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Will SolarCity H6 work in a rogue off-grid setup?

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I've gone rogue off grid. 7 kilowatts of panels and way too much lithium batteries.
I noticed some Tesla related inverters like the SolarCity h6 hybrid inverter that are enticingly cheap like $700. I like the high-voltage aspect and could arrange my batteries to be the correct voltage and I'm wondering what you guys think about using this inverter in a purely off-grid situation bought on clearance?
The seller thinks it requires a Tesla powerwall 2 but that's confusing me because I thought the the Tesla battery has a DC converter in it so it won't put out that high voltage.

It needs a very high voltage battery like 570 volts. It looks like the reason they're stepping solar panel voltage up instead of down like a regular mppt charge controller is because they're trying to reduce the highest voltage a bit. Can you imagine how high the panels voltage would go on a frosty morning the other way around?
It has 2 mppt 4,500w charge controllers built-in.
With an ideal panel voltage of 370v.
It says off it's off grid and grid tie capable.
Needs a 570 volt battery.
I think It must not have a giant heavy transformer because it's meagher 6800 Watt surge capacity is not double its continuous rating like it would be with an outback or Schneider?
If I max out its charge controller and want more solar what type of charge controllers work with this voltage?
There's some question as to whether it will work with a do-it-yourself powerwall?

Can it be done without being connected to Tesla?
Will this inverter even turn on without Tesla brand batteries?
Can I stack two inverters?

Got to love (& respect) that high voltage!

Look on page 91or 101 depending on which number you're looking at of this 146 page PDF file for the specifications.

Solar city manual H6 Hybrid Inverter_v1.1_02_03_17 release[22838].pdf
 
I can't add much here but will watch with interest this thread.
I have two of these inverters, neither yet in service. My interest is a grid tie only, no off grid or battery use contemplated. Though I AM interested in the capabilities.

If the first one goes into service with no surprises, I will buy several more.

The above linked to manual makes the inverter sound about like the inverter in a PW2. I wonder if the PW2 inverter is Delta? I wonder if the low cost availablitly of this product is the result in a change of direction in product development at either Sun City or Tesla Energy? It is clearly an unsuccessful product; I wonder why?

The documentation says the H6 is to be used only with Power Walls. I believe PW2 batteries are 48v nominal and the H6 wants much higher. Did the PW1 use higher battery voltage?
 
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I wonder if the low cost availablitly of this product is the result in a change of direction in product development at either Sun City or Tesla Energy? It is clearly an unsuccessful product; I wonder why?

The documentation says the H6 is to be used only with Power Walls. I believe PW2 batteries are 48v nominal and the H6 wants much higher. Did the PW1 use higher battery voltage?

I know there were some powerwall ones that use higher voltage I don't know if they were all that way. I also know that the powerwall 2 originally came in two variants. One had a built-in inverter which is the one they're selling now and the other was just a battery they called it's the DC Powerwall. As far as I can tell they've mainly discontinued the DC version specifically I've noticed for other countries. but as for the United States it seems like it was left open-ended like it's probably available for only select customers who have hi voltage inverters possibly that are tethered to a powerwall 1 and where are they need a power wall replacement they'll probably get the DC version of the powerwall 2.

Was a change in direction of SolarCity and Tesla? Yes it seems there was and that left a great deal of these inverters with no practical use which explains why they're so cheap. Tesla originally announced the DC version of the powerwall 2 and I'm pretty sure SolarCity was producing these inverters gearing up for it's release. When Tesla decided not to proceed with the powerwall 2 DC version that's probably why these inverters are in this situation.
 
The specs on the powerwall 2 say it's a 48 volt battery which is strange that they would choose that voltage considering it's all in one unit so it would be even safer to use higher voltage compared to a DC high-voltage powerwall disattached from its matching inverter like they have done in the past.
 
Even though I have a PW2, I'm not "up to speed" on Power Wall lore. Thanks for mentioning that there are/were DC PowerWalls. So, this "H6 Hybrid" is dependent on a DC PW as a battery rather than tapping into the current PW2 somewhere.
Though it seems, if one could learn enough about the unavailable DC PWs, a battery could be configured to work with the H6.

I'll continue to consider my H6s to be just plain grid tie PV inverters.
 
I bought one and I'm trying to figure this out too. Seems like a very efficient inverter with good specs, especially on the MPPT. I hooked it up off-grid to solar panels and it does turn on and supplies power without a battery, but will go into fault mode once the panels can't supply enough power to the load. The high voltage battery requirement is a real pain and this is what I'm trying to figure out, whether it will work with a non-Tesla battery. Another thing I'm trying to figure out is a low cost balancing solution for a 500v lithium pack. That's a lot of cells.

I was also confused about the Powerwall 2 models with and without inverter, as well as the voltage, as it says internal voltage is 50v.

Any updates?
 
Has anyone tried connecting a battery pack directly into the PV input of this hybrid inverter? Since the PV input voltage range for this unit is a nominal 380V, this closely matches the pack voltage of several popular electric vehicles of which salvaged lithium packs are readily available at a low cost. Also, the specs state that the operating PV input voltage range is quite wide (85V to 550V) which could allow inverter operation with many different pack voltages. There could be issues with overcurrent so any tests should be done with a fast acting HVDC fuse on the battery. But since this inverter in off-grid mode is designed to match the solar input power with the load, maybe it would just work... Solar charging the pack could be accomplished with a simple constant-voltage arrangement using a separate circuit. I really like the idea of figuring a way to repurpose these inverter units for off-grid applications, and of course the ultimate hack would be to reprogram the firmware to bypass the PW2 CANBUS communication and unlock its full functionality including MPPT charging and activating the built-in battery charger when AC power is present.
 
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The simple constant voltage device that you refer to would have to be a DC to DC converter that would be controlled by some device that monitors the battery. This most likely device would be a BMS that could handle the 100 or so cell groups in abattery of that voltage. That kind of BMS is available in the DIY EV marketplace for around $1000
My guess is one could spend a lot more money on that kind of project than it would be worth given that the typical inverter lasts 7-10 years. There has to be a good reason Tesla abandoned DC coupling in favor of AC coupling.
 
Even though I have a PW2, I'm not "up to speed" on Power Wall lore. Thanks for mentioning that there are/were DC PowerWalls. So, this "H6 Hybrid" is dependent on a DC PW as a battery rather than tapping into the current PW2 somewhere.
Though it seems, if one could learn enough about the unavailable DC PWs, a battery could be configured to work with the H6.

I'll continue to consider my H6s to be just plain grid tie PV inverters.

I FINALLY got one of these hooked up! It seemed to almost work. It complained about, as I recall, line frequency and line voltage. From other sources, my frequency is dead on 60hz; the Delta was reporting 59.7. Line voltages were a bit high, around 245. I suspect that the unit may be configured for other than USA. The unit demands an unknown password before it will reveal the grid parameters it is configured for.

I've never before set up a string inverter so I lacked some self confidence. I jumped the panel wires over to a SunnyBoy 4kw and it worked without issue so I don't believe I have any panel wiring problem. I'm running four strings of 9 panels combined which gives me the needed ~300vdc.

Both the seller and Delta have declined to supply any clues.
 
I FINALLY got one of these hooked up! It seemed to almost work. It complained about, as I recall, line frequency and line voltage. From other sources, my frequency is dead on 60hz; the Delta was reporting 59.7. Line voltages were a bit high, around 245. I suspect that the unit may be configured for other than USA. The unit demands an unknown password before it will reveal the grid parameters it is configured for.

I've never before set up a string inverter so I lacked some self confidence. I jumped the panel wires over to a SunnyBoy 4kw and it worked without issue so I don't believe I have any panel wiring problem. I'm running four strings of 9 panels combined which gives me the needed ~300vdc.

Both the seller and Delta have declined to supply any clues.
I hooked up my H6 yesterday. I did a few tests and it seemed to be pulling power out of my batteries completely off-grid & had excellent surge capacity. I disconnected the batteries and it was able to start up a Shop-Vac that in rushed twice as much as the inverters surge rating. Even with low panel wattage it still started the motor and ran it at a reduced speed. Amazing! But on day two it no longer functions off grid. The only thing I can get it to do now is grid tie. It will actually pull 6000 Watts out of my batteries and export to the grid for 5 minutes upon boot up. I got into the password menu there's only some minor AC settings in there. And yes frequency is in there. but it says right on the side there's a sticker with all the specs and the nominal frequency on my unit is 60 hertz according to that sticker.
 
Has anyone tried connecting a battery pack directly into the PV input of this hybrid inverter? Since the PV input voltage range for this unit is a nominal 380V, this closely matches the pack voltage of several popular electric vehicles of which salvaged lithium packs are readily available at a low cost. Also, the specs state that the operating PV input voltage range is quite wide (85V to 550V) which could allow inverter operation with many different pack voltages. There could be issues with overcurrent so any tests should be done with a fast acting HVDC fuse on the battery. But since this inverter in off-grid mode is designed to match the solar input power with the load, maybe it would just work... Solar charging the pack could be accomplished with a simple constant-voltage arrangement using a separate circuit. I really like the idea of figuring a way to repurpose these inverter units for off-grid applications, and of course the ultimate hack would be to reprogram the firmware to bypass the PW2 CANBUS communication and unlock its full functionality including MPPT charging and activating the built-in battery charger when AC power is present.
I haven't tried hooking my batteries directly to the PV input yet but if I can't get it working any other way I will definitely be trying that. In theory it would work great because it seems like if it wasn't trying to feed the grid it wouldn't be able to do any mppt sweeps in that configuration. the only problem is it would not be charging the batteries set up like that so you wouldn't be able to utilize it as a solar battery charger. It would only function as a stand-alone inverter. so you would need a separate charge controller and I'm not sure there's many cost-effective charge controllers then go up to 500 volt battery. you could take the AC power that comes out of this thing and run it through a different inverter backwards. and if that battery were designed to run off of a high-voltage battery could be used to charge the batteries. What a pain in the rear
 
My fuses were bad. that's why it wouldn't pull power out of my batteries any longer. I accidentally connected them without using the pre-charge resistor once the other day. now I'm back to exporting battery power to the power company but not able to charge the batteries using the solar yet.
 
Today I hooked a 230 volt battery to the inverter where the solar panel is supposed to be connected. It seemed to work okay for small loads like 600w but when I turned on the 1.4kw Shop-Vac that has a startup surge of kw6 the inverter shut down with an error and said arc fault. Then I tried exporting to the grid and it was working for a while until my battery had a sudden change in voltage because it was actually my Toyota Prius and the engine was starting up. That gave the arc fault error again and it shut down. It would sort of randomly give the arc fault error and shut down so I'll say as of now it's simply not reliable the way it is. that's too bad because the solar panel voltage input ranges from 85 volts up to 570 which would have made it the perfect setup for hooking straight to a wide range of electric vehicle batteries at their stock voltages. I'm thinking maybe I should have twisted the 20 foot wires around each other that stretched between the battery and the inverter. Maybe that would help?
 
I tried putting a bunch of water heater elements in parallel and running the power positive wire from the Prius battery through the elements and then on its way to the inverters solar panel input. Doing it like this I can make it work a little more stable but I'm still having the arc fault error. Does anybody think an inductor might work? I hear they're supposed to remove high frequency from the circuit and I heard that the arc fault detector is looking for the high-frequency signature of an arc. So it makes sense that it might help but are there different size inductors for different frequencies? What frequency am I trying to filter out?
But then there is the issue of when I disconnect the negative wire between the Prius and the inverter there will be a voltage Spike come from the inductor into the inverter. I figure the spike might be as high as three thousand volts. It's just a sort of guess though am I wrong? People say to put a diode across the inductor but backwards causing any Spike to be sent back to cancel itself out. They say this is to protect the transistors but what's to say it won't just blow up the diode?
 
CoinHead? How did you get into the Password menu? I have one of these that I am trying to install and it’s frustrating me to no end. There is supposed to be an override to allow this H6 to charge batteries from Grid power if you have too many non-sunny days and your batteries get low.

I have it hooked up to a hand built 160v LiPo battery bank and 6kW of Solar Panels. But have plans to expand both to the systems maximums.