diy solar

diy solar

All in one hybrid inverter with built in Arc Fault Protection?

GXMnow

Solar Wizard
Joined
Jul 17, 2020
Messages
2,698
I searched a bit on here and Google looking for what is out there. I still want to add a few more solar panels to my system, and I am torn between DC coupling or more Enphase microinverters and just adding to my existing AC coupling setup. One of my big reasons for not going DC has been the added cost of needing Arc Fault Protection now. But then I saw that there are now some charge controllers and inverters that have the Arc Fault detection built in.

Both Outback and Midnight Solar have added this to their top line of solar charge controllers, but they are now pushing close to $1,000 and they still won't talk to my existing system, so I will need another monitoring app. The Schneider charge controller is cheaper, but adding Arc Fault protection adds another $600+ to the cost. The Sol-Ark inverters now have Arc Fault protection built in, but they are very expensive for their power ratings. I know they are based on Deye inverters, and other companies rebrand them as well. I don't actually need another inverter, but if I did attach one of these all in one style units onto one of my battery banks, I would have a complete portable solar power station. The battery cabinets are already on wheels. When it is in my home, the batteries parallel together, and the solar input of the all in one could charge the batteries. But I could unplug the system with the All In One unit, take it ut, and use it is a backup power supply, or even give a charge to an EV off the inverter.

So here is my question...
Do any of the smaller Growatt, MPP, PowMr, or other lower cost All In One hybrid or even off grid inverters have built in Arc Fault Protection like the So-Ark? The inverter output will never be grid tied. 99% of the time, I won't even be using the AC output. But I might end up using it as the power source for a Plug In Hybrid or EV car in the future. That way I can charge from just stored solar. I think even US market cars would work just fine from a single phase 230 volt source. So an EU model should work, but I would want 60 Hz. I can always use an autotransformer to drop it to 115 volt if needed. At my house, the Schneider will still be my Split Phase 120/240 inverter. The All in One will mostly just be a solar charge controller.

Any ideas for an inverter that fits this plan?
 
If you're willing to look at cheap inverters with arc fault why not look at cheap chinese microinverters? Here's a video review fromport posted.

A Hoymiles microinverter has the protection built in, here's a link to their arc-fault declaration, ncsolarelectric can probably provide some $/W costs as he just purchased some.
 
Last edited:
Most modern AIO's have ark fault detection built-in.
You just have to check the specs on the one you choose.
 
I didn't look at cheap microinverters, because, if I am going to stay AC coupling, I might as well stick with the Enphase to keep it all managed together. I could save some money, but the issue of needing another separate monitoring system with no other benefit didn't seem worth it. But I will see how much it can save.

If I get direct DC charging, then it is a benefit, and I can accept the extra hassle of yet another system. But going with just a charge controller, I didn't think was enough. The Midnight Solar charge controller looks great, and cost wise, is not too bad, and it will give me the most efficient battery charging with proper arc fault etc. But that is all I get. For about the same price, a Deye or Sunsink etc. can give me almost as efficient DC charging, AND I get a separate off grid 3,000 watt inverter that I can use as an EV charger. And I can roll it out with half my battery bank as a power station. Not really portable as it does weigh around 300 pounds, but it is 18 KWHs of battery. That could easily put over 30 miles of range into a stranded EV. 3,000 watts is around 10 miles per hour of charging. I would not want to go any smaller, and many are 5,000 watts. The small Growatt 3,000 looks great at $800, but I can't find mention of Arc Fault protection.

On the Deye/Sunsink, do they send the signal for the per panel cut off boxes? It looks like the Sol-Ark version does, but it looks like an add in box that might not be part of the Deye base units.
 
Whatever you do, please be careful ; -) the bolt battery doesn't have the best history.
 
According to GM, after their investigation with LG, they claimed the only ones that caught fire had 2 faults. One of them was stressed and torn tabs from the robot welding the tabs to the bus bars. I inspected all of my tabs, and none of them show any sign of stress or damage. Also, all of the ones that caught fire were shortly after a full fast charge to 100%. I charge very slowly to just 90%. The highest charge current I have ever hit was only 50 amps into 720 amp hours or 0.07 C rate. There is no stress on the cells, ever. My highest discharge rate sill has not topped 120 amps. So again, I never discharge over 0.2C rate. The cells are rated by LG for continuous 1C charge and 3 C discharge. And in the car, they are getting all bounced around in traffic. And there was a total of 13 Chevy Bolt battery fires out of 140,000 cars sold. As you can probably guess, I am not worried about this. That being said, the cells are inside steel cabinets, out at the far end of my garage, on wheels, and a single Anderson plug to each cabinet. And I have a heat alarm on them and a smoke detector above them.
 
That being said, the cells are inside steel cabinets, out at the far end of my garage, on wheels, and a single Anderson plug to each cabinet. And I have a heat alarm on them and a smoke detector above them.
But you can never leave the house ever again LOL
 
$675 for the Midnight charge controller with Arc Fault built in. Do you get enough benefit from an AIO to go that direction?

How much PV are you looking to add? I thought it was like 3,000 watts? Pretty sure the 150 can handle that, just lots of little parallel stings of panels.

The classic 150 is where I'm leaning right now when I get to the point of adding more PV.

 
That Midnight charge controller is certainly on my list. It's only a little more expensive than the Schneider 60 amp 150 volt, and has the arc fault, so it is a much better deal. But for about the same money, we could get the Growatt with the charge controller and a 3,000 watt inverter. But I still can't find if it includes the arc fault protection. I am starting to think it doesn't. Probably have to step up to the 5,500 watt at over $1,000 to get it. So that makes the Midnight charge controller a better deal.

With the space I have available, I think I can easily fit about 2,000 watts of panels. So I really only need 40 to 50 amps of charge controller. If I can get a decent deal on the panels (including shipping them) I might get a few extra and add the awning on the east side of my house.

I did find a surplus dealer that is not too far from me, in Santa Paula, CA, that has a stock of used 290 watt Trina panels at $75 each. I might have to rent a minivan and go pick some up. They say they have about 4,000 in stock. They are older poly panels, but that is super cheap.
 
Can I one-up the question: Does any AiO (or just a solar charge controller) integrate both Arc Fault and RSD initiation? That is one thing that makes the Schneider SCC's extra expensive, needing to add the MPPT-RSD is over $700 not including the panel modules.
 
I have been looking for a year, and still have not found that. I am shocked no one has come up with it all in the charge controller for a reasonable cost. The Midnite Classic series are the only ones I have found that do Arc Fault, but they only minimize the arc by dropping to zero current from the panels. That does work for a series arc from a bad connection or broken wore. But if it is a bare wire arcing to the racking, it can't stop it. If it could also trigger the Tigo RSD boxes, that should shut down the other arcing as well. I think the Schneider setup does do that, but the arc fault etection unit costs as much as the whole Midnite charge controller.
 
That does work for a series arc from a bad connection or broken wore. But if it is a bare wire arcing to the racking, it can't stop it.
That would be a ground fault and is also included in the Mindnite. Also, there really isn't potential (electrical potential) from one solar conductor to ground.
If it could also trigger the Tigo RSD boxes, that should shut down the other arcing as well. I think the Schneider setup does do that, but the arc fault etection unit costs as much as the whole Midnite charge controller.
I was hoping for that and it's part of the reason why I waited to make a decision. But, Schneider doesn't document an arc fault triggering a remote shut down.

I believe the Midnite relays arc fault over modbus. I could open a relay to kill the RSD in case of a detected arc. It wouldn't take much additional work. Just add a Sonoff or other smart wifi relay in line to the RSD transmitter.
 
I was hoping for that and it's part of the reason why I waited to make a decision. But, Schneider doesn't document an arc fault triggering a remote shut down.
The MPPT Disconnect RS is an accessory for the Conext™ MPPT 60 150, MPPT 80 600, and MPPT 100 600 charge controllers. It provides a disconnect for the photovoltaic (PV) circuits, an integrated Rapid Shutdown transmitter, and arc fault detection for enhanced safety.
 
Back
Top