Hi, hope it's OK writing about more than one thing in a topic.
Our PV array is 6of 550w panels - 3.3kW total, wired in 2 strings - 120V. North midlands UK. Mounted at less than the ideal angle (you deal with what you have) - approx 18deg. So I'd expect maybe a max of 2.2kW at peak conditions (approx 65% max output).
Pytes Ex box 48100R batteries (no they're not rebadged Pylontechs although I believe they use the same cells, the build, BMS, comms etc are all different) (2of 5.12kWh) and Conversol V7 inverter 5kW.
Today it's sunny.
The inverter says we're charging with 32A from PV only. There's a fair delay between what you see on the front panel and what you see on Watchpower but after a while, Watchpower correlates. However it says PV power (from the panels) is only 2.1kW. If the power is only 2.1kW how can we be charging at 32A when there's no current being fed in from Utility (SBU mode)?
It's quite difficult to see what's actually going on generally because of the delay but it never adds up. I'd generally expect what's reported as charging power to be less than what is possible from the array (being reported) at any time because the house is also running from the same load, it's not all going to the batteries?
On another topic completely. Last week the batteries were drawn down a lot due to all the cloudy weather we've been having and we kept getting an error 04 - low battery voltage. The lowest battery SOC is controlled wholly by the BMS, there's no control over that. I've done plenty of searching on this topic and error 04 comes up over and over. I assume that at the time of day (early morning) the batteries where sufficiently discharged (we were running in SBU mode and the batteries were showing 1 LED charge left) that minimal draw on the battery caused them to drop below the minimum voltage set in the inverter which was at the time the default (I think) 46V. Now I'm assuming what happens is that once the warning is triggered ,it stays in the warning state until the 'back to battery voltage' that has been set in the inverter has been reached or (I believe) 4V above the low voltage limit. I found that as solar for a few days was so low all I could do to get out of the warning state was to manually change mode to bypass, then USB (and left it) until the battery was quite well charged again.
Since then I've upped the lower battery voltage limit to 50V and the back to battery to 54V (actually I think 54V is the default anyway) but this doesn't seem to stop the batteries drawing right down the same, all it seems to do is ,is if you hit 50V due to inrush from an induction hob or washing machine (say) strobe the inverter into bypass until the situation is over when there's good charge in the batteries- which is what it should do, BUT, when the batteries are in a low state of charge you still get error 4, and in that situation it isn't putting the system in bypass? Why would that be?
Hope I've explained it well enough.
Other settings:
1 Output source priority: SBU (solar battery utility)
2 Max charge current: Set automatically by the BMS - 100A
05 Battery type: LIB protocol
10 Operation logic: Aut ( if selected & utility is avaiable inverter weorks in line mode. Once util freq is unstable inverter works in bypass)
11: Max charge current 30A
12 set voltage point back to utility source when in SBU: 50V
13 set voltage back to battery when in SBU: 54V
16 solar priority : SLB UCB (solar for battery first, allow utility to charge)
23: bye (bypass enabled)
26 bulk charge voltage: set by bms to 56.8
29 float charge voltage: set by bms to 56.8
20 low batt cutoff voltage: set by bms to 45.5
Just checked Watchpoweragain, it reckons 26A charging but only 1751W at the panel, 178w to house (errr....1751-178 = 1573/120 = 13A.....??????)
Our PV array is 6of 550w panels - 3.3kW total, wired in 2 strings - 120V. North midlands UK. Mounted at less than the ideal angle (you deal with what you have) - approx 18deg. So I'd expect maybe a max of 2.2kW at peak conditions (approx 65% max output).
Pytes Ex box 48100R batteries (no they're not rebadged Pylontechs although I believe they use the same cells, the build, BMS, comms etc are all different) (2of 5.12kWh) and Conversol V7 inverter 5kW.
Today it's sunny.
The inverter says we're charging with 32A from PV only. There's a fair delay between what you see on the front panel and what you see on Watchpower but after a while, Watchpower correlates. However it says PV power (from the panels) is only 2.1kW. If the power is only 2.1kW how can we be charging at 32A when there's no current being fed in from Utility (SBU mode)?
It's quite difficult to see what's actually going on generally because of the delay but it never adds up. I'd generally expect what's reported as charging power to be less than what is possible from the array (being reported) at any time because the house is also running from the same load, it's not all going to the batteries?
On another topic completely. Last week the batteries were drawn down a lot due to all the cloudy weather we've been having and we kept getting an error 04 - low battery voltage. The lowest battery SOC is controlled wholly by the BMS, there's no control over that. I've done plenty of searching on this topic and error 04 comes up over and over. I assume that at the time of day (early morning) the batteries where sufficiently discharged (we were running in SBU mode and the batteries were showing 1 LED charge left) that minimal draw on the battery caused them to drop below the minimum voltage set in the inverter which was at the time the default (I think) 46V. Now I'm assuming what happens is that once the warning is triggered ,it stays in the warning state until the 'back to battery voltage' that has been set in the inverter has been reached or (I believe) 4V above the low voltage limit. I found that as solar for a few days was so low all I could do to get out of the warning state was to manually change mode to bypass, then USB (and left it) until the battery was quite well charged again.
Since then I've upped the lower battery voltage limit to 50V and the back to battery to 54V (actually I think 54V is the default anyway) but this doesn't seem to stop the batteries drawing right down the same, all it seems to do is ,is if you hit 50V due to inrush from an induction hob or washing machine (say) strobe the inverter into bypass until the situation is over when there's good charge in the batteries- which is what it should do, BUT, when the batteries are in a low state of charge you still get error 4, and in that situation it isn't putting the system in bypass? Why would that be?
Hope I've explained it well enough.
Other settings:
1 Output source priority: SBU (solar battery utility)
2 Max charge current: Set automatically by the BMS - 100A
05 Battery type: LIB protocol
10 Operation logic: Aut ( if selected & utility is avaiable inverter weorks in line mode. Once util freq is unstable inverter works in bypass)
11: Max charge current 30A
12 set voltage point back to utility source when in SBU: 50V
13 set voltage back to battery when in SBU: 54V
16 solar priority : SLB UCB (solar for battery first, allow utility to charge)
23: bye (bypass enabled)
26 bulk charge voltage: set by bms to 56.8
29 float charge voltage: set by bms to 56.8
20 low batt cutoff voltage: set by bms to 45.5
Just checked Watchpoweragain, it reckons 26A charging but only 1751W at the panel, 178w to house (errr....1751-178 = 1573/120 = 13A.....??????)
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