Is an additional counter necessary if I want to control the active power limitation via a Sunny Home Manager?
If you want to use the Sunny Home Manager correctly (e.g. to systematically operate devices automatically from less expensive current or to show your own consumption and find power guzzlers), the Home Manager must also know the consumption. A grid feed-in and consumption counter are required for this (two separate counters in one housing—connected via a D0, S0 interface, or even “mixed”—one D0, one S0 counter).
Ensure that the counters are sufficiently precise. With S0 counters, this means at least 500 pulses/kWh; with D0 counters, the precision must be at least 1 Wh. If the counters do not have this level of precision, they cannot be used for active power limitation.