Adding a 2nd Hybrid inverter...

Looking at adding a 2nd hybrid inverter to go with my expanding solar arrays. Question; will the second inverter need its own grid monitoring CT or will it 'talk to the already commissioned inverter ?
here is my current set up.
GivEnergy Hybrid 5.2 inverter on the back of the office with the EPS output feeding the office
4.3 kW of solar PV on the main roof using solar skirt as bird protection. Feeding into MPPT 1
2.5 kW of solar PV on the office. Feeding into MPPT 2
8.2 battery will be added in June.
Zappi charger
Eddi

rob1980 we’ve got two HY5s which are completely separate except that they both connect via their MCB to the consumer unit. They have their own battery, PV and EM115 tracking grid import/export. They do work well together load sharing and they discharge their batteries overnight to 1-2% of each other, so well balanced. Not sure how load balancing would work for you as I don’t believe you can connect the two EPS circuits.

Tim thanks Tim.
All sounds good, my only reservation; my EM115 is located 50 meters away in the supply meter cupboard and hardwired using 2 core RS cable back to my HY5 (50 meters away). All cables are trenched and not easily accessible. Kicking myself I didn't run more cables...

I could try LoRa's again, but I did not have much luck with them last time 😅

rob1980 Our installer used Cat 5 cable between the EM115s and the inverters so even if I had faulty cores or a need for additional meters, there's still spare capacity.

rob1980
I have been looking at adding a second 5kw hybrid inverter and Givenergy have just sent me this response...

"We do not recommend the dual hybrid system as we do not yet have the logic or product (EMS) available for the plant system, although it will work generally it will not work seamlessly and will have bugs."

I emailed Givenergy as my installer said this...

"unfortunately we have been told by GivEnergy, we cannot add a second AC Charger or Hybrid inverter at this stage. They are working on a fix to this but have nothing to allow for this currently. Give there Technical team a ring on 01377-252874 if you can please mate and they will explain this to you."

I currently have 5.9kw with 2 strings into a single 5kw Hy and 2x8.2kw batteries.

derekfairweather i think @Tim runs 2 hybrids together with relative success from a technical standpoint (in that he has power from them)
Think the monitoring side of things are a bit wonky though so the app and portal may not be telling the whole truth.

I suspect what youve been told stems from an ongoing issue with plant setups that have issues working together reliably and rather than sell you another and receieve yet more bad feedback its probably better from a brand stabdpoint to hold off selling you one until the fixes are well and truly nailed down.

hoggy
Thanks for clearing that up, I will wait till the issues are sorted. Soon hopefully

derekfairweather although it will work generally it will not work seamlessly and will have bugs

As @hoggy said, our installer put in two HY5s each with its own PV, battery and EM115. They are completely separate except they both connect to the same 240Vac "Solar" consumer unit which connects through the MCS meter to the house consumer unit. I was concerned about whether the two hybrids would continuously "fight" each other, ramping up and down but they don't. They just work and work really well. I suspect that they have identical configurations and consequently, start to ramp output up and down at exactly the same value. When the 3kW kettle or oven is switched on, the grid import blips for maybe 10-15 seconds while the two inverters ramp up to match demand. Similarly, when the kettle boils and switches off, export is 3kW reducing for about 10-15 seconds while the inverters ramp down.

My only complaint is that the portal data is awry but the actual plant works really well. On the other hand, I might just be really lucky to have two inverters that are so well matched. If the voltage detection circuit (or setting) on one was 1V different from the other, maybe they wouldn't play so well together and one would be doing all the work.

Tim Hi Tim,
Sorry to bother you - I'm having a dual hybrid system fitted soon, I was wondering if you would be able to share some photos/schematics to ensure I don't have any problems with the installers.
I noted that you've not had any problems but others have some issues with this set up.
Thanks in advance

94jdh Hi, This is a photograph of the business end of the installation for one of our hybrids. I took the photo to make a poster to go next to the inverters showing the shutdown and startup procedure.

1. AC isolator
2. battery on/off button
3. Battery isolator
4. PV Isolator (enables the inverter to be disconnected from PV)
5. Built-in PV isolator

The mains side of the ac isolator for each inverter goes to its own 32A MCB in the "Solar" consumer unit. The isolator of the "solar" consumer unit is cabled through the MCS meter to a 63A MCB in the main house consumer unit.

Hope this helps

Tim that's a great help thanks- want to make sure I don't have problems when mine is installed.
So you only have the one meter, and don't have of these issues with one inverter fighting the other by discharging and charging each other?

94jdh fighting the other by discharging and charging each other

No, but ... On the plus side, I updated the firmware on the two batteries from 3001 to 3005 earlier this week and again 3005 to 3007 yesterday and today. I was able to discharge the battery to the EV and charge from solar and the other battery/inverter. Total grid import during battery recalibration that has been done three times this week (one failed on the first firmware update) has been just over 1kWh above the normal 5-600Wh/day. It would have been practically zero except that the discharge started late in the day and we've had quite a lot of passing cloud.

Both batteries are now 100% SoC and firmware 3007 although export has been lower than normal during the period.