shadowmaker
Solar Addict
Only main fuse size limited, not how many kWhs I sell. My four inverters are capable for 54kW, main fuse is little bigger.
My 44kW vertical and bifacial set in Finland.
- Thread starter shadowmaker
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Did you consider a simpler mounting system? The simpler I can think of would be two aluminum U-channels: 1 at the bottom and 1 at the top, "bracing" the panels. Maybe the bottom one could be sitting atop another aluminum 2x4 which could serve to hold the weight and for cable management...
shadowmaker
Solar Addict
I'm sure this could have been done better/cheaper/stronger. I'm not an engineer. It was just something that came to my mind. It has been holding for over a year now, so can't be sad. BUT it needs to hold for 20-30 years, so can't tell yet if my idea was good or not. All I know it is very rigid/strong construction with such little material used and removing one panel would be easy if needed.
I still think it's one of the smartest ideas I've seen on the forum, and better than anything the rest of us have come up with, for far-north solar. Heck, I'm resorting to using the side of the barn and the gambrel roof (once they get the darn thing built, which is the current battle). Good on ya, man. We're a couple-dozen pages into the thread, and it's still one I go to for every post. Helped to inspire me to go ahead with off-grid solar here in the northern US.
shadowmaker
Solar Addict
shadowmaker
Solar Addict
On a more serious note we had an extraordinary May here. Usually one or two over +25C days and now something like 15 and full sun every day. On the good side May production was 8,1MWh while PVWatts predicts 6,1MWh. Averaged 260kWh/day. Didn't think it is even possible.
On the bad side this kind of heat makes thunderstorms and few days ago returning late in the evening from summer cottage for a nice smoke sauna and swim I noticed my close neighbor's outbuilding was on fire and called fire department. There was nothing to do anymore and the building burned to the ground, literally. Fortunately there was also heavy rain so nothing else was harmed. It's an old small farm servicing only as summer cottage these days and no one was there at the time, but still a big unfortunate loss to them.
On the bad side this kind of heat makes thunderstorms and few days ago returning late in the evening from summer cottage for a nice smoke sauna and swim I noticed my close neighbor's outbuilding was on fire and called fire department. There was nothing to do anymore and the building burned to the ground, literally. Fortunately there was also heavy rain so nothing else was harmed. It's an old small farm servicing only as summer cottage these days and no one was there at the time, but still a big unfortunate loss to them.
I know. It's horrible - way to hot!
houseofancients
Solar Wizard
Send it here please..
Been nothing but rain and cloudiness here since Feb...
I don’t know how your ancestors survived without air-conditioning.
shadowmaker
Solar Addict
True. I got everything to start building my next array of panels, but not with this heat. Also there has been so much production lately that I can just focus on other things just now.
shadowmaker
Solar Addict
They were tough like six inch nails, but we are more like latte people with raised pinky finger nowadays. Me included.
shadowmaker
Solar Addict
Seems there is a problem (or just annoying me) with getting my LFPs to top balance themselves. Unlike Andy @Off-Grid-Garage reported, these shitty internal 50mA passive balancers are eventually balancing out my batts. Slowly but steadily. Most certainly it has all to do my batts being full for ~10-15 hours almost every day now, so to my surprise even small balancing current seems to be enough. First my 3x 5kWh wall batts got balanced and now 4/6 of my 10kWh rack batts are balanced too. Those two that haven't have different situation because some low voltage cells in them. This means that 50mA balancer needs to burn excess from 14-15 cells to level up those low ones, so it is going to take some time. I could open those two up and install Neeys on them or just charge those few low cells individually. But it is already obvious that they are going to balance out if they just get enough time to do so, so not going to bother.
Problem (annoying thing) with top balanced batts is closed loop communication or at least it is with my setup. Closed loop tells to charge with 56,5V (3,53V/cell) so "full battery" is never triggered as it happens only when one cell goes over 3,6V. This means my capacity % starts to drift. Instead being full at 56,5V they soon start saying capacity is 99% and then 98% and then... It takes 3-4 days to get down 97% and then I just adjust full capacity manually using BMS tool. It only takes few minutes to do, but it is annoying. I don't seem to find any setting using BMS tool to fix this so I have asked batt manufacturer what to do but haven't got answer yet. Let's see what they suggest.
Problem (annoying thing) with top balanced batts is closed loop communication or at least it is with my setup. Closed loop tells to charge with 56,5V (3,53V/cell) so "full battery" is never triggered as it happens only when one cell goes over 3,6V. This means my capacity % starts to drift. Instead being full at 56,5V they soon start saying capacity is 99% and then 98% and then... It takes 3-4 days to get down 97% and then I just adjust full capacity manually using BMS tool. It only takes few minutes to do, but it is annoying. I don't seem to find any setting using BMS tool to fix this so I have asked batt manufacturer what to do but haven't got answer yet. Let's see what they suggest.
42OhmsPA
What's in a title?
Isn't there a setting to adjust the cell full and / or the pack full voltage in the BMS software? This would let you charge to a lower voltage.
shadowmaker
Solar Addict
I'm pretty sure there is but can't find it. Maybe the password they gave me before is only for restricted access and I need some kind of master password to change closed loop related parameters? I have noticed a table of parameters that only exists for a fraction of a second when I go to certain page on my BMS tool. It disappears so quickly that I can't see what's in there. I bet they won't give me that master password, but they might give me new file to update these batts once again.
I don't see the point to charge my batts any higher than current 56,5V (3,53V/cell) and I think even 55,0V (~3,44V) would be just fine and high enough to decent enough top balance. With these cheapo batteries I'm not that sure that even "perfect" top balance will help with bottom balance. I bet my cells aren't capacity matched so when discharged it's more up to chance than how they are top balanced.
shadowmaker
Solar Addict
I think my batts have Topband BMS in them, but not sure. I translated some Chinese from BMS tool they gave me and it came up with that name. BMS itself has no labeling to tell anything about its origin. I know Topband is used in Ruixu batteries, but other than that it seems rare.
shadowmaker
Solar Addict
Two new 10kWh batts arrived.
First one.
Second one.
5117mV is impossible and all three faults are similar so I'm betting there are loose/faulty voltage detection/balancer wires. Need to open up these to see. This is what you get going for cheapest. Oh well, I don't mind opening them up and installing decent balancers while doing that.
First one.
Second one.
5117mV is impossible and all three faults are similar so I'm betting there are loose/faulty voltage detection/balancer wires. Need to open up these to see. This is what you get going for cheapest. Oh well, I don't mind opening them up and installing decent balancers while doing that.
Brucey
Solar Wizard
yeah hopefully just loose sense wires. I have a random “gokwh” 5 kWh showing up tomorrow hopefully it does better but will grab internal shots for science.
shadowmaker
Solar Addict
Next week I have scheduled to install 15,4kWp more panels. 550W monopanels on shed roof this time, so have no idea how it's going to go. I'm pretty sure I can manage that, but at some point I need to install my FIL's 6,6kWp set of same panels on his high roof with brittle roof tiles you can't walk on. That's going to be scary.
shadowmaker
Solar Addict
Got time to open up the other batt and as suspected one sense lead had bad solder. Wire was only held by glue.
Funny thing is that these new batts look identical to my old set outside but inside have changed. My older rack batts are 2P16S with blade type cells (terminals on opposite ends) with non-welded busbars as these new ones are plain 16S with welded busbars. Just opened the lid and removed yellow plastic and everything is easy to access which was nice.
There is downsides too. Those aluminum busbars have laser welded small inserts where sense leads are soldered and then secured with silicone glue. I don't think that's wise as manufacturing level way to connect those cables. Not fast, not secure.
After resolderig that one bad connection I installed wiring for Neey balancer too. Used the same stupid soldering type connection with glue but decided that for the next one I should come up with a better/easier/more secure way to do this. I'm thinking small drill hole in middle of busbar with small screw and glue to secure. Ring terminal for Neey wire.
Now I need to just drill small hole to front face to get Neey connectors outside. Not going to look pretty, but practicality before beauty.
Funny thing is that these new batts look identical to my old set outside but inside have changed. My older rack batts are 2P16S with blade type cells (terminals on opposite ends) with non-welded busbars as these new ones are plain 16S with welded busbars. Just opened the lid and removed yellow plastic and everything is easy to access which was nice.
There is downsides too. Those aluminum busbars have laser welded small inserts where sense leads are soldered and then secured with silicone glue. I don't think that's wise as manufacturing level way to connect those cables. Not fast, not secure.
After resolderig that one bad connection I installed wiring for Neey balancer too. Used the same stupid soldering type connection with glue but decided that for the next one I should come up with a better/easier/more secure way to do this. I'm thinking small drill hole in middle of busbar with small screw and glue to secure. Ring terminal for Neey wire.
Now I need to just drill small hole to front face to get Neey connectors outside. Not going to look pretty, but practicality before beauty.
shadowmaker
Solar Addict
First batt ready with Neey balancer.
Started panel install. 28 x 550W = 15,4kWp.
Started panel install. 28 x 550W = 15,4kWp.
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