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Discussion Starter · #1 ·
Anyone using two juice boxes paired for load sharing? I read the load sharing article they have of their site and it indicates to me that in the event of loss of internet the units will default back to 8 amp service until the connection can be restored. I wrote their tech support email people today and asked if the units communicated directly with each other or via their website. They told me via the website and if the internet was down the two units would default to 1/2 the max. I wrote them back for clarification, but no answer.

So I got conflicting answers:
1) when loss of internet the units default to a fair / even fraction of the max power
Or
2) when loss of internet the units default to 8 amps until internet restored and they can sort out which one needs power.

So I thought I’d ask here to see if anyone could straighten me out.

Here’s my purpose... I have a Bolt and my wife just got a used Tesla Model S. So now I’m in a position to share a 50 amp power feed in the garage with two EVSEs. My option is juice box and use the Tesla J1772 adapter to make it work with the Tesla, OR get two Tesla branded wall chargers and cut the Tesla plug off one of them for use on the Bolt.

The Tesla wall chargers communicate via a local serial link, so (unlike the juice box) if the internet is down, they work out load sharing.

I’m really tempted to go with the Tesla wall chargers and replace one of those plugs with J1772. At least that way my wife would have a button on the plug to press to open the charge bay door.

So how about it Juice box fans!!!
 

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If you really need to charge both cars at the same time I'd probably go with the Tesla wall chargers but instead of replacing the Tesla proprietary connector on the second charger with a J1772 I'd probably use a TeslaTap or similar device to allow me to plug in my unmodified Tesla charger to the Bolt. That way if you get a second Tesla later you are already good to go and for the Bolt you have the added benefit of the TeslaTap and the ability to charge from other Tesla chargers.
 

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I'm kinda' in the same situation...sans the wife's Tesla, but two EV's and one Juicebox Pro 40.

I talked to Juicebox last year about this, and the engineer showed me a particular wiring diagram to have 2 outlets on the same circuit. I showed it to my [licensed] electrician and he declined to do it. And like yourself, when I called back for clarification (after Juicebox was acquired), I couldn't get anywhere. Plus I just don't think load sharing is a good idea for residential. Just charge one, then the other without the added expense of yet another EVSE + electrical work if its not needed...and without waking up in the middle of the night to go unplug one EV and plug in the other.

Brad, the Dryer Buddy guy is local here in Southern Nevada. I just contacted him and asked if he could provide some 50A or 60A solution that forgets about the dryer part, and instead automatically switches power from EV#1 to EV#2 when EV#1 has completed its charge. Same theory as the dryer switching. I imagine you could use the Tesla Level-2 charging cable that comes with the car?

Hopefully he will respond soon and I will let you know.
 

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Discussion Starter · #4 ·
One such idea of charging two cars sequentially was to use the charging indicator and charge inhibit on the Siemens VersiCharge. I *think* if you wire them cross connected so that when one is charging the other is inhibited, whichever one started charging first would finish, then the other would start charging. But I think I’d rather do shared simultaneous charging.... maybe I’m trying too hard?
 

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.... maybe I’m trying too hard?
On my end I need to fully charge a 17kWh PHEV everynight, allowing for close to 100% All-E usage the following day.
The Bolt doesn't need to be charged every night here. Considering my typical driving habits, one Hill Top Reserve charge every 3-4 days could suffice. But would still need at least both EV's charged during the same overnight 2-3 times a week.

I surmise on your end, you have a 60kWh battery + a 80 or 90kWh battery. Unless the daily commute for either driver is like really, really long, seems you can easily get away with alternating each EV, every other night using one charger.
 

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The Tesla wall chargers work great for this application - no internet required - you can have one master and up to 3 slaves sharing a single circuit.

I use 3 wall chargers every night - it just works.
 

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Discussion Starter · #7 ·
daveo4bolt, thanks for the push in the tesla interconnected EVSE direction.

Shotel, she drives 84 miles round trip with occasional day trips to any point in South Carolina (we're very near the center of SC). This is why the Tesla super chargers are important to her... we don't have enough CCS chargers in the state yet. My daily commute is 52 miles, but i'm on 24/7 call at work, so any given day I may have to drive that twice. It occurs to me that with the Bolt's portable charger at 12amps, I need to charge 4.5 hours / day and with the tesla capped at 30amps, she'll recharge in a few hours too.... for a worst case of 42 amps on a 50 amp circuit. Seems workable!

Thanks for the input guys!
 
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