Is it possible to use meters and a CT sensor connected to the same inverter? I currently have 2x EM115 connected to grid import/export and a FIT solar installation. I'm adding another solar installation - can I use a CT sensor to monitor this in addition to the existing meters, or will I have to install another EM115 and add this? I believe the installation will have to be re-commissioned to add either of these options? Thanks!
even my installer installed these EM115 meters which are totally useless as Octopus Energy does not use it. i have no idea why it was installed in the first place.
OE uses the reading from the main meter they had installed, its capable of both import and export readings.
In my ongoing debates with Octo and my "dumb" smart meters, Octo will not accept any data from the EM115 or downloaded from the GivEnergy portal (including the script that rtidey wrote) as proof of how the system is configured and working.
I was on Flux and my meter recorded total import and export but not half hourly times. The rtidey extract shows all the half hour data adding up to the same totals as the meter, but their answer was "can't use 3rd party data".
No explanation, even though Octo and GivEnergy supposedly partner.
https://community.givenergy.cloud/d/2881-report-data-download-as-excel-file
SteveCook Well I use the EM115 meters principally as a way of getting information from the main board over cat5 to the inverters which are too far to use direct CT connection. So I’m really looking to share this info(grid import/export and existing solar generation) to the hybrid as week as the AC coupled inverter. Since the meters put the information on a bus based system(RS485/modbus) presumably any device on the bus can make use of this? In other words I shouldn’t need to duplicate these meters?
The meters are probably not certified for billing purposes.
anglefire EM115 is MID approved
CleoBattery I tried this and it just ends up a jumbled mess - the data comes through that the grid is 3000+V and its operating at 200+HZ which makes the inverter very upset.
There may be some trick with plant mode commisioning making sense of it (suspect this is a Master/Slave issue and each inverter tries to overule the other) but I ended up with 2x EM115 meters rather than messing about with that hot mess.
Wanted to not sacrifice yet another way in the board to fit the EM115 but wasn't to be.
Things may have changed since, this was back on Gen1 stuff.
You could share the cable if your inverters are next to each other? Still need multiple EM115 but use a twisted pair for each meter on the existing Cat5 cable to save pulling another?
SteveCook So it is. It will probably be the platform that won't comply then.
CleoBattery If the inverter (The gateway) supports multiple masters, then the modbus signals can be used by multiple devices - but not all do and only accept one. In this case, the primary inverter is the gateway reading the meters, and the second inverter would have to be able to connect to the primary over tcp to talk to the meters via modbus - which I doubt it can. It may be possible for it to work via the API - but I doubt that too.
You couldn't put both inverters on the same RS485 as you would then have two masters polling the meters - and the data coming back would not necessarily match what was asked and as Hoggy says, be a hot mess!
hoggy yes I could try that. I would need to install at least one more meter if I did it that way. But I had a reply from Givenergy support that this is possible, but they said “we don’t recommend using more than one inverter on a single phase”. I’m keen to use two inverters each with battery to increase the available discharge rate for using oven etc. I will see if it works when commissioning the second(hybrid) Givenergy inverter. The first one is an AC coupled system and has 2x EM115 meters giving grid and FIT solar monitoring.
CleoBattery further to this email and doing a brisk bit of Googling it looks like modbus over RS485 serial is one master(inverter) and several slaves(meters). Modbus TCP over Ethernet is capable of multiple’clients’ (inverters) and multiple ‘servers’(meters) but of course this is not how the inverters are configured. I think I will order a couple of extra meters and ct clamps and duplicate the setup via a seperate twisted pair in the cat5 for the second inverter to avoid problems.
CleoBattery I have two inverters and they both have their own ct clamps. Only 1 meter though for the combined solar battery installation
geoffreycoan can you give a bit more detail Geoffrey - presumably your ct clamps are monitoring the grid, what is your meter (em115?) monitoring, and is it connected to both inverters, just one, or is it doing something else?