Does a modbus register exist with a higher resolution value of the calculated SOC ?
Actually this value increments by 0.5
what do you need that for? it can´t be that accurate
To increase the ESS grid setpoint automatically with node-red when the SOC gets close to the minimum SOC.
i still dont see the benefit – dou you want to save more money with that solution?
Even if SOC reports 16% it could also be 10 or 22
It would not only be pointless for a measuring instrument to display values significantly more precise than its actual measurement accuracy allows, but even misleading. For instance, it would give the user the false impression that the SOC is still at 15.3%, when in reality it is only around 5%.
I’m using register 266, which reports in 0.1% steps. dbus at com.victronenergy.system/Dc/Battery/Soc has even more digits, but I think those are basically noise.
But the resolution might depend on what your SOC source is – my JKBMSes lie to me in increments of 1%.
thank you for the reply. I will give it a try.
No luck for me. Register 266 does not show a higher resolution and path com.victronenergy.system/Dc/Battery/Soc neither.
i’m aware of the absolute drift between the real SOC and the calculated SOC. It is the change of the SOC that is of interest to me. Mathematically it is dSOC/dt
Since you are looking for a discharge rate, which change of SOC over time is, you could use the battery current and capacity instead. Since the rate of change of SOC (dSOC/dt) is just I/C. Or not? Discharging a 400Ah battery at 4A would give you a 0.01 rate
I decided to make my own SOC high resolution calculation with Node-Red. Thanks for the tip chrigu