Hi Guys

I have just had a system installed yesterday and my installers are lost for words with what my inverter is doing. They have tried 3 X different inverters and they all do the same thing when the AC is connected. They have done all the neccessary checks on the wiring of the AC and everything is correct (checked by a qualified electrician) When the inverter is on solar only it is happy and behaves normally but the moment you attach the AC to the system the screen starts jumping all over the place icons flashing on and off arrows appearing and dissapearing). At night when the panels shut down it shows the AC but no arrow to the batteries. The installer has triple checked the settings according to the Mercer manual and everything their is as per spec. It is a 48v 5KVA inverter with 2X 48v lithium ion batteries each holding 5.5KVA. They will be returning on Monday afternoon to have another attempt at sorting it out but I was just wondering if you guys have experienced this before and had an explanation for it. 

3 hours ago, Marc Swindells said:

When the inverter is on solar only it is happy and behaves normally but the moment you attach the AC to the system the screen starts jumping all over the place icons flashing on and off

That sounds vaguely like a known problem with Axpert MKS IVs, except with them, it's PV that triggers flashing icons. Those are models with the round colour display. This one sounds like a removable display. It could be that the utility power supply is faulty and injecting noise into the system, and it happens that the display suffers in such a way that it's very visible. Other things may be going screwy internally, and you'd not know until you get past the display issue.

3 hours ago, Marc Swindells said:

They have tried 3 X different inverters

If they are all the same model, then perhaps this is a bad batch? If so, it sounds like it could be expensive for all concerned.

Sounds exactly like the PV issue which is easily fixed, very surprised it's happening with AC grid input

3 hours ago, Marc Swindells said:

Hi Guys

I have just had a system installed yesterday and my installers are lost for words with what my inverter is doing. They have tried 3 X different inverters and they all do the same thing when the AC is connected. They have done all the neccessary checks on the wiring of the AC and everything is correct (checked by a qualified electrician) When the inverter is on solar only it is happy and behaves normally but the moment you attach the AC to the system the screen starts jumping all over the place icons flashing on and off arrows appearing and dissapearing). At night when the panels shut down it shows the AC but no arrow to the batteries. The installer has triple checked the settings according to the Mercer manual and everything their is as per spec. It is a 48v 5KVA inverter with 2X 48v lithium ion batteries each holding 5.5KVA. They will be returning on Monday afternoon to have another attempt at sorting it out but I was just wondering if you guys have experienced this before and had an explanation for it. 

Hi  @Marc SwindellsI assume that your system is actually performing, except for the noisy display. 

If it is the Axpert MKS IV it is a known problem when pv is active and under load.  The emi generatef by MPPT is causing interference to the display which is only about 2cm from the MPPT. 

SegenSolar has a modkit that they introduce for their Kodak range. 

Incidently I repaired an MKSIV this morning and had the problem under pv load. I pulled the display away from the mppt and the noise disappeared. 

Contact 

@Steve87 for additional info.