Stand Alone Solar Arc-fault protection devices.

[x98myers7]

anyone aware of any AFCI standalone solutions yet?

as this big scary article out of AU indicates... essentially, no central inverter system even with AFCI is "safe"

Solar fires

DC arc faults on solar PV systems have been identified as the root cause of over 250 domestic and commercial building fires in Australia

www.acsolarwarehouse.com

basically, they suggest only micro-inverter solutions are acceptable. what's the truth?

 

[FilterGuy]

anyone aware of any AFCI standalone solutions yet?

as this big scary article out of AU indicates... essentially, no central inverter system even with AFCI is "safe"

Solar fires

DC arc faults on solar PV systems have been identified as the root cause of over 250 domestic and commercial building fires in Australia

www.acsolarwarehouse.com

basically, they suggest only micro-inverter solutions are acceptable. what's the truth?

That is an interesting article. I did not see anything that was factually incorrect, but it failed to mention an important point: The vast majority of the arc faults are serial arc faults.
EDIT: Added this
It is far more common for one of the many connections in a string of panels to come loose (Serial Arc Falt) than it is for conductors to touch each other (Parallel Arc Fault) or touch ground (Ground Ark Fault).
That is why the NEC requirement is for detection and isolation of serial arc fault but there is no requirement for parallel arc fault protection.

I got the distinct impression they were trying to scare folks away from string inverters and push them to micro-inverters...so I was surprised that when I went to their site I saw they sold string inverters. Then I saw that they only sell to 'qualified installers' and it all made sense. They put out this article as a tool for the installer salesman. Installers *love* micro inverters because they are so easy for them to install..... but they can be a hard sell because of the added expense. I can see the salesman pushing the fear of string inverters in order to get the micro-inverter sale. During the sales pitch, they will pull out this 'independent report' that shows how horrible string inverters are.

 

[FilterGuy]

I got the distinct impression they were trying to scare folks away from string inverters and push them to micro-inverters.

BTW: I have nothing against micro-inverters. They can be an excellent way to go. I just don't like it when someone tries to pull a fast one.

 

[Ostiepok]

I'm putting in an order for four of these. I only need one, as each unit can handle 4 strings. I'll hopefully be able to report back in the next few weeks, depending how long it takes to ship and when I have time to get it set up in between work and travel. If it works out, I can resell two or three of them. Will probably look for around 50 bucks shipped per unit, that would be pretty much my cost plus shipping.

How did the order turn out, have you received it yet?
Where specifically did you order

 

[EJansen]

How did the order turn out, have you received it yet?
Where specifically did you order

I too am very interested to see your setup and testing of these.

 

[jesse_c]

Not received yet, I had trouble getting my bank to send the international wire transfer. Attempting to place an order through aliexpress instead.

 

[scottvanv]

Hah! Oops, after looking more, I suppose it doesn't - I just saw their response to my question about the Arc Fault needs:

"I promote our new product that is called "Smart PV Safety Controller", which integrates rapid shutdown and arc fault detection. Please see the attached docs for reference."

And then skimmed what they sent - probably should exercise better due diligence before posting next time. :S

Everyone ... I have 32 of their "Smart PV Safety Controllers", two head units and a controller/switch/monitor sitting in my garage, waiting to be installed with my entire system (still ordering the last parts). They're the only parts in the world, that I'm aware of, that could handle rapid shut down and arc fault detection AT the panel. I had to wire money to China, with no third party guarantee, to get them, and Fonrich delivered after a couple of snafus - they're not really set up to handle consumer orders. I actually received first-off-the-line parts, as this is a brand new offering. When I begin testing / building, I'll post the results here, and attached please find a deck they sent me that explains their offering.

 

[x98myers7]

and UL 1699B! seems promising if the price-point is right.

 

[EJansen]

Everyone ... I have 32 of their "Smart PV Safety Controllers", two head units and a controller/switch/monitor sitting in my garage, waiting to be installed with my entire system (still ordering the last parts). They're the only parts in the world, that I'm aware of, that could handle rapid shut down and arc fault detection AT the panel. I had to wire money to China, with no third party guarantee, to get them, and Fonrich delivered after a couple of snafus - they're not really set up to handle consumer orders. I actually received first-off-the-line parts, as this is a brand new offering. When I begin testing / building, I'll post the results here, and attached please find a deck they sent me that explains their offering.

Awesome, post pics of the products if you don't mind.

 

[scottvanv]

Awesome, post pics of the products if you don't mind.

Pics are in the pdf I posted above ...

 

[EJansen]

Pics are in the pdf I posted above

I've seen pics throughout the thread and in the .pdfs - just didn't know if the final product was the same or any different, especially after you mentioned getting first-off-the-line parts.

 

[cs1234]

and UL 1699B! seems promising if the price-point is right.

Is there a UL listing needed for the rapid shutdown portion also?

 

[scottvanv]

I've seen pics throughout the thread and in the .pdfs - just didn't know if the final product was the same or any different, especially after you mentioned getting first-off-the-line parts.

Ah, no, all the same ...

 

[400bird]

Wow, that's amazing I didn't know that even existed.
Can I ask what you paid?

 

[scottvanv]

Wow, that's amazing I didn't know that even existed.
Can I ask what you paid?

I don't remember the details, but the total was around $950, including air shipping from China, for 32 panels, which included 2 "head units" (the wire wrap monitors near the inverter - I think I only need one, but I got two in case the configuration of the inverter room didn't work out to only include one) and the monitoring/shut down switch device.

 

[cs1234]

and UL 1699B! seems promising if the price-point is right.

Do we think they might have UL 3741 listing for NEC 2020?

 

[derekja]

Missing from pictures in the pdf are any close up pictures of the approval markings. I've got a stickler of an inspector here in Canada, the certificate lists a csa approval but if the mark isn't right he's not going to let me use it. Any chance you could post a picture of the marks?

 

[FilterGuy]

Everyone ... I have 32 of their "Smart PV Safety Controllers", two head units and a controller/switch/monitor sitting in my garage, waiting to be installed with my entire system (still ordering the last parts). They're the only parts in the world, that I'm aware of, that could handle rapid shut down and arc fault detection AT the panel. I had to wire money to China, with no third party guarantee, to get them, and Fonrich delivered after a couple of snafus - they're not really set up to handle consumer orders. I actually received first-off-the-line parts, as this is a brand new offering. When I begin testing / building, I'll post the results here, and attached please find a deck they sent me that explains their offering.

I just spent a few minutes going through their web site and am a bit confused on how it all goes together.

The basic rapid shutdown is straightforward.


You can find this diagram and more info here: https://www.fonrich.com/PV-RSD-Main-Controller-pd45186452.html


If the monitor & Gateway gets a shutdown, it sends a signal to the head module which converts it to a DC Power Line Control signal to the Tail modules. When the tail modules detect the signal, they open the PV line.

However, I don't yet see how the Arc Fault protection is integrated with the Rapid Shutdown.

They have a few Arc Fault products.

1) A stand-alone detector that has an alarm out and Modbus communication but is *only* a detector. I am not sure if this can be integrated with the Rapid Shutdown system. (Can the alarm out be wired to the monitor & Gateway to trigger a rapid shutdown? Does the Monitor & Gateway provide the power the Arc Fault detector needs?)
2) An integrated stand-alone box that contains the detector and a set of relays that will disconnect the PV strings when an arc is detected. This product seems to be completely independent of the rapid shutdown system.
3) A DC monitor system that can detect arc faults and DC leakage (Ground Faults) but it looks like there are a lot of different components are needed to put it all together. It is also not clear how/if it would integrate with the rapid shut-down system.

Overall, it looks like they have some interesting solutions but implementing Ground Fault, Arc Fault and Rapid shutdown is going to require a lot of gear. I could not find pricing but it looks like this is targeted at commercial solar plants so it is likely to be quite pricy. I suspect that by the time you spend the money on this, you would find it cheaper and easier to buy an inverter that supports the functions more directly.

The good news is that the question posed in the original post of this thread has been answered: Yes! There is at least one stand-alone Arc Fault protection product on the market.

I will watch this thread with the hopes of learning more.

 

[jesse_c]

Got a set of four of these. Each one supports up to 4 strings, so I'll likely be reselling 2 of them once I figure out hookup.
They are designed to be in a solar combiner box that the company sells, with relays and a control module, but I'll be using them with a Tigo system triggering on the alarm signal. Pen for scale.

There are no approval marks on this individual component whatsoever (ETL / UL / CSA), I think those would typically also be on the combiner box they sell.

 

[scottvanv]

I just spent a few minutes going through their web site and am a bit confused on how it all goes together.

The basic rapid shutdown is straightforward.

View attachment 114160
You can find this diagram and more info here: https://www.fonrich.com/PV-RSD-Main-Controller-pd45186452.html


If the monitor & Gateway gets a shutdown, it sends a signal to the head module which converts it to a DC Power Line Control signal to the Tail modules. When the tail modules detect the signal, they open the PV line.

However, I don't yet see how the Arc Fault protection is integrated with the Rapid Shutdown.

They have a few Arc Fault products.

1) A stand-alone detector that has an alarm out and Modbus communication but is *only* a detector. I am not sure if this can be integrated with the Rapid Shutdown system. (Can the alarm out be wired to the monitor & Gateway to trigger a rapid shutdown? Does the Monitor & Gateway provide the power the Arc Fault detector needs?)
2) An integrated stand-alone box that contains the detector and a set of relays that will disconnect the PV strings when an arc is detected. This product seems to be completely independent of the rapid shutdown system.
3) A DC monitor system that can detect arc faults and DC leakage (Ground Faults) but it looks like there are a lot of different components are needed to put it all together. It is also not clear how/if it would integrate with the rapid shut-down system.

Overall, it looks like they have some interesting solutions but implementing Ground Fault, Arc Fault and Rapid shutdown is going to require a lot of gear. I could not find pricing but it looks like this is targeted at commercial solar plants so it is likely to be quite pricy. I suspect that by the time you spend the money on this, you would find it cheaper and easier to buy an inverter that supports the functions more directly.

The good news is that the question posed in the original post of this thread has been answered: Yes! There is at least one stand-alone Arc Fault protection product on the market.

I will watch this thread with the hopes of learning more.

There's a tail module on every panel, thus why I have 32 tail units to go with my 32 panels. The arc fault circuitry is built into every tail module, not the head unit, which is used to help monitor the performance of the system. I haven't researched the details, but I highly doubt the tail units switch open with a pro-active signal, since they have a heartbeat signal, and will open if they don't receive it. The cost was $950 for all pieces for me, landed in the US. (They're selling at wholesale prices to even us DIYers.) Don't confuse what I bought with the pic just above ... pretty sure that's a string level detector ...