Thanks to Bill Rogers, the Utterpower PMG was designed with certain voltage characteristics that has made it ideal to charge batteries utilizing the build in chargers in the better and more serious inverters like the Outbacks. We believe this is one of the primary missions for a generator in off grid living, and the unit also does a better job running a wire feed welder and other chores because we didn’t get whimpy on the voltage at 60hz. I didn’t realize just how long some of these generators run to charge batteries, but some of my customers who run long hours off grid repported that they were actually burning less fuel and getting the charging done a >lot< quicker with their PMGs VS Honda and other makes of generators. They knew this because they had been running battery plants for years to charge batteries, and at some of these sites high in the mountains when the cloud cover rolls in, there’s a lot of generator time and off gridders get real familiar with the same ole routine, when something changes, they usually recognize it in a hurry.
Some generators have such a low peak voltage that certain inverters don’t even recognize them! You can hook them up, the voltage can be present at the input of the built in charger, and noting happens! Some of the on line stores that support folks with solar power installs understand this problem well, and they sell a transformer that will jack up the voltage five percent or so, this does allow the inverter charger to work at a far more favorable voltage, but as we know that transformer is now just an additional and permanent loss in the chain of machinery that allows us to convert a BTU of energy into stored energy in those batteries. As we have discussed elsewhere, it’s really all about the cost of a KWH of energy over time, engineering in extra losses isn’t the better design. The PMG operates at the top end of the ANSI standard for voltage, and this allows this very routine task to be done with more efficiency and quicker. If you are using the far more efficient diesel engine as your prime mover, you have a great opportunity to save money as you get this job done.
It’s always interesting to read accounts from people who have years of off grid experience. Some who run PMG have little to compare to, the more experienced are somewhat amazed at how different battery charging works, and how different their equipment seems to run and sound.
Here’s one from Montana Mac I received tonight, few people have more experience running bio fuels in the Lister Types, and Mac has powered his place with Solar and bio fuels for years, following is his short email.
(MAC) Normally when I started the engine, got it up to speed and turned on the main breaker … it was obvious that there was a load on the gen head as you could hear the engine coming under load. With the PMG … the engine still responds but to a much less degree … much smoother.
The next test I ran was to turn on a florescent light in a small room which always “flickered” a bunch with the ST head and was pretty well useless unless running on batteries and inverter. With the PMG running … NO FLICKER! Needless to say … I was surprised and impressed.
I am running an Outback inverter hooked to a fair size battery bank for daily home and shop use. The Outback has a battery charging circuit that has always done a fairly good job of battery charging. However, with the PMG running the battery charging appears to be much better and appears to be putting out full current while I have always suspected that the ST head was delivering less than ideal power to the inverter resulting in less than advertised charging current. As an added benefit the engine room noise is less and the whole system “sounds” smoother.
So far … I am well pleased and excited to try some heavier loads in the shop to see how the PMG handles some wire feed welding, air compressor, etc.
I will send some pictures of my setup soon.
Thanks for another quality product, good service and your friendship