SMA Sunnyboy Secure Power workaround for Rapid shutdown

[Ampster]

There must be a setting somewhere that tells the inverter to look for a signal from the RSD subsystem.. How else would those inverters be installed where RSD is not required? I presume there are installations in the world where RSD is not required? I suspect it is a fail safe implementation that shuts off the inverter if no RSD interface is present. Again, I have no specifics and for safety reasons would not recommend it but I also agree that the risk of a family starving during an outage is far greater than the risk that firemen will need to be on your roof during and outage.

[Bobodude]

The Sunnyboy Secure Power output does not energize the main panel. It outputs to a external duplex socket therefore not a danger to utility lineman. Yes it would allow the panels to be fully energized but a fire at the same time of an outage? Chances are astronomical.

[Bobodude]

My betting money says they tell you that is "proprietary information" . and offer you no help.

After google search, I found the a description of the Texas Instruments interface for the Sunspec protocol. Very complex FSK signal. It seems overkill for a simple signal that turns on it off a panel.
I think the only solutions are either to come from SMA in a Firmware update or to remove the device all together. I think there was a Early RSD that did work with the Secure Power option but I don’t know if those are still available. I’m at a dead end.

[SunEagle]

My betting money says they tell you that is "proprietary information" . and offer you no help.

I agree. Most companies that have something that can hurt someone either ask for a signed letter accepting responsibility or will never provide access to change their product.

[Mike 134]

SMA uses a JMS-F Sunspec RSD. There are no external wires to activate the device. The Sundpec communications protocol that activates the device rides on top of the dc panel lines coming into the inverter. So possibly the signal could be synthesized and sent down the dc lines to turn on the device on a grid shutdown, obviously with the main panel isolated from the grid. I guess a call to SMA to get the description of the protocol.

My betting money says they tell you that is "proprietary information" . and offer you no help.

[Bobodude]

Back to the issue that Bobodude has. There has to be a way to disconnect the rapid shut down circuit as a workaround to get power when the grid is down. Yes, I understand that would be risky but everything in life has trade offs. The RSD circuit on my inverter is two wires. Hopefully it is that simple for him without a trip to the roof. A simple Google search of the title to this thread turned up some hit that might be promising. I do not know enough about the SMA inverters to evaluate those links.

SMA uses a JMS-F Sunspec RSD. There are no external wires to activate the device. The Sundpec communications protocol that activates the device rides on top of the dc panel lines coming into the inverter. So possibly the signal could be synthesized and sent down the dc lines to turn on the device on a grid shutdown, obviously with the main panel isolated from the grid. I guess a call to SMA to get the description of the protocol.

[Ampster]

Back to the issue that Bobodude has. There has to be a way to disconnect the rapid shut down circuit as a workaround to get power when the grid is down. Yes, I understand that would be risky but everything in life has trade offs. The RSD circuit on my inverter is two wires. Hopefully it is that simple for him without a trip to the roof. A simple Google search of the title to this thread turned up some hit that might be promising. I do not know enough about the SMA inverters to evaluate those links.

[bcroe]

There are a lot more reasons than that!

1) It is currently the most expensive form of power we have. So utilities have to weigh the reliability of nuclear over the risk of doubling people's power prices.

2) It takes ~20 years to build a new plant, so utilities have to both pay for the new plant AND figure out how to generate power in the interim.

3) They don't load follow very well. It is very difficult to ramp power up and down and you absolutely can't shut them down and restart them every day. (In fact, the system that adjusts power was the first step in the process that led to the Three Mile Island meltdown.) Thus they are best reserved for base load power.

If an area's load varies from, say, 10 to 30 gigawatts, it makes sense to supply that first 10 gigawatts with nuclear (as long as you can afford it.) It's reliable and long-lasting power. Beyond that, expenses rise rapidly for not as much benefit.

OK, I will back off from the 100% figure. We started with technology
from the war (took nothing like 20 yr to get the BOMB). They have
been managing pretty well. We have learned a lot, need to put more
resources on better (in every respect) plants, and stop stalling.

Yes all the above are problems, that does not mean they cannot be
managed. Current power has to deal with ramp up/down. Hydro,
pumped storage where practical, utility batteries, cutting off renewables
if needed, some industrial loads might be willing to cooperate. The
COST of a solution is not even on my radar, compared to my life.
Bruce Roe

[SunEagle]

There are a lot more reasons than that!

1) It is currently the most expensive form of power we have. So utilities have to weigh the reliability of nuclear over the risk of doubling people's power prices.

2) It takes ~20 years to build a new plant, so utilities have to both pay for the new plant AND figure out how to generate power in the interim.

3) They don't load follow very well. It is very difficult to ramp power up and down and you absolutely can't shut them down and restart them every day. (In fact, the system that adjusts power was the first step in the process that led to the Three Mile Island meltdown.) Thus they are best reserved for base load power.

If an area's load varies from, say, 10 to 30 gigawatts, it makes sense to supply that first 10 gigawatts with nuclear (as long as you can afford it.) It's reliable and long-lasting power. Beyond that, expenses rise rapidly for not as much benefit.

While all that is true power generation costs vary from place to place in the US.

All I am saying is that right now there is no guarantee that renewable power will be available 24/7 for everyone. You will still need base generation and either peakers or stored energy to fill in the blanks.

[jflorey2]

In ILL we are heavily into nuke, the only real obstacle to going 100% is political.

There are a lot more reasons than that!

1) It is currently the most expensive form of power we have. So utilities have to weigh the reliability of nuclear over the risk of doubling people's power prices.

2) It takes ~20 years to build a new plant, so utilities have to both pay for the new plant AND figure out how to generate power in the interim.

3) They don't load follow very well. It is very difficult to ramp power up and down and you absolutely can't shut them down and restart them every day. (In fact, the system that adjusts power was the first step in the process that led to the Three Mile Island meltdown.) Thus they are best reserved for base load power.

If an area's load varies from, say, 10 to 30 gigawatts, it makes sense to supply that first 10 gigawatts with nuclear (as long as you can afford it.) It's reliable and long-lasting power. Beyond that, expenses rise rapidly for not as much benefit.

[bcroe]

I have always supported solar but will continue to post that we must have a collection of different power generators and until someone comes up with a renewable source for 100% 24/7/365 supply I will say we still need both fossil fuel and nuclear power generators. But some people may be lucky enough to get 100% power from renewables. I don't think everyone will be so lucky.

In ILL we are heavily into nuke, the only real obstacle to going 100% is
political. I certainly think the 70s designs need total rework, thorium
would be ideal. We are always going to need some fossile fuels, need
to restrict it to vehicles and temp portable apps. Bruce Roe

[SunEagle]

If I'm worried about power being out for an extended time a generator is the only reliable alternate source of power. You just cannot count on there being sun to recharge the batteries. Just last week our weatherman commented that we have had 9 days without sun. Granted SW USA it's unlikely but days and days of smoke from fires are not out of the question.

Good point. Unfortunately smoke is not the only thing that can block the sun and reduce power production.

I have always supported solar but will continue to post that we must have a collection of different power generators and until someone comes up with a renewable source for 100% 24/7/365 supply I will say we still need both fossil fuel and nuclear power generators. But some people may be lucky enough to get 100% power from renewables. I don't think everyone will be so lucky.

[Mike 134]

If I'm worried about power being out for an extended time a generator is the only reliable alternate source of power. You just cannot count on there being sun to recharge the batteries. Just last week our weatherman commented that we have had 9 days without sun. Granted SW USA it's unlikely but days and days of smoke from fires are not out of the question.

[SunEagle]

I think maybe I haven’t presented my problem in the right context. At my last home in Nevada, I designed and installed myself a ground based array with a Trace SW-4048 inverter. I had a 10kwh battery bank. If the power went out, and it did on a regular bases for days, the inverter could output its full 4kw to a separate sub panel that had all my critical circuits wired to. This included frig, freezers, minimal lighting etc. When I moved to Phoenix I also wanted the same functionality.
Obviously, now I’m 72, I’m not going to install my system like I did in Nevada but I want to be self reliant on power.
With that said, when I contracted to have a 8.8 kw system installed I requested the Sunnyboy 7.0 with the Secure Power option that will output 2 kw to a single duplex receptacle. Unfortunately the installer did not realize that option would not work with the required rapid shutdowd devices mounted on each panel.
So here I sit with 8.8 kw worth of power I can’t access in an extreme emergency. The installed blame’s the NEC and I’m in the middle.
I only want to provide for my family in a situation when power could be out for an extended period of time. In these times of uncertainty, you would want to do the same. Worrying about a house fire and safety of fireman would be my first priority in normal times. These are not normal times. When the sh*t hits the fan, the dynamics change dramatically. You might think the same.

When the sh*t hits the fan electrical power will not be a priority for me and my family.. But each person has their own priorities.

[SunEagle]

I wouldn’t remove the RS devices on the panels. I would either setup a fake 240 v injection into the main panel to simulate the grid hot with the main bkr open or simulate the “on” signal the inverter sends to the RS devices to again fake out the devices. Again, the system would first absolutely be separated from the grid to prevent back feed.

Good luck introducing a fake 240V into the panel to simulate the grid. From what I have heard there isn't any hardware that will work well. The best condition is that it will not work the worst it will burn something up.

Why can't people just believe that if the grid is down their pv system will not produce anything unless they have a hybrid inverter and batteries.