Hi, trying to understand easiest way to have a grid meter to the inverter on a long run (50m) single phase.
Was considering the following however I'm out of space in my consumer unit so will be costly.
ET112 - RS485 client - LAN - RS485 Server -> Victron Rs485 to USB cable Multiplus 2 GX (ESS)
Shelly EM gets a few mentions. Does anyone have any experience, is the 1 second delay problematic in a ESS setup?
Shelly EM gets a few mentions. Does anyone have any experience, is the 1 second delay problematic in a ESS setup?
It depends. I'm running a Fronius-Smartmeter, connected to my Fronius Inverter and a script to query it via http and inject the values on dbus. Round-Trip delay is about 500ms, so, with a target grid-set-point of 0 Watt, i'm seeing about 0.3 kWh pulled from Grid every day.
Price for another, direct-attached Grid-Meter would allow me to buy that 300 Wh for years and there is no guarantee that this would even resolve the "little-grid-pull" situation.
Only drawback is connectivity issues. Forgot to turn the Fronius inverter on after some maintenance, therefore the JSON-API was inaccessible and dbus values where stuck to "200 watt feed in", which caused the Multiplus to crank up their charge "per second" to try to zero out that feed in. (Fully charged the battery from grid, that day :P )
So, if you already have something like the shelly em, try it out, see if you are satisfied. If you don't have a grid meter now, buy "the right thing" so you don't have to worry about connectivity-issues and backup-measures.
