have both bikes "talking" to the EVSE.

The connector is not powered until the above finishes.  So you don't have arcs when you plug in, people can't be electrocuted, etc.  In a simple cobbled-together splitter, one side would stay live after negotiation, but can't negotiate at all itself.

Well apparently Mennekes uses the same signalling and I have a simple adapter that converts Mennekes to a regular mains outlet. There's no communication going through that outlet to my bike so whatever is telling the EVSE to put out power is inside the adapter.