1) Check Nominal Voltage settings for DG and BUS, must be similar in all the sets.
2) Check default droop settings on the AVR. Set AVR droop similar for all the Gensets.
3) Check individual DG on load, note down kVAr on each phase and total PF value. Use the same amount of load to test other DG’s in the system.
4) Make sure that all DG’s show same PF value and KVAr values are also closely matching. In case for any of the DG, read PF value is lower than actual expected/than seen on other DG’s; cross verify the Phase sensing and CT sensing order. Means check that L1 phase CT is connected in L1 CT sensing terminal, L2 phase CT in L2 and L3 phase CT in L3 phase CT sensing.