Thanks for sharing. For long-term accurate readings of total consumption, I would probably use the registers from the "Total energy accumulator" section instead. Active Power becomes less accurate with lower poll frequency because it does not know when, if, or how consumption changed between readings. Also, there is a cheaper option: you can connect a pulse consumption meter to a digital input. It can be two or three times cheaper, and you don't need a Modbus extension. The downside is that you need a digital input for each meter, and you can only read consumption.
Thanks for sharing. For long-term accurate readings of total consumption, I would probably use the registers from the "Total energy accumulator" section instead. Active Power becomes less accurate with lower poll frequency because it does not know when, if, or how consumption changed between readings.
Also, there is a cheaper option: you can connect a pulse consumption meter to a digital input. It can be two or three times cheaper, and you don't need a Modbus extension. The downside is that you need a digital input for each meter, and you can only read consumption.
100% agree, do you have any specific Pulse meters in mind? The OB115 also supports pulse metering on the S0, but definitely not the cheapest..
can you use Modbus rs light switch? as they are way cheaper?
Yes, but it does depend on the switch and how configurable the protocol is