question

Hi @Pekie

I very much doubt that there's anything wrong with your Quattro. It's likely related (broadly) to the rejection of the generator power.

I see this myself with a Multi 48/5000, but usually only when I have little 'base' load when bringing on a hefty demand. With say a 2000W load running before switching in more, it doesn't happen. Generator issue?, just a maybe, but still possible. A dicky ac connection from the genset can do it. Might work fine normally, but a high resistance joint seems to get picked up by the Victron as 'distortion' or something. Maybe the earthing can contribute too.. dunno?

I have Dynamic Current Limiter checked to give the gen a chance to wind up. Then Power Assist will come into play too, and it has a Boost Factor setting. Info on that is awfully sketchy, and I'd love to see this described more comprehensively, the pros/cons of high/low settings. I haven't got around to testing that myself, but you could try..

Sorry I don't have that silver bullet for you, but maybe you can pick something out of this. Clues from other users I'd surely welcome too..

hello peckie, Your watermaker may have a high inrush current which may cause the generator to momentarily sag in voltage until it can recover from the shock load. If that happens the AC 2 output of the Quattro will disconnect. I am no expert but have a suggestion for you. Like the previous answer I would engage dynamic current limit so an abrupt change in load will be handled by the inverter boost until a few second has passed.

Also, I would reduce the current limit below the capacity of the generator and ensure power assist is active to see if that helps. The reason for this is to stop a shock load on the generator at well below its rated capacity. A generator has a rated capacity but if you dump a load on a generator at its rated capacity it will fail. The load should be staged in to allow the generator to build up to its rated capacity. By setting the input current limit lower than the generator capacity you reduce the possibility of the generator being overwhelmed even for milliseconds by the shock load. That would be worth experimenting with.

I doubt the Quattro has a problem and think the setting of those parameters may help get that watermaker working again.

@JohnC , @Trevor Bird ,

Thank you for the tips. I played around with the dynamic current limit and power assist function and it works wonderfully with all of my equipment but unfortunately not with the watermaker. I am thinking that the inrush current is just too high for the generator and makes the Quattro disconnect. However it worked on my old Quattro in this setup. So I am thinking that maybe the starting capacitor of the watermaker pump is defective. I ordered a new one to try and will post my findings soon

Hello, did you try reducing the current limit on the input the generator is supplying? What I mean is if the generator is 5000watt, it can provide at full load about 20 amps at 240 volt . Reduce the current limit on the Quattro input to let’s say for an experiment, 12 amps and see if it still happens. That way, when the inrush on the watermaker reaches 12 amps, the Quattro inverter will power assist using battery power to overcome the inrush. You can be pretty sure the generator will not be overwhelmed by that current limit and see if it works. If it does work, creep the current limit up to as close to the generator capacity as you can until it fails. You then know what the point is the generator cannot handle the inrush and you can set the current limit just below that point.

I hope this helps.

@Trevor Bird

Yes, I did try that but it doesn't make any difference for the watermaker, but I can notice that if I, for instance, turn on the air conditioning the inverter kicks in when I have a low current limit set. The watermaker high pressure pump immediately disengages the Quattro transfer when it's switched on and powered by the generator. But on shore power it works flawlessly and the Quattro handles it beautifully. You can see the LEDs of the inverter flash for a moment to power assist. I have both the shore power and generator power limited to 16amp because my shore power Victron isolation transformer is only 3500 watts @ 220v

If I connect the watermaker directly to the generator it will work but I can hear the generator engine struggle for a second before the pump starts. So I think you are right about the high inrush current. Maybe the inrush is so high, the Quattro just cannot handle it. But it worked on the old Quattro, that's why I am thinking that the capacitors are bad.

@Pekie

Amazing the generator cannot handle the inrush even when power assisted. Ok, the Quattro will disconnect when the input voltage is too low or too high. Check the low voltage setting. I think it defaults to 187volts from memory but if it is set too high when the generator voltage sags a little it will disconnect.

@Trevor Bird

I tried a few different values with that setting. The lowest was 170v if I remember correctly but with no results. If I connect the water maker directly to the generator I hear the engine struggle for a moment when the watermaker starts then it just runs fine but when the Quattro is in the setup I don't hear a change in the generator engine RPM. The Quattro switches to inverter power assist for a second and then disconnects the load.

If I really load up the Quattro while powered with the generator the power assist works fantastic. I can run 2 x 16k BTU air conditioning, microwave, electric stove at the same time. Easily more than 5k watts.

@Pekie just wondering if you have disabled UPS? My understanding is that the Quattro is more selective of the sine wave shape at the input if UPS is a selected. If it is not selected you will see a very short break on AC output 1 if shore power or generator is lost. That may be worth a try.

good luck.

@Trevor Bird

Yes I tried with UPS enabled and disabled. A while back I found this document from Victron that gives a couple of specific settings for a generator. Basically if the generator does not connect the advice is the disable UPS and check weak AC. I tried all the settings mentioned in that document without success. I also read somewhere that my problem could be caused by a ground fault. I noticed that my watermaker chassis is not grounded as stated in the manual. I wonder if that could be it or there is this ground relay setting in VeConfig software that I could try. Anyways if I can find a good electrician around here I will have checked how much the inrush current actually is and if that is the problem or not.