VoltPro charging curves logged.. NOW WHAT?!?!?

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everything is my personal opinions - use your brain and come to your OWN conclusions! i am NOT an 'expert'

after spending some amount of time attempting to gather test equipment, setup a test bench, and FINDING FUNCTIONAL DATALOGGERS... we have some data!!

but what does all this mean??

well im not sure.. OBVIOUSLY most people will agree that shoveling 15 volts (or more) into AGM lead acid batteries on a daily basis isnt a good idea...

i really wanted to come out and say HEY we have a solution!! simply flip that little hidden switch on the bottom of the charger and you're good to go!

BUUT.... 'magic software' has other ideas apparently...

short version - i need to do more charging runs on the test bench.

the very first run i did with the volt pro charger on its 'mk gel' charging profile (switch position 3) the batteries started charging.. but once the charger got into 'float mode' they stopped accepting a charge, and started heating up! they never got HOT to the touch.. but the charger was dumping in 2-3 amps and the voltage remained the same for HOURS!

i disconnected the charger from the batteries, then immediately reconnected it, and the charger blew thru the entire charging curve in about 10 seconds and the green light came on! hmm.. much confuse...

(it is important to note that the 'mk gel mode' still charges at 10 amps. so using this charger on older chairs, or other brands may stress the wiring / connectors)

i moved on, testing a different charger and datalogged that with no issues, then switched back to the volt pro charger again (still on the 'mk gel' profile) and this time once it got to float mode, it was charging at a VERY reasonable 760mA! (i stopped the test after 5 hours since im not really concerned about the end of the charge cycle right now)

looking at the graph for the 'mk gel' charge profile, it seems very reasonable and usable for most all brands of wheelchair batteries! BUT.. that green light WILL NOT come on, till float mode has COMPLETED!

why does this matter? here's some background info..... every other 'stock' wheelchair charger out there indicates charging is complete and the done/green/ready light comes on shortly after float mode begins. it is technically ok to use the chair at this point.. however for maximum battery service life, float mode needs to complete on a regular basis (float mode can take anywhere from 1-5 additional hours sometimes)

none of this is really an issue though - as most rehab chair users plug their chairs in overnight as they sleep.. and in most cases 6-10 hours of charging is plenty! but that green light is ALWAYS on when ya wake up in the morning! (unless youve had an extra busy day.. theres a meme out there somewhere about having to get outta bed before your chair has finished charging lol)

however the voltpro charger in the 'mk gel' mode will not turn that green light on till float mode has FULLY completed! (and sometimes it doesnt complete.. for ?reasons?)

this leads to confusion - i want a solution to this problem that wont create more problems or questions than it answers or solves!

regardless of the charger used, i've noticed that the pemobil branded VRLA GEL batteries sometimes will randomly become resistant to float mode charging, and just get warm, and never complete the cycle overnight! (this happens even without starting the cycle at a low state of charge) this has happened with my volt pro charger (in mode 1 and mode 3) also with my victron charger, and the gray upright permobil 8 amp charger!

this seems to be a classic case of "more info, is LESS info"!

the takeaway here is.. (for now) do not leave the volt pro charger connected to a chair (in 'mk gel' mode) for more than 12 hours! and also dont worry about the lights on the front of it.
oh and OBVIOUSLY don't use mode 1 that BLASTS the batteries over 30v for extended periods AT ALL!

(once again these are my personal opinions - do whatever ya want :^) i'm not a lawyer!