Inverters not accepting generator power

non-EV Solar, Wind and other renewable power sources
non-EV batteries and other energy storage stuff
Forum rules
Important!
This forum is for discussion of Non-EV matters.
Post Reply
Greg Mill
Noobie
Posts: 2
Joined: Fri, 01 May 2020, 17:30
Real Name: Greg

Inverters not accepting generator power

Post by Greg Mill »

Morning Everyone

I have 3 Axpert Kings (OG-5.48) inParrallel with a 18kw Pylontech Battery with solar panels working in parrallel, its backed up with a 3ph diesel generator and I'm using the inverter dry ports to start the genset when the battries need charging on overcast days or at night, however the inverters are showing me the in coming power but refuse to accept the generator voltages, I have managed to get them to work if i unplug the BMS cable but that the results in the inverter giving me a (04) LOW VOLTAGE warning on the master, I then do not get the full usage of the charge stored. If i plug the BMS back the inverters do not accept the charge from generator again and the relays click between the inverters and send surges towards my load.

I have spoken with suppliers of the inverters and they seem to have run out of answers, I've spoken with the generator people and from there side everything seems in order.
Reading the comments in discussion on this forum I have noticed mention about setting 3 needing to be on APL however i don't have that setting on my inverters and it seems I might have been supplied the incorrect firmware by the suppliers, the WATCHPOWER was out of date from the beginning and the provided a link to the version I'm currently using.

Any advice at this stage would be greatly appreciated as the suppliers don't seem to know how to fix the issue.

Thanks in advance!
Greg
User avatar
brunohill
Groupie
Posts: 176
Joined: Thu, 08 Feb 2018, 22:32
Real Name: Phil
Location: Wangaratta

Re: Inverters not accepting generator power

Post by brunohill »

You could try putting a load on the generator between it and the inverter. Maybe 1,2 or 3 150 watt flood light bulbs and see if that makes it happy, although that wastes a lot of power.
User avatar
coulomb
Site Admin
Posts: 4319
Joined: Thu, 22 Jan 2009, 20:32
Real Name: Mike Van Emmerik
Location: Brisbane
Contact:

Re: Inverters not accepting generator power

Post by coulomb »

brunohill wrote: Mon, 04 May 2020, 19:46 although that wastes a lot of power.
It's quite possible that if the bulbs are needed, they are only needed for less than a minute, so the wasted energy is minimal. I would use a balanced load, so three similar loads actives to neutral, or a single three-phase load. Once the inverter accepts the generator and loads it up, the temporary loads should not be needed (unless your loads all go to zero I guess).
Nissan Leaf 2012 with new battery May 2019.
5650 W solar, 2xPIP-4048MS inverters, 16 kWh battery.
1.4 kW solar with 1.2 kW Latronics inverter and FIT.
160 W solar, 2.5 kWh 24 V battery for lights.
Patching PIP-4048/5048 inverter-chargers.
Greg Mill
Noobie
Posts: 2
Joined: Fri, 01 May 2020, 17:30
Real Name: Greg

Re: Inverters not accepting generator power

Post by Greg Mill »

Should i put a light on each phase of the generator so all the phases have a load? Out of curiosity why are we doing this?

I don't mind running the lights for the entire time that the generator is on, or should I use a time delay timer to turn them off if the generator accepts the load?

Greg
User avatar
coulomb
Site Admin
Posts: 4319
Joined: Thu, 22 Jan 2009, 20:32
Real Name: Mike Van Emmerik
Location: Brisbane
Contact:

Re: Inverters not accepting generator power

Post by coulomb »

Greg Mill wrote: Mon, 04 May 2020, 22:14 Should i put a light on each phase of the generator so all the phases have a load?
I suppose all you really need is a mechanical load for the petrol/diesel engine. So one phase should be OK.
Out of curiosity why are we doing this?
Why balancing the load, or why the load at all?

Balancing the load is good to make the best use of the conductors. They all have limit, and if you spread the load evenly, you get more power out at the limits.

The load is to settle the engine. They seem to work less smoothly in no load conditions, and this results in distortion of the generated waveform, which the inverter then rejects. With a little load, they hopefully run smoother, and hopefully the waveform is them acceptable to the inverter.
I don't mind running the lights for the entire time that the generator is on, or should I use a time delay timer...
If you have some use for the light or heat from the load, by all means leave it on. It's just that if you don't have a use for it, it's wasted fuel, which costs a lot more than grid power, and infinitely more than solar power :D At least, marginal solar power is free, if you have the capacity.
Nissan Leaf 2012 with new battery May 2019.
5650 W solar, 2xPIP-4048MS inverters, 16 kWh battery.
1.4 kW solar with 1.2 kW Latronics inverter and FIT.
160 W solar, 2.5 kWh 24 V battery for lights.
Patching PIP-4048/5048 inverter-chargers.
antiscab
Senior Member
Posts: 2700
Joined: Mon, 26 Nov 2007, 05:39
Real Name: Matthew Lacey
Location: Perth, WA

Re: Inverters not accepting generator power

Post by antiscab »

what if you used a battery charger as the load? there's heaps of cheap 48v chargers out there - and then it doesn't matter if you leave it on the whole time the generator is running or not
Matt
2017 Renault zoe - 25'000km
2007 vectrix - 156'000km
1998 prius - needs Batt
1999 Prius - needs batt
2000 prius - has 200 x headway 38120 cells
T1 Terry
Senior Member
Posts: 1155
Joined: Thu, 30 Sep 2010, 20:11
Real Name: Terry Covill
Location: Mannum SA

Re: Inverters not accepting generator power

Post by T1 Terry »

The last 48v system we installed has a Kubota diesel generator and it plays up big time. The input voltage will steadily climb up to 270vac and then the inverter rejects it, the generator drops back to 220vac and the whole cycle starts again. This fix in this set up is to turn the coffee machine on, a big resistive load in the form of the heating element and a few smaller loads for the pump and electronics. This settles the generator output, the inverter switches over to put the power from the generator through to the house power and switches from an inverter to a battery charger. As there are 2 x PIP 5048 involved, the charging load is relatively high although I has set them back to 30 amps per unit so sudden house loads don't exceed the generators capacity. My advice would be to switch the electric hot water element on with the generator start up or when you switch the generator to load if you have a warm up period first. Run it on a timer for say 20 mins to ensure the frequency and voltage has stabilised, then watch to see if the inverter stays linked in to the generator supply.
The reason why this happens, the flywheel on a diesel engine needs to be heavy enough to smooth out all the changes in speed, the big industrial stuff and the old diesels had huge flywheels, but a lot of the modern stuff doesn't. These continually changing speeds create a multitude of frequencies all on the same output and that freaks out modern electronics resulting in an unstable voltage and a mass of frequencies that are not the 50hz the inverter is looking for, so it simply ignores the input because the supply is not the 200vac to 250vac @ 50 hz it requires to meet the filtering on the input circuit.
Many moons back we had a similar problem and tried to open up the range of voltages and frequencies the inverter would accept, it let the smoke out a mth later so we didn't try that again.

T1 Terry
Green but want to learn
Post Reply