Battery B is taking shape, just need to connect up the balance cables tomorrow and it should be alive.
Ronski's Solar & battery DIY build with whole house backup
- Thread starter Ron-ski
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Battery B is complete and alive.
Only problem now is I can't access the BMS for Battery A, I setup the new JK BMS, changed the pairing password and the settings password, went back to the other BMS and it asked me to pair it, every time I try, no matter what pin number I use it says it failed to pair, even checked my notes which said the pairing password was 1234 but that doesn't work either. Downloaded JK BMS App version 4.8.4.132 and still can't access the first BMS.
Only other thing I noticed was that battery B was only discharging about half the current of battery A, I think it just needs to fully absorb, can't find/think of any other reason why there's such a difference.
Only problem now is I can't access the BMS for Battery A, I setup the new JK BMS, changed the pairing password and the settings password, went back to the other BMS and it asked me to pair it, every time I try, no matter what pin number I use it says it failed to pair, even checked my notes which said the pairing password was 1234 but that doesn't work either. Downloaded JK BMS App version 4.8.4.132 and still can't access the first BMS.
Only other thing I noticed was that battery B was only discharging about half the current of battery A, I think it just needs to fully absorb, can't find/think of any other reason why there's such a difference.
Hopefully just a glitch, it's the BMS access problem that's annoying.
No rodent protection, perhaps I should shut the cat in there. Apart from putting out some poison, which will also attract rodents there's not a lot I can do.
No rodent protection, perhaps I should shut the cat in there. Apart from putting out some poison, which will also attract rodents there's not a lot I can do.
I had to side load the new app - the one on Playstore is well out of date, I didn't try rebooting though. May try a different phone, just in case. The default pairing password is 1234 isn't it?
Apparently it is possible too get a temporary password, which works for 30 minutes, unless this is a pre-existing password no idea how they set it up as the BMS is not internet connected.
Apparently it is possible too get a temporary password, which works for 30 minutes, unless this is a pre-existing password no idea how they set it up as the BMS is not internet connected.
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Doh! You are correct, no idea why I thought the one I downloaded was newer, just uninstalled and installed the Play Store version. Not that it will make any difference, as I did originally have that.
PS That old app works with the new BMS.
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I haven't tried the Ruuvitags yet, just the wired temperature sensors so far.
Bizarrely tonight I can access BMS A, it doesn't ask for a pairing password, but I've tried changing the password and it keeps telling me the old password is wrong, so looks like I'll still need a temporary password. I've currently installed the app on my tablet, and can access Battery B BMS via that.
I charged the batteries with 17.32 kWh in the off peak period - I set charging at 104A total - could go to 140A, but I don't think I need to, and I want to be sure everything was working OK prior to pushing 140A through the system.
Tonight I discharged around 13.16 kWh between 16:00 and 19:00, both batteries pretty much supplied the same current, some minor variation, but nothing to worry about, both pretty much showed the same SOC on their BMS displays as well, which matched Victrons SOC.
I checked the system for hot connections whilst force discharging tonight, the warmest spot was the busbar either side of my Victron rotary isolator, which was about 40c, this was with 140A running through it. These are rated for 275A continuous so it shouldn't be getting warm, so perhaps I'll have to pull it off and check the connections. Actually it seems perfectly normal https://community.victronenergy.com...itch-gets-too-hot-would-victron-switch-o.html
I charged the batteries with 17.32 kWh in the off peak period - I set charging at 104A total - could go to 140A, but I don't think I need to, and I want to be sure everything was working OK prior to pushing 140A through the system.
Tonight I discharged around 13.16 kWh between 16:00 and 19:00, both batteries pretty much supplied the same current, some minor variation, but nothing to worry about, both pretty much showed the same SOC on their BMS displays as well, which matched Victrons SOC.
I checked the system for hot connections whilst force discharging tonight, the warmest spot was the busbar either side of my Victron rotary isolator, which was about 40c, this was with 140A running through it. These are rated for 275A continuous so it shouldn't be getting warm, so perhaps I'll have to pull it off and check the connections. Actually it seems perfectly normal https://community.victronenergy.com...itch-gets-too-hot-would-victron-switch-o.html
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My electrician is finally booked for next Thursday to replace the consumer unit, and sign off on the electrics they did for the solar install.
I also finally managed to get a temporary code from JK BMS via the Aliexpress store, what a pain that was given the time difference and having to work, and apparently the code only works for 15 minutes, but its done, and I was able to reset the pairing code.
I also finally managed to get a temporary code from JK BMS via the Aliexpress store, what a pain that was given the time difference and having to work, and apparently the code only works for 15 minutes, but its done, and I was able to reset the pairing code.
Consumer unit was replaced just over a week ago, there were a couple of issues, kitchen lighting circuit was tripping the RCBO, and one of the rings didn't have continuity on the live circuit, well it did then didn't then it did - turned out to be an HR fault.
I traced the kitchen light fault to where an earth wire had crossed the neutral inside the outer sheath, and when the transformer clamp was tightened over time it had forced the earth to cut into the neutral causing it to make a circuit.
The ring fault I traced to a bad connection in the back of a double socket, luckily it was the forth one I checked.
Electrician came back yesterday, and all happy, so should receive the sign off soon.
I traced the kitchen light fault to where an earth wire had crossed the neutral inside the outer sheath, and when the transformer clamp was tightened over time it had forced the earth to cut into the neutral causing it to make a circuit.
The ring fault I traced to a bad connection in the back of a double socket, luckily it was the forth one I checked.
Electrician came back yesterday, and all happy, so should receive the sign off soon.
I've actually been doing some more work on the battery system, need to get my battery heating sorted out.
I jerry rigged the system up over the weekend, just to get one working, to see how it worked and how it needed to go together.
You can see battery A warmed up a little around midday, so it does work.
I also need to get some polycarbonate sheets, to make a cover for the batteries, this will also help keep some heat in as well.
I jerry rigged the system up over the weekend, just to get one working, to see how it worked and how it needed to go together.
You can see battery A warmed up a little around midday, so it does work.
I also need to get some polycarbonate sheets, to make a cover for the batteries, this will also help keep some heat in as well.
@flea.rider The heat source is already built in (hence I was testing it in my post above - I just hadn't done the electrical side), the base plate for the cells is 10mm thick aluminium (effectively a heat spreader plate), stuck to the underside of this is two 24v head pads wired in series, so they can be powered by 48v.
The Victron Cerbo has built in relays, but they are only rated for about 1A at the voltages I'm using, so I use that to drive a solid state relay to switch the 48v to the heater pads.
I don't want to wrap the cells in anything flammable, so I'll make a case out of polycarbonate, and that should keep the heat in, if they do get a little cold then I'll look at adding some insulation, but space is very tight.
The Victron Cerbo has built in relays, but they are only rated for about 1A at the voltages I'm using, so I use that to drive a solid state relay to switch the 48v to the heater pads.
I don't want to wrap the cells in anything flammable, so I'll make a case out of polycarbonate, and that should keep the heat in, if they do get a little cold then I'll look at adding some insulation, but space is very tight.
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I'm still hiding, and I still haven't added it all up yet, I know roughly and it was reassuringly expensive 
That's an average of around 16 kWh a day, background usage is around 500w, that straight away is 12 kWh a day. There is a server running 24/7 (consumes on average 226w), 2 fridges freezers, various networking equipment and other everyday stuff. Oven is electric, we watch TV, use computers etc.
Personally I blame the Mrs, she's always making tea
Seriously though, compared to some its low, others its high, so I'd say slightly above average usage.
Personally I blame the Mrs, she's always making tea
Seriously though, compared to some its low, others its high, so I'd say slightly above average usage.
You sure you only consume 2 kWh a year???? I'm sure you've got something wrong there!
According to Ofgem the average flat or 1 bedroom house consumes 1800 kWh a year, the average 4+ bedroom house which we come into is 4100 kWh. Going by what I've seen posted on here 6000 kWh a year is quite low compared to some.
@Megahackerd If you run a router 24/7/365 that will use roughly 7.5w, that's 65.7 kWh a year, now you're going to be running a fridge as well, as various other stuff, you see why I don't think your using 2 kWh a year?
2 KW of panels is not going to produce a lot, probably around 2000kWh a year, even if it completely covered you're background usage, there would still be the hours of darkness.
As @Welshman has suggested, its likely to 2000 kWh or 2 MWh, which is far more believable.
2 KW of panels is not going to produce a lot, probably around 2000kWh a year, even if it completely covered you're background usage, there would still be the hours of darkness.
As @Welshman has suggested, its likely to 2000 kWh or 2 MWh, which is far more believable.
Anyway, I've generated 7999 kWh electric this year 
Everything has come down in price, would certainly be a lot cheaper now, I also wouldn't build my own batteries, would probably use the Gobal Power batteries.
@Megahackerd As with everything, it depends what you want, how much flexibility, what quality, how much you're willing to pay etc. My inverter can easily exceed 8kW (they do a 12kW one as well) , it was pretty straight forward to connect it up so it could power the entire house in the event of a power cut -and my Solaredge system will keep running then as well.
I wrote my own code which runs on the Victron system to control forced discharging, how many inverters can you do that on?
@Megahackerd As with everything, it depends what you want, how much flexibility, what quality, how much you're willing to pay etc. My inverter can easily exceed 8kW (they do a 12kW one as well) , it was pretty straight forward to connect it up so it could power the entire house in the event of a power cut -and my Solaredge system will keep running then as well.
I wrote my own code which runs on the Victron system to control forced discharging, how many inverters can you do that on?
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@Troop, thanks for the heads up, they've certainly dropped in price, but I've no plans to build any further batteries, I wouldn't really gain much if anything.
I now have my heating system fully connected up, and the Cerbo will turn it on if/when the batteries get down to 8°C and turn it off at 12°C.
I've also now have my functional incubators, made from polycarbonate. I've basically got four sides, which bolt to the aluminium end plates, and a top, so each battery is enclosed. I've bolted three sides on both batteries, still need to make the mounts for the fourth side on each.
This is the only picture I have at the moment, its one of the end plates.
They certainly appear to retain the heat for longer, if its still not enough I'll have to wrap them in a fire blanket.
The last 24 hours temperatures. The orange and green line is the two batteries, the white line is a temperature sensor thats on an isolator that gets a bit warm - you can see how quick that drops off compared to the batteries.
I've also now have my functional incubators, made from polycarbonate. I've basically got four sides, which bolt to the aluminium end plates, and a top, so each battery is enclosed. I've bolted three sides on both batteries, still need to make the mounts for the fourth side on each.
This is the only picture I have at the moment, its one of the end plates.
They certainly appear to retain the heat for longer, if its still not enough I'll have to wrap them in a fire blanket.
The last 24 hours temperatures. The orange and green line is the two batteries, the white line is a temperature sensor thats on an isolator that gets a bit warm - you can see how quick that drops off compared to the batteries.
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Yes, been setup since April, BUT my Octopus usage doesn't show anything after 23:30 on Friday for electric, import and export. Funny how the Bright app shows the import though, clearly an Octopus issue.
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