SMA Sunny Boy to Sunny Island

[BushMan2000U]

Looking for some help. I have a new system Completly OFF GRID (Generator back -up )with a sunny boy 6.0US-41 and two sunny island 60/48 inverters.
Do i need a grid guard code to set the sunny boy to off grid mode only and is the RS 485 piggy back cards required for both units to communicate for monitoring and Frequency shift. On sunny days the sunny boy pushes 90 amps regardless of what the sunny island is set at and then the sunny boy disconnects. As the battery is not near full i would think there is some communication error. I have exhausted all other SMA tech tips as they only over some models and not much for completely OFF GRID

Any help would be Great

 

[Johneb]

I am not that well versed on SMA products so take this with a grain/box of salt. I would double check your settings on the Sunny Islands. Is it set for the correct batteries/voltages. It could be the Sunny Island is signaling full battery when its not.

 

[Johneb]

Hopefully Hedges will see this and help you out. He uses SB/SI.

 

[Consumerbot3418]

I'm running almost exactly this setup. Don't think @Hedges is off-grid... Do you have a DC Solar trailer, by chance?

I did not need a grid guard code to switch SI to off-grid. RS-485 shouldn't be necessary, either (unless you want to connect to the SI units to monitor remotely, as I'm doing). Frequency shifting via UL1741 should "just happen".

Here are my SB settings:

I've got a SB7.7-1SP-US-41, AC coupled with a pair of SI-6048s. On the SB, under "Grid Monitoring", "Country Standard" is set to "SMA Island mode 60 Hz". I've already fed in 2+ MWh and still have the ability to modify this setting, as far as I can tell.

With SB tied to the AC1 input of the SI, everything works smoothly--frequency ramps up as the battery approaches full charged, and back down again as loads are switched on.

On sunny days the sunny boy pushes 90 amps regardless of what the sunny island is set at and then the sunny boy disconnects.

The SB 6.0 model shouldn't even be capable of pushing 30 amps, let alone 90. Or are you referring to the DC side? If you get your SI connected to wifi or ethernet, you should be able to browse to its IP address, and under "Instantaneous Values", "Status", you should be able to see why it's disconnecting in real time. Or, later, under "Events". What do you see there?

 

[Consumerbot3418]

I'll add that I've not yet seen the SB disconnect, except in one instance where I had a logic error in trying to automate the ESS AC set-point of a Victron system I'd been playing with, and accidentally back-fed too much power. The SB will curtail its output smoothly between 61-62 Hz, but the SI had ramped the frequency all the way up to 63 hertz! The battery was completely full, and the Victron was still backfeeding. SI had nowhere to put the power...

 

[BushMan2000U]

I'm running almost exactly this setup. Don't think @Hedges is off-grid... Do you have a DC Solar trailer, by chance?

I did not need a grid guard code to switch SI to off-grid. RS-485 shouldn't be necessary, either (unless you want to connect to the SI units to monitor remotely, as I'm doing). Frequency shifting via UL1741 should "just happen".

Here are my SB settings:

I've got a SB7.7-1SP-US-41, AC coupled with a pair of SI-6048s. On the SB, under "Grid Monitoring", "Country Standard" is set to "SMA Island mode 60 Hz". I've already fed in 2+ MWh and still have the ability to modify this setting, as far as I can tell.

With SB tied to the AC1 input of the SI, everything works smoothly--frequency ramps up as the battery approaches full charged, and back down again as loads are switched on.


The SB 6.0 model shouldn't even be capable of pushing 30 amps, let alone 90. Or are you referring to the DC side? If you get your SI connected to wifi or ethernet, you should be able to browse to its IP address, and under "Instantaneous Values", "Status", you should be able to see why it's disconnecting in real time. Or, later, under "Events". What do you see there?

It.s on the DC side , Hedges said that it help being set to Island as it has a wider frequency threshold to allow greater voltage fluctuations. Don't have any monitoring other than the sunny portal as of now. Also the Battery is a Big Battery Kong Elite + 17kwh but does not work in closed loop communication with the SI. Looking at Getting a fortress E-Max that does and sell this one.

 

[Consumerbot3418]

If you have sunny portal working, then the inverter has a network connection. It also has a stand-alone Wi-Fi access point. So by connecting to its WiFi or IP address via LAN, you can find the status page and figure out exactly why it’s disconnecting. If it’s not in island mode, that would be step one. Otherwise SI will start to ramp up frequency when the target charge voltage is reached, which is probably why SB is disconnecting.

You shouldn’t really need to have BMS communication working, if you set it up as FLA with appropriate voltage parameters. I’d make sure I got Sunny Island dialed in with appropriate settings before worrying about replacing that battery with something that can communicate with SI, myself.

 

[BushMan2000U]

If you have sunny portal working, then the inverter has a network connection. It also has a stand-alone Wi-Fi access point. So by connecting to its WiFi or IP address via LAN, you can find the status page and figure out exactly why it’s disconnecting. If it’s not in island mode, that would be step one. Otherwise SI will start to ramp up frequency when the target charge voltage is reached, which is probably why SB is disconnecting.

You shouldn’t really need to have BMS communication working, if you set it up as FLA with appropriate voltage parameters. I’d make sure I got Sunny Island dialed in with appropriate settings before worrying about replacing that battery with something that can communicate with SI, myself.

My Sunny Boy only has Hard wire Etherner (NO WLAN ) capability but it does work ,will keep tinkering would really like to be able to keep this Battery instead of starting over.
Thanks for the Input

 

[Hedges]

Another thread same topic:

Sunny Boy and Sunny Island

Looking for some help. I have a new system Completely OFF GRID (Generator back -up )with a sunny boy 6.0US-41 and two sunny island 60/48 inverters. Do i need a grid guard code to set the sunny boy to off grid mode only and is the RS 485 piggy back cards required for both units to communicate...

diysolarforum.com

I didn't notice my name before in the "bell" icon alerts. It doesn't email me. Private message would be most reliable.
Now that we're not using emails I do go through alerts, more likely to see @Hedges

Older Sunny Boys with RS-485 and older interfaces, I have ways to set with password = sum of month/day/year. The new Ethernet based ones I use Grid Guard for some parameters "installer" rather than "user password for others.

I think SB -41 is Ethernet only, can change within 10 operating hours of commissioning. After that, need Grid Guard.

RS-485 not needed for -41, may or may not fit this inverter. I've tried RS-485 in a Sunny TryPower and only saw serial number, no data. Had to use Ethernet.

RS-485 is used on older models, at least up through 5000US. For 10000TLUS I had to use Ethernet/Speedwire to configure. It did support RS-485 (I think) but couldn't configure it using Sunny Boy Control. Turned out it did NOT properly switch between UL-1741 and off-grid when set to "backup". The 5000US did switch when SI communicated over RS-485.

"Island" a.k.a. Offgrid should be better as mentioned. "Rule-21" is supposed to work (maybe not as well). Another member was able to get Grid Guard and change from UL-1741 to Rule-21 for on-grid, hasn't tried SI yet.

 

[Consumerbot3418]

I think SB -41 is Ethernet only, can change within 10 operating hours of commissioning. After that, need Grid Guard.

@Hedges :

My -41 has WiFi, although I finally got around to connecting it via ethernet. I think SMA must have had trouble getting WLAN modules due to COVIDcrisis supply chain issues, but figured it wasn't worth holding up production, and just sold them without?

And I hate to further contradict you, but I have 100+ feed-in hours, and have retained the ability to change country standard, as detailed here--no grid guard required. Not sure if my case is unique somehow.

 

[Hedges]

That is what SMA said. And they said no way to tell whether the Sunny Boy you buy was going to have WiFi or not. But I've seen listings which identify that.

I'm glad you can contradict me on that; maybe you've found the access mode which bypasses Grid Guard. Another guy had to get Grid Guard and then was able to select Rule 21.

 

[Solarisium]

My SB 3.8 US-41 was not shipped with WLAN. It does feature two ethernet ports though and I have connected it to my internet using one of them.
SMA actually ships an additional page explaining that WLAN chip was not available due to shortage of chips during covid19. The SB label however still shows a password for wifi!!

@Hedges :

My -41 has WiFi, although I finally got around to connecting it via ethernet. I think SMA must have had trouble getting WLAN modules due to COVIDcrisis supply chain issues, but figured it wasn't worth holding up production, and just sold them without?

And I hate to further contradict you, but I have 100+ feed-in hours, and have retained the ability to change country standard, as detailed here--no grid guard required. Not sure if my case is unique somehow.

I came up with a short term work around: I am using a small wifi repeater that offers an ethernet port. It’s so small that can fit inside the Sunny Boy chamber and is powered up by L1 and N wires coming from the main breakers panel to the SB. I won’t have instant data during power outages.

Also I have enabled data logging to USB and now collecting generation data in one second intervals. At 30MB CSV file data per day it needs
~11GB free space for one year storage!

 

[Hedges]

I think my Web Box is set to 15 minute intervals, so slow to fill the maximum 2GB SD card, but not much resolution to see what happened when a breaker trips.

Faster logging followed by decimation after a while could give us more details where we need them.

 

[beastman]

Another thread same topic:

Sunny Boy and Sunny Island

Looking for some help. I have a new system Completely OFF GRID (Generator back -up )with a sunny boy 6.0US-41 and two sunny island 60/48 inverters. Do i need a grid guard code to set the sunny boy to off grid mode only and is the RS 485 piggy back cards required for both units to communicate...

diysolarforum.com

I didn't notice my name before in the "bell" icon alerts. It doesn't email me. Private message would be most reliable.
Now that we're not using emails I do go through alerts, more likely to see @Hedges

Older Sunny Boys with RS-485 and older interfaces, I have ways to set with password = sum of month/day/year. The new Ethernet based ones I use Grid Guard for some parameters "installer" rather than "user password for others.

I think SB -41 is Ethernet only, can change within 10 operating hours of commissioning. After that, need Grid Guard.

RS-485 not needed for -41, may or may not fit this inverter. I've tried RS-485 in a Sunny TryPower and only saw serial number, no data. Had to use Ethernet.

RS-485 is used on older models, at least up through 5000US. For 10000TLUS I had to use Ethernet/Speedwire to configure. It did support RS-485 (I think) but couldn't configure it using Sunny Boy Control. Turned out it did NOT properly switch between UL-1741 and off-grid when set to "backup". The 5000US did switch when SI communicated over RS-485.

"Island" a.k.a. Offgrid should be better as mentioned. "Rule-21" is supposed to work (maybe not as well). Another member was able to get Grid Guard and change from UL-1741 to Rule-21 for on-grid, hasn't tried SI yet.

Great information on the offgrid /backup mode. It sounds like the Rs485 connection to the SI's from the SB's are modifying the operating condition or sending a specific command to bring up the SB's when in off-grid mode over RS485 and this will not work natively for UL-1741. I am looking at doing the solark 15k or 18k eg4 this summer due to peak-shaving working natively which will pay for the other inverter in a few years in California. I am ac coupled w/ a 200a panel some 250' away and want to keep my SB7000US and SB6000US in place and sell the Sunny Islands at this point instead of running a ton of copper 250' away to the mppt connections. Sounds like off-grid mode is not going to work natively with any of the RS485 SB inverters unless they are paired to a few SI's. Unless there is a newer firmware to solve this, the SB's are only ever going to work on-grid/off-grid properly with a pair of SI's.

 

[Hedges]

Older SB like yours have UL-1741 or Island mode, also "backup" which has them switch between UL-1741 (tighter limits and active anti-islanding) and Island (looser limits and no anti-islanding) when SI sends RS-485 signal.

Set to UL-1741, they will work with a grid-forming inverter like any other UL-1741 non -SA, non Rule-21 inverter. Their anti-islanding doesn't keep them from working with Sunny Island (they way we hear Enphase IQ8 seems to with Sol-Ark and others.)

You can change limits, for instance UL-1741 standard frequency limits are narrower than UL-1741-SA, and can be changed. In particular, SI will spend some time at 59 Hz (if that feature not disabled), and wider limits prevents SB from disconnecting.

SB with SolArk should work, but will switch off when frequency shifts. If you have enough DC coupled PV for SolArk to vary power harvesting, that should be OK.

If set to Island mode, SB would do frequency-watts. But it would not do anti-islanding; it would rely on battery inverter to protect the grid. That functions, but due to my concern of battery inverter getting its relays welded shut I don't do that or recommend it.

I have not figured out what RS-485 signal commands the on/off grid switching. I've never captured it with a scope, although I could see other communications which I used to read/set SB parameters.

 

[beastman]

Older SB like yours have UL-1741 or Island mode, also "backup" which has them switch between UL-1741 (tighter limits and active anti-islanding) and Island (looser limits and no anti-islanding) when SI sends RS-485 signal.

Set to UL-1741, they will work with a grid-forming inverter like any other UL-1741 non -SA, non Rule-21 inverter. Their anti-islanding doesn't keep them from working with Sunny Island (they way we hear Enphase IQ8 seems to with Sol-Ark and others.)

You can change limits, for instance UL-1741 standard frequency limits are narrower than UL-1741-SA, and can be changed. In particular, SI will spend some time at 59 Hz (if that feature not disabled), and wider limits prevents SB from disconnecting.

SB with SolArk should work, but will switch off when frequency shifts. If you have enough DC coupled PV for SolArk to vary power harvesting, that should be OK.

If set to Island mode, SB would do frequency-watts. But it would not do anti-islanding; it would rely on battery inverter to protect the grid. That functions, but due to my concern of battery inverter getting its relays welded shut I don't do that or recommend it.

I have not figured out what RS-485 signal commands the on/off grid switching. I've never captured it with a scope, although I could see other communications which I used to read/set SB parameters.

Sounds like I need to do PV direct to the solark. I guess the SB could be setup for off-grid mode w/ frequency shift but like you said you were worried the contacts get welded on the main inverter in some strange scenario. I don't think it's much different however in comparison if the sunny island had it's contacts welded as the sb sits behind it, but then in a grid-down scenario you would not have the sb putting out power as long as the rs-485 connection is setup between the two. Big PIA as the cost to upgrade wiring to the solark direct will cost more than buying a used grid-tied inverter w/ frequency shifting due to the wire run length and conduit.

 

[Hedges]

I am concerned about contacts welding in Sunny Island. People here have said that happens. That is why I don't want to take SMA America's recommendation (given in a video) to set Sunny Boy to off-grid. Instead I follow what SMA Germany said in writing, in their documents: Set Sunny Boy to Backup.

RS-485 will not stop Sunny Boy from delivering power. All it does is says when to switch from UL-1741 parameters to off-grid. In the event contacts weld and Sunny Island can't disconnect from grid, I presume Sunny Island won't tell Sunny Boy to do that.

I might be less worried about the 200A contactor in SolArk welding, but I don't know.

You can pick up used GT PV inverters that do frequency-watts, and does anti-islanding. As you say, that could be cheaper and more convenient.
But I don't know how well SolArk supports frequency-shift - better check into that. If it won't do it smoothly for frequency-watts, just raises to knock GT PV offline, the one you've got could be good enough.

 

[beastman]

sounds like I will need to test this out. Ordered my solark 15k today at watts247 for less than $7k. Will be here in a few weeks. The amount of time/work/labor saved with the solark in my situation is huge and permitting is going to be easy. With the sunny islands I was going to need some additional transfer switches, 250' wire run of at least 125a rated wire (ac) and manual intervention would still be needed. Peak shaving was possible with some hackery. The only real drawback is the sunny island inverters supporting independent legs vs. the solark needing power to be within 8kw or so. Peak draw for 10 seconds is up to 24000 watts. My sunny islands will be for sale here shortly once everything is completed, they are both 5.5k (si5048) models and have everything installed. Not sure what they are worth now (somewhere between $1700 and $2200) each is what the market looks like. The big reason to get this done was to save $300 a month this summer on peak shaving and get the 30kw of SOK's installed with the main inverter in a weekend. I think both the SI's and solark are fairly proven reliable in the marketplace at this point.

I guess either way if a contactor failed on the solark (e.g. welded) and the inverter was still sending power in off-grid mode, not sure if there is another method for the solark to disconnect internally or not. I have a generator to install with this setup too so this will be interesting to have the whole setup done.

If this setup works well I will likely use my other SB6000US to drive another 7k watts or so over AC through the solark with some cheap panels on a ground mount.

 

[Hedges]

Also consider changing SB frequency-watts setting to ramp down from 60 Hz to 60.5 Hz. I don't know if that would function in UL-1741 mode, but if it does you'll have smooth regulation and anti-islanding.