battery charger amps spiking while running off generator

[rick911]

as the title says, I noticed that the charging amps while running the charger off of the gen to recharge batts was spiking fron lets say 12amps to 25amps. it does this every 3 seconds or so....it doesn't keep a steady flow like when its running off shore power. anyone know what might be the problem if that is indeed a problem(I assume it is tho). charger is a promatic 30-3, gen set is kohler model 5e 3600rpm. I just purchased the boat 1 month ago.

[mmwjr]

Welcome aboard.

If the charger is steady when on dock power and this only happens when the genny is on I would suspect that the genny's output is not clean 120 VAC.

[rick911]

Originally Posted by mmwjr

Welcome aboard.

If the charger is steady when on dock power and this only happens when the genny is on I would suspect that the genny's output is not clean 120 VAC.

yea that's what I seem to be getting....sine wave not steady. the gen runs everything on the boat just fine, only thing that seems to be having a problem is the charger. wonder if a newer charger would fix that or if there is something that could be done to the generator to get a steady power flow

[mmwjr]

I would have the generator's output checked first as it may have an internal issue. Most other loads are not that sensitive to an unclean sine wave.

[shrew]

I'd have the genny serviced first. Frequently, they'll hack the output by raising the idle screw. This is not how to tune a genny. They are often way off. Then talk to your certified Kohler Service rep about what you're seeing. It sounds like the genny is 'hunting' a bit. The genny should ramp up/down based on load. The charger will ramp up/down based on available amps. They sound like they're both being very polite to one another.

[rick911]

quick update, figured out that putting load on the gen, like running the a/c, will make the charger work properly. needle stays steady just like it should.