Honda eu1000 going into overcurrent protection with two Victron 25 amp chargers

[ezwryder]

Wondering if anyone has thoughts or suggestions on this --- There must be some factor I am not accounting for.

I have two Victron BSC 12 volt 25 amp chargers on a Honda eu1000i generator to supplement the panels while I'm at the cabin in cold weather. The first day, the generator pushed the batteries up to 97%, then went into overcurrent protection mode. Yesterday, 90%, then overcurrent. Today, 80%. If I dial back one of the chargers to output 10 amps for a 35 amp total, the generator seems okay.

I believe the generator is rated for 900 watts continuous. I know that the chargers are 93% efficient (according to Victron). Even if a charger's output voltage has risen to 14.6 at 25 amps, that is 365 watts. If I divide that by .93, my best guess is that one charger, at its max, would be demanding around 392 watts from the generator. Two chargers, would be a little under 800 watts at the max. And that's at the end of the charge cycle just before the chargers go into absorption mode. Most of the time, total demand would be under that.

I do have the ECO mode enabled, but I don't see why that would be an issue. The chargers are a continuous load, it's not like they're cycling off/on and generating surges. In the absence of any other ideas, I'll turn it off tomorrow to see if that makes a difference. I wasn't too concerned about this on the first day (97%), but now it's taking a good bit longer to get the batteries back to full.

Thanks for your thoughts.

 

[LydMekk]

Try to turn off ECO. There is always a price to pay for "ECO"...
The only way that is reducing consumption is to deliver less watts...

 

[Mattb4]

How are your battery chargers connected to the generator? If using light gauge or long extension cords the voltage drop might be an issue. Though the obvious running without Eco mode would be worth a try.

 

[RCinFLA]

Assuming the chargers have power factor correction they still will have a power factor of 0.92 to 0.97 range.

The efficiency spec of 94% is based on watts input versus watts output, without regards for power factor or corresponding current crest factor.

The inverter-generator is not liking the AC current peaks due to peak VA load from chargers.

Also be careful of all your cable and connector losses. Feel for warm wires and connections.

Inverters, generators, and transformers are really rated based on VA, not true watts.

Cheap chargers can be much worse with power factors in the 0.6 to 0.65 range. That can knock the maximum charging power from a generator to nearly half generator VA rating.

 

[ezwryder]

Try to turn off ECO. There is always a price to pay for "ECO"...
The only way that is reducing consumption is to deliver less watts...

Yes, will give that a try this morning, thanks for the reply.

 

[ezwryder]

How are your battery chargers connected to the generator? If using light gauge or long extension cords the voltage drop might be an issue. Though the obvious running without Eco mode would be worth a try.

Thanks for the reply - I chose a heavy gauge extension rated for 20 amps and installed an inlet on the side of the cabin.

 

[ezwryder]

Assuming the chargers have power factor correction they still will have a power factor of 0.92 to 0.97 range.

The efficiency spec of 94% is based on watts input versus watts output, without regards for power factor or corresponding current crest factor.

The inverter-generator is not liking the AC current peaks due to peak VA load from chargers.

Also be careful of all your cable and connector losses. Feel for warm wires and connections.

Inverters, generators, and transformers are really rated based on VA, not true watts.

Cheap chargers can be much worse with power factors in the 0.6 to 0.65 range. That can knock the maximum charging power from a generator to nearly half generator VA rating.

View attachment 191885

Thank you RC, I believe this is on the right track regarding the peak VA load. Appreciate the thoughts and the schematics. Very helpful!