5 ms·

This is a very nice development, but it is tackling the easy stuff. I'd love to see an open source inverter that can operate in stand-alone mode or in grid conn

This is a very nice development, but it is tackling the easy stuff. I'd love to see an open source inverter that can operate in stand-alone mode or in grid connected mode. All of these grid connected devices with closed source are a massive risk, especially given how small and cheap a WiFi or cell modem is nowadays.

Rebelgecko 8mo ago
Deye/Solark famously bricked a bunch of inverters remotely not long back
- jacquesm 8mo ago
  I opened up all inverters here and disabled all remote access hardware physically. I'd rather not have a warranty than the risk of either seeing my critical hardware hacked or bricked by the manufacturer. And given the size of these (one is a 17KW unit) the risk of real damage to my home circuits and/or the feed is not imaginary, just rapidly turning it off and back on would already be a big problem, especially on a really sunny day. I try everything I can to not trip the breakers on the inverter around solar noon on sunny days because the amount of current is non-trivial, even on a 960V system. It will generate an absolutely spectacular arc.
  - organsnyder 8mo ago
    My SolArk inverter came with a wifi dongle that uses Modbus over RS232 to interface with the inverter. I removed the dongle and connected a Pi to provide a Modbus-over-TCP interface that I can use from Home Assistant. I got more control (the officially-supported Modbus interface is read-only), and SolArk no longer has any access to my equipment.
    - jacquesm 8mo ago
      That's a nice trick. I should try that.
f_devd 8mo ago
A UPS-style grid connected inverter (with phase balancing) would be significantly more complicated by also significantly more useful. More in the critical/specialized part category, rather than near-commodity (like MPPT/BMS)
bityard 8mo ago
They are pretty clearly targeting DIYers and enthusiasts who like tinkering with off-grid solar. Grid-connected is an entirely different ball game. You will not see any open source projects there, or at least not any that anyone will want to use. Let's think about why not. Anything grid-connected, you REALLY want a licensed electrician to plan and install. And competent electricians will NOT go anywhere near a piece of equipment that is not UL certified. A company producing equipment is NOT going to go through the expense of getting UL certified and then just release their design, PCB, and schematics for free. And I want to be clear that I am a strong proponent of open source hardware, there are just certain situations where the incentives in reality just don't line up. This is one of them.
- jacquesm 8mo ago
  Bollocks. I've been making grid connected hardware for decades, there is nothing magical about any of that. You just need to be careful, use proper fusing and you need to know how to read the electrical code. Competent electricians are licensed professionals who (1) stand to make money on selling gear and (2) have customers that hire them simply because they don't want the hassle or the liability. Obviously a licensed professional is not going to install your home brew inverter, but at the same time if you can design a homebrew inverter you probably don't need a licensed professional anyway. I've rewired lots of homes and have never had an issue with any of this and designed my first inverter when I was 17 to power my room when my betters decided I should go to sleep and cut the power. This stuff is not magic. If someone designs a modern open source inverter I'm definitely going to build and install it. Fortunately insurance companies here are reasonable: if your homebrew device wasn't the cause of the mishap then you are still insured. The one thing they are very strict about is gas, because there is no such thing as a 'fuse for gas'. But if you've properly designed and fused your gear then it should be no less safe than any other grid connected device, even if the magic UL or TUV mark isn't there. The big one is EMI, that can be hard to get right and you need some gear for this, which is why it pays off to pool the money for an open source design to be certified. And once certified of course the design is 'type approved' and frozen, so you can't change any of the hardware without going through recertification. This is expensive, but if you don't do it every other week should still be well within the means of a properly set up open source project. Why the fearmongering? It's not as if we're 12 here.

Rebelgecko 8mo ago

Deye/Solark famously bricked a bunch of inverters remotely not long back

jacquesm 8mo ago
I opened up all inverters here and disabled all remote access hardware physically. I'd rather not have a warranty than the risk of either seeing my critical hardware hacked or bricked by the manufacturer. And given the size of these (one is a 17KW unit) the risk of real damage to my home circuits and/or the feed is not imaginary, just rapidly turning it off and back on would already be a big problem, especially on a really sunny day. I try everything I can to not trip the breakers on the inverter around solar noon on sunny days because the amount of current is non-trivial, even on a 960V system. It will generate an absolutely spectacular arc.
- organsnyder 8mo ago
  My SolArk inverter came with a wifi dongle that uses Modbus over RS232 to interface with the inverter. I removed the dongle and connected a Pi to provide a Modbus-over-TCP interface that I can use from Home Assistant. I got more control (the officially-supported Modbus interface is read-only), and SolArk no longer has any access to my equipment.
  - jacquesm 8mo ago
    That's a nice trick. I should try that.

f_devd 8mo ago

A UPS-style grid connected inverter (with phase balancing) would be significantly more complicated by also significantly more useful. More in the critical/specialized part category, rather than near-commodity (like MPPT/BMS)

bityard 8mo ago

They are pretty clearly targeting DIYers and enthusiasts who like tinkering with off-grid solar. Grid-connected is an entirely different ball game. You will not see any open source projects there, or at least not any that anyone will want to use. Let's think about why not. Anything grid-connected, you REALLY want a licensed electrician to plan and install. And competent electricians will NOT go anywhere near a piece of equipment that is not UL certified. A company producing equipment is NOT going to go through the expense of getting UL certified and then just release their design, PCB, and schematics for free. And I want to be clear that I am a strong proponent of open source hardware, there are just certain situations where the incentives in reality just don't line up. This is one of them.

jacquesm 8mo ago
Bollocks. I've been making grid connected hardware for decades, there is nothing magical about any of that. You just need to be careful, use proper fusing and you need to know how to read the electrical code. Competent electricians are licensed professionals who (1) stand to make money on selling gear and (2) have customers that hire them simply because they don't want the hassle or the liability. Obviously a licensed professional is not going to install your home brew inverter, but at the same time if you can design a homebrew inverter you probably don't need a licensed professional anyway. I've rewired lots of homes and have never had an issue with any of this and designed my first inverter when I was 17 to power my room when my betters decided I should go to sleep and cut the power. This stuff is not magic. If someone designs a modern open source inverter I'm definitely going to build and install it. Fortunately insurance companies here are reasonable: if your homebrew device wasn't the cause of the mishap then you are still insured. The one thing they are very strict about is gas, because there is no such thing as a 'fuse for gas'. But if you've properly designed and fused your gear then it should be no less safe than any other grid connected device, even if the magic UL or TUV mark isn't there. The big one is EMI, that can be hard to get right and you need some gear for this, which is why it pays off to pool the money for an open source design to be certified. And once certified of course the design is 'type approved' and frozen, so you can't change any of the hardware without going through recertification. This is expensive, but if you don't do it every other week should still be well within the means of a properly set up open source project. Why the fearmongering? It's not as if we're 12 here.