Hi Arby,
Since I'm always interested in better solutions, I did a little research into the WFCO converters that you mentioned. I just want to clarify some info. The WF9855 converter is rated for 55A @ 14.4V (bulk) which works out to 792W. WFCO says that the converter pulls 12A @ 115VAC which is 1380W. They also say that they pull 950W @ 115VAC which is only 8.2A, so I don't know how much AC current is actually required to run the converter.
In any case, I'm surprised that you can run 2 WF9855 converters on a single Honda 2000 generator, even the low number of 16.4A (8.2A x 2) exceeds the 13.3A (1600W) continuous rating provided by Honda and pretty close to the 16.7A (2000W) maximum rating. I do know that the Honda and Yamaha generators can be somewhat overloaded, but pulling a consistent 3A over the continuous rating seems dicey to me. But, seeing is believing, and if you've seen it done, then maybe the specs provided by WFCO don't tell the whole story.
On my boat, the Elcon PFC2000+ charger works fine as a power supply. It has a large integral heat sink and a built in cooling fan. The charger provides a consistant 28A @ 54VDC (bulk) and if I remember correctly, has programming that will end the bulk phase when the power provided exceeds 2 times the total AH rating of the battery bank. In my case that's about 12 hours.
But I'm getting over 1500W of power coming out of the charger. The manufacturer says that the charger will pull 15A @ 115VAC (1725W) and 14A nominal (1610W). I've measured the draw with a Kill-a-Watt meter and the charger was pulling 14A @ 120VAC (1680W). Like your setup, the 14A exceeds Yamaha's continuous 1600W rating of 13.3A, but not by as much. I've run the charger at full bore from the generator for 90 minutes and everything was working fine, so I understand that ratings are sometimes conservative.
To summarize:
WFCO WF9855 (x2), output 55A @ 28.8VDC (1584W), input 16.4A @ 115VAC (1886W)
Elcon PFC2000+, output 28A @ 54VDC (1512W), input 14A @ 120VAC (1680W)
I don't see that the WFCO converters provide significantly more DC power than the Elcon (only 4.5% less output) but the Elcon takes 11% less AC current to do it.
So I wouldn't say that ALL chargers can't be used as power supplies, but I do agree that many chargers, like the Dual Pro, are not built for that duty. Certainly, the Elcon looks to be more efficient than the WFCO and therefore, has a litle more than half the heat to dissipate. I've checked and the Elcon is only warm, not hot, to the touch after more than 4 hours of bulk charging, while attached to shorepower. The charger is mounted flat against a plywood bulkhead.
I've confirmed the specs on the Elcon with my own instrumentation, I'd like to see someone verify the WFCO figures.
Fair winds,
Eric
Marina del Rey, CA
--- In electricboats@yahoogroups.com, Arby bernt <arbybernt@...> wrote:
>
> Dear Ben,
> While I can understand WFCO's position...
We've installed a bunch of them now, and have had great results. One boat has two 55a 900w converters which have been run for many hours off a 2kw Honda with no problem. I have yet to see a charger that can deliver that kind of current, save a forklift charging station. While 20a from Zivan might be fine for a little bump, it won't get you out of a jamb when you need real power. The 55a units I use in lab testing (paralleled with 100Ah batteries) have run for weeks with no problems. They keep the batteries charged up just fine when idle....
>
> I look forward to your reply.
> Be Well,Arby
>
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