Hi,
I’m having wrong calculations on my ET112 grid meter, that I’m not finding the reason…
I’m using the ESS assistant and I’ve the grid set point to 0 (also tried with -10w), but the system seems to struggle to keep it near to 0w with no injection:
and even when I’m injecting, the calcs don’t look right:
This is causing me unnecessary consumption from the grid (2 or 3 kw per day)…
Any idea why this is happening?
In short: sensing/rounding errors, reaction delay and hysteresis.
Near 0W it gets tricky to detect the current flow and react fast enough to changes in power usage.
You’ll always “wiggle” around the setpoint.
If you want true 0W grid usage, best option is to connect all consumers to AC Out and disconnect the grid.
My biggest concern is not the 0w, but the fact that some times the real consumption can be > 0.5kw (even showing very low number of watts in the grid meter, what causes costs…
For example, this is from my grid provider… where we can see that between 31/4 and 06/5 we have overnight consumption and after 07/5 it is normal (just little adjustments to try to keep it near 0w):
In none of these days, I had the need to consume from grid, as my batteries were always almost full…
it’ very strange, because in the meter you see the amps being consumed (~2amp at 230v, what means ~460w), but the same grid keeps saying something around ~20w…
This is not only the speed in catch up to remain near to the grid set point, but for me it seems the meter is guiding wrongly the Multiplus II, that ends up pulling from the grid believing its near to 0w… or maybe I’m seeing this wrongly…
