Forum Discussion
ken_white
Oct 10, 2014Explorer
pnichols wrote:
Ken,
You're right on with this comment - however many outside of the electrical engineeing world will have no idea what this means.
I'm well aware of feedback loop theory and practice, but completely ignored it a few years ago in our RV and went for broke. Our RV has a good old Parallax converter in it which has been rock solid for years. To speed up drycamp charging a bit, I took an old Sears 2/10/50 charger and tried paralleling it with the Parallax. I set the Sears to it's 50 amp "engine start" position and watched the current flow from it to make sure it wasn't high enough to destroy itself after too many minutes. The Sears contributed about 50% more to the converter alone's charging current and was well below what would burn up the Sears on it's meant-for-short-term-use-only 50 amp engine start setting.
These two power supplies - just by pure luck - work well together for dumping more current into the RV's AGM batteries while the genny is running. Of course I didn't look with an o'scope for oscillations, because a couple of 100 AH batteries as a load (acting as a huge capacitor) pretty much dampens out instability oscillations at any frequencies of concern.
I got the idea to "just try" the multiple power supplies in parallel from pianotuna - who I believe had started using this approach in his RV for battery charging many years ago with good results.
I wouldn't have thought you would have a problem with a regular battery charger since they are basically an open loop fixed voltage/current source.
I do try not to speak EE so much, but sometimes it just slips out.
Sorry,
:)
About Technical Issues
Having RV issues? Connect with others who have been in your shoes.24,341 PostsLatest Activity: Dec 04, 2025