Our system has failed, I heard the inverter alarms going off and noticed that the Utlility feed to the inverters had tripped. I reset it, the inverters show AC Input but the watchpower program shows no AC Input voltage. I have changed the settings to Utility Output Source priority, Utility Charge Source Priority, from the SMH Program I cancelled the SOC option and chose UTI/SUB as the mode. But it will not start working again. When I reset the batteries (6 x 3.5kW Pylontech) it does not go into bypass mode. Any ideas please?

The AC Voltage displayed on the Inverters is 275V is this too high? Should be 230V

 

1 hour ago, Paul Vermeulen said:

The AC Voltage displayed on the Inverters is 275V is this too high?

Probably. You didn't say what model, or even what brand, but for instance the Axpert King lists the high loss voltage as 280 V ± 7 V, so it could be as low as 273 V.

You should find out whether the utility voltage really is that high, by measuring carefully and safely with a multimeter. But if it really is that high, all sorts of appliances would be popping.

So most likely, your inverter is reoirting the mains voltage too high. There are a handful of resistors that are likely to have failed if this is the case. So if you are handy with electronics, this is likely an easy and inexpensive fix. Otherwise, you'll need it repaired, and they are likely to replace the whole main board at about half the cost of a new inverter.

54 minutes ago, Coulomb said:

Probably. You didn't say what model, or even what brand, but for instance the Axpert King lists the high loss voltage as 280 V ± 7 V, so it could be as low as 273 V.

You should find out whether the utility voltage really is that high, by measuring carefully and safely with a multimeter. But if it really is that high, all sorts of appliances would be popping.

So most likely, your inverter is reoirting the mains voltage too high. There are a handful of resistors that are likely to have failed if this is the case. So if you are handy with electronics, this is likely an easy and inexpensive fix. Otherwise, you'll need it repaired, and they are likely to replace the whole main board at about half the cost of a new inverter.

Thank you for the reply.

Our transformer was recently replaced after a tree fell on the power line and snapped the mounting pole and damaged the original transformer. The voltage is high, I have checked it with a multi-meter, but the system was working. I recently bought 2 new Axpert inverters SOL-I-AX-5P64 to get the higher Solar Input current of 80A to match our Solar Panel array. At the moment the inverters are charging the batteries from Solar, but are still reporting that there is a Utility failure.

Most of our appliances run through the inverters, where the output voltage is shown at 230V 50Hz, though in bypass mode I always assumed that the load was fed directly from Eskom through the inverters. We have not had a problem with anything burning out yet.

As soon as there is enough solar power I will try and turn the system on gain to see if it starts working, and then try to find out what tripped the utility power supply to the inverters.

8 minutes ago, Paul Vermeulen said:

in bypass mode I always assumed that the load was fed directly from Eskom through the inverters.

Yes. But with that high utility voltage, they won't switch to line or bypass modes. In line mode, the inverter output would be in parallel with the utility, so that will also result in 275 V at the loads. The switch from 230 V to 275 V would be brutal on the relay contacts.

I think you have to get someone to adjust the taps (if any) on your transformer. Does that transformer supply just your residence, or a whole block of houses? In Australia, it's a whole block.

Most appliances would tolerate 265 V absolute max. There should be no argument that 275 V is acceptable.

OK Everything is working again now, just need to find out why it happened!

If you mean that it's now "working" with utility voltage still at 275 V, it's possibly because of the high hysteresis of the AC-in voltage cutoff. Considered too high at 280±7 VAC, and considered OK again at 270 ±7 VAC. 275 V is right in the middle, so you might have just had a slight surge to trigger it, then it won't go off until you reset, or the utility voltage dips enough to trigger resetting of the "too high AC-in" flag.

My guess is that another slight surge will trigger it again soon. Your utility voltage is right on the very edge of being too high for your inverter, and if you go to line or bypass modes, it will likely fry other equipment. In the meantime, your relays in your new inverters will be getting a hammering, not to mention the switching transistors.

You need to report the grid high voltage to your utility, 275V is far too high.

Yes I will report the high voltage to our power provider, when the supply voltage dropped to about 265V AC the units recognised the Utility Input and started working again. And I found the reason that the utility feed to the inverters tripped, during the recent floods I bought an industrial Wet/Dry vacuum cleaner to help get rid of water, I have just found that it is 3500W and my wife was using it on the solar circuit. That combined with the usual load tripped the circuit breaker in bypass mode. Of course we only found out after the batteries went flat.

 

Just to follow up I borrowed a Thicknesser Planer to repair our flood damaged wooden floor, the overload kept tripping. So I replaced the overload with an On-Off switch, and burnt the motor out. After I had it rewound I checked the current draw on Eskom power, it was close to 270V AC 14A (rated 6.5A Full Load). I then tested it on my inverter circuit and it was drawing exactly 6.5A. So I called Eskom, the technician admitted there was a fault, he managed to connect our power supply to different connectors on the transformer, and got the voltage down to about 240, which he says is the new norm and acceptable. But now I know why my electricity bill is so high!. Thanks for the advice.