Roland, even if you successfully repair the other inverters, the cause of the failures is still not resolved. Have you firmly established what the root cause of the problem is? Is the root cause due to the Thai power utility company mains grid Voltage surges? Is the root cause due to the collapsing magnetic field of the AC inductor coils? Can you use a microcontroller read and write device to be able to copy the program from a good MCU (from one of your other identical inverters), then write the program onto a replacement ordered bare MCU to still be able to use in this inverter that has a shorted MCU? Surely you can use some kind of USB powered MCU read and write device to be able to copy programs and transfer into blank MCU. Excuse my lack of understanding and jargon terminology.
Hi. Sure, the root cause of all failures was the unreliable grid here in Thailand. What especially is angering me are the short interruptions cause by switching inside the local high voltage grid. This is not just killing the inverters. It is as well killing some other appliances from time to time. As you say, the interruptions are causing surges in coils which then overlay with the returning sinewave and amplify in attitude. I cannot eliminate those issues with the grid. What I have done is, I have ordered voltage protection relays for each phase going to the SUN inverters. The relays will disconnect the line if the voltage drops down for more then 0.1sec, and only reconnect after 60sec if the voltage was stable. This will allow the devices to safely shut down and remove all potentials inside, and later just stably restart. This board with the shorted MCU, I see as an unusual case. As the surge was external and just found a way into the system. Then it found a path to off-load. Unfortunately that path left total destruction, while the final component was the MCU. I don't think it is so easy to copy a MCU. At least it would require some equipment which will have its cost as well. This board shall now just be a donor for others if necessary. But still I do hope that the most recent and soon implemented changes in system protection will help to avoid this situations in future. Repair is the best and cheapest I can do now and if this doesn't help in the long run, I will have to install a better inverter there.
@@RolandW_DIYEnergyandMore I was of the understanding that you use an ATS (Automatic Transfer Switch), for whenever the mains grid is supplying power or not. Perhaps the rating of the ATS switch Voltage tolerance and speed of disconnect is not good enough. Would a better quality ATS be a solution to minimize unwanted surges? The last time I looked into ATS devices, there does not seem to be many to choose from on the market here in Australia.
@@Matthew_Australia no, the ATSs are doing something completely different. They are on the off-grid/hybrid systems and are primarily on source Inverter and normally stay there without ever switching as the inverters are taking care of a missing grid by either anyways always being, or going off-grid when there is no grid. The ATS would switch to grid as secondary source when the inverter fails. All other grid-tied inverters, of which kind the SUN inverters are as well, do not have any ATS. When the grid fails, those inverters go into anti-islanding protection mode. Now, a standard grid-tied inverter runs on DC from the PV and when the AC goes away, it just times-out until AC is back and waits another 60 sec to reconnect. The SUN1000/2000GTIL runs on AC. So when the AC is gone, the Inverter goes dead and as soon AC is back it immediately powers up and very quickly reconnects to grid again. This is in my opinion a very bad solution. And short AC interruptions makes the inverter probably get caught in a weird startup situation, where maybe all parts of the inverter have not yet been off yet... Thats just my theory though ;)
@@RolandW_DIYEnergyandMore I don't know much about grid-tied inverters, as I live off grid and only use off-grid hybrid AIO inverter chargers. Perhaps a dedicated UPS (Uninterrupted Power Supply) between the grid-tied inverter and mains can be used to alleviate brown outs and Voltage surges, with an alarm. The mains power is fed into the UPS, and then the power from the UPS is fed into the inverter.
@@Matthew_Australia well yeah. Grid-tied inverters must follow the grid. If the grid goes down, they have to disconnect by whatever means. It would be illegal to keep it artificially connected (that's what grid-DIY-haters always say...we are killing all the linemen). And of course, a grid -tied inverter is always trying to push its available energy onto the grid. That would be difficult if there is an UPS in-between. As I said, a normal style grid-tied inverter doesn't have any problems with any sort of outage (long or short), it's just the weird architecture of the SUN-GTILs which seem to be at fault. The voltage protection relays should fix the issue by removing those short interruptions at my place. And other types of surges must be dealt with by the SPDs
A truly useful use for alcohol rather than using it as a solvent to dissolve relationships, employment and health 🙂👍
Drinking IPA would kill you quite quickly :))
Nice try but sometimes the bear wins so it goes into the part drawer lol
A 2:1 would be a nice result for me. Let's just not lose the game by 0:3 :))
Roland, even if you successfully repair the other inverters, the cause of the failures is still not resolved. Have you firmly established what the root cause of the problem is? Is the root cause due to the Thai power utility company mains grid Voltage surges? Is the root cause due to the collapsing magnetic field of the AC inductor coils?
Can you use a microcontroller read and write device to be able to copy the program from a good MCU (from one of your other identical inverters), then write the program onto a replacement ordered bare MCU to still be able to use in this inverter that has a shorted MCU? Surely you can use some kind of USB powered MCU read and write device to be able to copy programs and transfer into blank MCU.
Excuse my lack of understanding and jargon terminology.
Hi. Sure, the root cause of all failures was the unreliable grid here in Thailand. What especially is angering me are the short interruptions cause by switching inside the local high voltage grid. This is not just killing the inverters. It is as well killing some other appliances from time to time. As you say, the interruptions are causing surges in coils which then overlay with the returning sinewave and amplify in attitude. I cannot eliminate those issues with the grid.
What I have done is, I have ordered voltage protection relays for each phase going to the SUN inverters. The relays will disconnect the line if the voltage drops down for more then 0.1sec, and only reconnect after 60sec if the voltage was stable. This will allow the devices to safely shut down and remove all potentials inside, and later just stably restart.
This board with the shorted MCU, I see as an unusual case. As the surge was external and just found a way into the system. Then it found a path to off-load. Unfortunately that path left total destruction, while the final component was the MCU.
I don't think it is so easy to copy a MCU. At least it would require some equipment which will have its cost as well. This board shall now just be a donor for others if necessary.
But still I do hope that the most recent and soon implemented changes in system protection will help to avoid this situations in future. Repair is the best and cheapest I can do now and if this doesn't help in the long run, I will have to install a better inverter there.
@@RolandW_DIYEnergyandMore I was of the understanding that you use an ATS (Automatic Transfer Switch), for whenever the mains grid is supplying power or not. Perhaps the rating of the ATS switch Voltage tolerance and speed of disconnect is not good enough. Would a better quality ATS be a solution to minimize unwanted surges?
The last time I looked into ATS devices, there does not seem to be many to choose from on the market here in Australia.
@@Matthew_Australia no, the ATSs are doing something completely different. They are on the off-grid/hybrid systems and are primarily on source Inverter and normally stay there without ever switching as the inverters are taking care of a missing grid by either anyways always being, or going off-grid when there is no grid. The ATS would switch to grid as secondary source when the inverter fails.
All other grid-tied inverters, of which kind the SUN inverters are as well, do not have any ATS. When the grid fails, those inverters go into anti-islanding protection mode. Now, a standard grid-tied inverter runs on DC from the PV and when the AC goes away, it just times-out until AC is back and waits another 60 sec to reconnect.
The SUN1000/2000GTIL runs on AC. So when the AC is gone, the Inverter goes dead and as soon AC is back it immediately powers up and very quickly reconnects to grid again. This is in my opinion a very bad solution. And short AC interruptions makes the inverter probably get caught in a weird startup situation, where maybe all parts of the inverter have not yet been off yet...
Thats just my theory though ;)
@@RolandW_DIYEnergyandMore I don't know much about grid-tied inverters, as I live off grid and only use off-grid hybrid AIO inverter chargers.
Perhaps a dedicated UPS (Uninterrupted Power Supply) between the grid-tied inverter and mains can be used to alleviate brown outs and Voltage surges, with an alarm. The mains power is fed into the UPS, and then the power from the UPS is fed into the inverter.
@@Matthew_Australia well yeah. Grid-tied inverters must follow the grid. If the grid goes down, they have to disconnect by whatever means. It would be illegal to keep it artificially connected (that's what grid-DIY-haters always say...we are killing all the linemen). And of course, a grid -tied inverter is always trying to push its available energy onto the grid. That would be difficult if there is an UPS in-between. As I said, a normal style grid-tied inverter doesn't have any problems with any sort of outage (long or short), it's just the weird architecture of the SUN-GTILs which seem to be at fault. The voltage protection relays should fix the issue by removing those short interruptions at my place. And other types of surges must be dealt with by the SPDs