Rusti Posted July 10, 2020 Share Posted July 10, 2020 Hi All, I have an Axpert 5kva, 6x330W panels and 1xUS3000 pylontec as a backup system. I had a generator switch over installed when the system was put in for when the utility is out for extended periods and overcast weather. I had to use this yesterday for the first time, and now have some questions about the Axpert settings and if i need to change anything when i run the generator. As far as i understand when i switch over to the generator the Apxert thinks this is utility and continues as normal. This worked fine and my battery charged to about 80% before the utility light started flashing and charger circuit light when off and the battery obviously stopped charging. I reset the battery and inverter a few times and disconnected the load (turned of plugs trip switches) to see if a struggling generator could be the problem, but this did not fix it. This made me think that i may need to change some setting when running the generator compared the the utility. I have included my settings below (not sure what model Axpert or where to find this). I would appreciate any input on this, i am very nervous running the generator in case i damage something, but in reality it is going to become more necessary in the future. Thanks 01=sub 02=30A 05=Pyl 10=Aut 11=30A 12=46 13=52 16=Sbl UCb 23=byE 26=53.2 27=53.2 29=47 Quote Link to comment Share on other sites More sharing options...
jykenmynie Posted July 10, 2020 Share Posted July 10, 2020 While I can't help you with your original issue, I do want to note to you that 1xUS3000 isn't powerful enough for a 5kVA inverter. It can only continuously provide 37A. This is worth about 1800W before DC to AC losses (so probably only 1600W on the AC side). If you draw more than that from the battery continuously, it would shut down eventually (at least, this is my understanding from other's experiences). Quote Link to comment Share on other sites More sharing options...
introverter Posted July 10, 2020 Share Posted July 10, 2020 52 minutes ago, Rusti said: As far as i understand when i switch over to the generator the Apxert thinks this is utility and continues as normal. This worked fine and my battery charged to about 80% before the utility light started flashing and charger circuit light when off and the battery obviously stopped charging. I reset the battery and inverter a few times and disconnected the load (turned of plugs trip switches) to see if a struggling generator could be the problem, but this did not fix it. I am not generator or axpert "certified", so double check with others but yes, the generator takes over the role of the utility. BUT it will at times not do the job with the same quality (voltage and frequency will vary more). So most likely all was working fine and perhaps due changing loads etc. the generator input went outside what the inverter considers "correct", so it disconnects the "replacement utility". Setting the inverter to "appliance" vs "UPS" may help with voltage fluctuation from the generator but if frequency is a problem I do not know if you can set that on the axpert. NOT comparing makes etc. but the multiplus inverter/chargers have an option where you can tell the inverter to sort of ignore the quality of the incoming AC power which is at times used if a generator+inverter combo seem to struggle to get along Quote Link to comment Share on other sites More sharing options...
Coulomb Posted July 12, 2020 Share Posted July 12, 2020 (edited) On 2020/07/10 at 5:34 PM, Rusti said: This worked fine and my battery charged to about 80% before the utility light started flashing and charger circuit light when off and the battery obviously stopped charging. This could ironically be due to a lack of load. When the battery gets to about 80% (I assume per the battery BMS, the inverter's SOC reading is useless for LFP batteries), the load from charging will go down, so then the generator's governor is reacting to every small load that comes on or goes off, and and being a mechanical system, it can't respond instantly. So the voltage and frequency (from the engine's fluctuating RPM) will be chopping around, and the Axpert has trouble locking on to it. When this happens, it declares the AC source as dodgy, the AC-in icon starts flashing, and the inverter-charger stops using AC-in. A generator with an inverter built-in can generate crisp 230 V sine waves with a crystal locked frequency; these are the types of generator that Axperts prefer. But I get that it's not convenient to swap generators at this point. If you have a moderate, constant load like an EVSE, room heater or inverter based air conditioner (a normal A/C will cycle on and off, not what you want), then you could attempt to schedule those loads for when the battery is nearly full. Otherwise I think you'll just have to put up with only charging to 80% from generator. I believe the inverter-charger will switch to battery mode when it's had enough; just turn off the generator at that point, wait till say 60% SOC and then turn it on again. It's a pain, but that's the way it is. I don't see any of your settings that would affect generator operation. On 2020/07/10 at 6:43 PM, introverter said: Setting the inverter to "appliance" vs "UPS" may help with voltage fluctuation from the generator but if frequency is a problem I do not know if you can set that on the axpert. I suspect that the OP has a King model (or equivalent; they have such different names for the same thing). These internally have that setting, but for whatever reason it doesn't appear in the configuation screen (it's not user settable). The default is APL mode (most forgiving, slowest changeover speed). Edited July 12, 2020 by Coulomb Quote Link to comment Share on other sites More sharing options...
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