I have a really crazy setup.
My "main" system is Outback power, 2 Radian 8048 inverters, 5 old MX60 charge controllers, 32 280W Chaori panels (4 sets of 8) and 10 285W GCL panels for a total of 11,810W . It's backed up with a propane generator and 4000 gallons of propane on site.
I decided to expand, so bought 648 of the GCL 285W panels (long story). Due to costs of hybrid system components, I figured I'd do an A/C coupled grid tie inverter. Then I though more about it and wondered why can't I just do a second system. One hybrid system with generator backup, and one direct grid tie. If power goes out, chances are my 11.8kw is enough to survive on and the grid tie panels can go silent.
So.....
Grid voltage 240V. Hybrid system wants to sell, it has to push the power at more than that, so it decides to go to 248V.... Grid tie system sees 248V, needs to push higher, so sells at 250V. Outback sees 250V, goes to 252V, etc, etc, etc, etc. Voltage high for the day is recorded at 262V, and I miss an estimated 25kw of power from the SMA SB6000TL-22 because it has shut down.
I'm getting the 262V max reading from the Outback system. Today, high volt 262V, low volt 241V.
Now the confusing part, because this doesn't happen all the time. Most days, both systems play fine together and I get full expected numbers.
The SMA manual says nominal AC input voltage from 211 to 264V.
The SMA fault when it is down is 1501 "Reconnection Fault Grid" which is described as "The changed country data set or the value of a parameter you have set does not correspond to the local requirements. The inverter cannot connect to the utility grid. Corrective Measures: Ensure that the country data set has been configured correctly. Check the setting of the rotary switches A and B or select the parameter Set Country standard and check the value.
So, theoretically, the error actually has nothing to do with the voltage climb. It's only experience that tells me that it is related.
OK. Next diagnostic step is to spend $250 on the remote control breaker set up for the Radians and hook this SMA up as an A/C coupled inverter. That will negate the A/C input voltage question.
But, that only allows me to fix this immediate issue (assuming my assumptions are correct, lol). If I want to increase the system size exponentially (target is 80kw), then I cannot do it through A/C coupling. I will need to run a direct grid tie system beside the hybrid system, or spend $50,000 on additional equipment and batteries.
I guess this is the question. At what point does the voltage difference not matter. That is, if the grid is sitting at 244V, and my system comes on-line and starts pushing 248V to the grid, what if my neighbor has a system? Does his end up pushing 252V, which then forces mine to push 256V, etc, etc, until one of us shuts down? There are two reasons I ask this.
1. My area has horrible voltage control. I have had to call out the electric company twice in the last few months for voltage issues. We have seen has high as 283V. Geeze the reacted quick on that one. They were here within hours and while they won't tell me what they did, they dropped the voltage to the 250V range.
2. I have the ability to have the grid tie system feed in about 280 linear feet away from the hybrid system. At what point does the voltage normalize when feeding back. Load will effect this, but fact is, if there's 10 houses feeding into the grid on any given street, the voltages are not going to climb into the stratosphere, and I bet none of those systems are going to shut off due to voltage. There has to be some point where voltage normalizes over distance, with load.
OK, enough rambling. Anyone care to comment?
My "main" system is Outback power, 2 Radian 8048 inverters, 5 old MX60 charge controllers, 32 280W Chaori panels (4 sets of 8) and 10 285W GCL panels for a total of 11,810W . It's backed up with a propane generator and 4000 gallons of propane on site.
I decided to expand, so bought 648 of the GCL 285W panels (long story). Due to costs of hybrid system components, I figured I'd do an A/C coupled grid tie inverter. Then I though more about it and wondered why can't I just do a second system. One hybrid system with generator backup, and one direct grid tie. If power goes out, chances are my 11.8kw is enough to survive on and the grid tie panels can go silent.
So.....
Grid voltage 240V. Hybrid system wants to sell, it has to push the power at more than that, so it decides to go to 248V.... Grid tie system sees 248V, needs to push higher, so sells at 250V. Outback sees 250V, goes to 252V, etc, etc, etc, etc. Voltage high for the day is recorded at 262V, and I miss an estimated 25kw of power from the SMA SB6000TL-22 because it has shut down.
I'm getting the 262V max reading from the Outback system. Today, high volt 262V, low volt 241V.
Now the confusing part, because this doesn't happen all the time. Most days, both systems play fine together and I get full expected numbers.
The SMA manual says nominal AC input voltage from 211 to 264V.
The SMA fault when it is down is 1501 "Reconnection Fault Grid" which is described as "The changed country data set or the value of a parameter you have set does not correspond to the local requirements. The inverter cannot connect to the utility grid. Corrective Measures: Ensure that the country data set has been configured correctly. Check the setting of the rotary switches A and B or select the parameter Set Country standard and check the value.
So, theoretically, the error actually has nothing to do with the voltage climb. It's only experience that tells me that it is related.
OK. Next diagnostic step is to spend $250 on the remote control breaker set up for the Radians and hook this SMA up as an A/C coupled inverter. That will negate the A/C input voltage question.
But, that only allows me to fix this immediate issue (assuming my assumptions are correct, lol). If I want to increase the system size exponentially (target is 80kw), then I cannot do it through A/C coupling. I will need to run a direct grid tie system beside the hybrid system, or spend $50,000 on additional equipment and batteries.
I guess this is the question. At what point does the voltage difference not matter. That is, if the grid is sitting at 244V, and my system comes on-line and starts pushing 248V to the grid, what if my neighbor has a system? Does his end up pushing 252V, which then forces mine to push 256V, etc, etc, until one of us shuts down? There are two reasons I ask this.
1. My area has horrible voltage control. I have had to call out the electric company twice in the last few months for voltage issues. We have seen has high as 283V. Geeze the reacted quick on that one. They were here within hours and while they won't tell me what they did, they dropped the voltage to the 250V range.
2. I have the ability to have the grid tie system feed in about 280 linear feet away from the hybrid system. At what point does the voltage normalize when feeding back. Load will effect this, but fact is, if there's 10 houses feeding into the grid on any given street, the voltages are not going to climb into the stratosphere, and I bet none of those systems are going to shut off due to voltage. There has to be some point where voltage normalizes over distance, with load.
OK, enough rambling. Anyone care to comment?
Comment