Hi all, im having fliclering problems with my inverters. All works fine if only one is powered on, if i power on second inverter and sun power is awailable l, voltages on invertes start to vary abot 5 volts, power delivered by them is inconsistent one is delivering 1200 sencond 800 an it is changing, a can see it on led lights how inverters fight. It get worst when power is greater it flicker almost i would say no power for 0.1sec. but if there is dark outside and it works obly with batteries all is good, no voltage and power differences between them. I have tried to put ferite cores on all possible cables to get rid of noise but it didnt helped, aso tried to restart them and change main and slave, nothing helped, they woked fine while on they own too. Just paralel while sun is problem. Could some provide some help please?

27 minutes ago, janco93 said:

Hi all, im having fliclering problems with my inverters. All works fine if only one is powered on, if i power on second inverter and sun power is awailable l, voltages on invertes start to vary abot 5 volts, power delivered by them is inconsistent one is delivering 1200 sencond 800 an it is changing, a can see it on led lights how inverters fight. It get worst when power is greater it flicker almost i would say no power for 0.1sec. but if there is dark outside and it works obly with batteries all is good, no voltage and power differences between them. I have tried to put ferite cores on all possible cables to get rid of noise but it didnt helped, aso tried to restart them and change main and slave, nothing helped, they woked fine while on they own too. Just paralel while sun is problem. Could some provide some help please?

What make and model inverters? 

Do they run on the same firmware? 

Is each inverter connected to their own panels and are panels in the same direction and strings the same? 

Inverters are same firmware, strings are different one is about half smaller and on flat roof same direction. 

Edited April 21, 20242 yr by janco93

I have also notice that input grid reading is getting off too during this parallel operation, but as well only when sun awailable. With only one of them active all good.

2 hours ago, janco93 said:

Hi all, im having fliclering problems with my inverters. All works fine if only one is powered on, if i power on second inverter and sun power is awailable l, voltages on invertes start to vary abot 5 volts, power delivered by them is inconsistent one is delivering 1200 sencond 800 an it is changing, a can see it on led lights how inverters fight. It get worst when power is greater it flicker almost i would say no power for 0.1sec. but if there is dark outside and it works obly with batteries all is good, no voltage and power differences between them. I have tried to put ferite cores on all possible cables to get rid of noise but it didnt helped, aso tried to restart them and change main and slave, nothing helped, they woked fine while on they own too. Just paralel while sun is problem. Could some provide some help please?

Is the inverters Easun ISolar SM II 5K plus-48?

You need to confirm if the 2 inverters are properly synchronized. Disconnect loads and measure the L on both inverters output with a multimeter there should be <5vac diffrence between the inverters. Leave them on for a while and ensure that the L voltage diffrence does not change. 

I think that it should not be a problem because if there is no solar power available everything work great, no voltage fluctuations no flicker.

1 hour ago, janco93 said:

I have also notice that input grid reading is getting off too during this parallel operation, but as well only when sun awailable. With only one of them active all good.

This is very weird that you also find that the grid voltage is fluctuating when there is solar available to the inverters. The inverters cannot change that but 1 could be just reading a wrong voltage but strange that all is fine if no solar input when they work stand alone. 

Edited April 21, 20242 yr by Scorp007

Here is same voltage, one is off

When it is reading different in output it aslo reading differen input, that is super weird. I have also tried to move signal cables more away from solar cables to avoid noise but it did not help at all.

Could the wiring, either external or internal to inverter 1, be high resistance? It like as soon as inverter 1 consumes power, the measured voltage goes down way too much. It could be wiring, breaker, wire loose in terminal block, etc.

You could also check  the voltage at the AC-in terminals of inverter 1 with a multimeter.

What happens if you switch inverter 2 off with inverter 1 on?

Edited April 21, 20242 yr by Coulomb

Ok so status update, if i turn both on with solar available it flickers, if i disconnect solar from one of them is stops flicker.... Sun is going down so i cant 100 confirm but it seems like it is doing only if there are both inverters connected to solar. I have one more spare charger so i will try to disconnect one inverter from solar and put it to charger, i will let you know the results.

Ok so i can confirm, if i disconnect one of inverter solar input and connect to separate charger everything work great. So solved problem for now but itnis not ideal solution for me, anny suggestions to how connect it back and not flicker? 😀

I have the same problem with easun SV IV 5.6 kW inverters. Did you manage to find a solution?
Thank you for your response.

On 2024/04/27 at 9:44 PM, Jaro said:

I have the same problem with easun SV IV 5.6 kW inverters. Did you manage to find a solution?
Thank you for your response.

Try disconnect panels from your inverters and leave only one, it solves my problem, but you need to connect rest of panel somehow differently 

Paralleled inverters must have separate PV strings, but I assume you both know that. The strings don't have to be similar at all, just electrically separate.