Group 27 AGM mid life performance report

full_mosey wrote:

BFL13 wrote:

...
I just went out and checked my AGMs which have been on 13.7 since last evening after getting 70AH back in from being 80AH down. Say 94% SOC at the time. That's when I dropped the voltage to 13.7 from 15ish.

Are you sure that 13.7 is the correct float Voltage. My MS TS 45 PWM is floating my AGMs right now at 13.87V. The battery temperature is 41F.

I just checked weather.com and see Victoria is 35F and rain. Is your AGM warmer than 35F.

HTH;
John

Oops it is 32F and snow just now :( Rats, hope it rains off so no shovelling.

You are correct, I have did not set the 13.7 up for the temp yesterday. I can do that today once I finish this part up. At the moment I am at 15.2v (14.8 at 77F) for both battery and charger and the bank is accepting 0.3 amps by Trimetric. (Down from 0.4 amps earlier) AH is going up very slowly!

I have the compensation chart Mark posted, which says 13.6 at 77F should be 14.2 at near freezing. I will set the charger to 14.2 instead of 13.7 this time.

Scroll down to the chart
http://forums.trailerlife.com/index.cfm/fuseaction/thread/tid/26669731/srt/pa/pging/1/page/1.cfm

Thanks for the reminder!

Mark asks what about battery temp vs ambient temp? The ADJ charger does not have a temp probe on the batteries. But after you stop the high voltage charge, and go to Float batt temp drops a bunch. What are you supposed to do? Beats me! Anyway I will set 14.2 instead of 13.7. Sometime later I will disconnect and after a few days get a resting voltage to see if that matches 100% SOC. (Which in this case is a fairly wide "zone" so not exactly helpful if you are picky.)

http://www.hespv.ca/hesproductspecs/HES/Stark_Battery_TD_ENG.pdf

BTW, it is totally embarrassing for it to be so cold here in February. How can we **** a snook at those poor guys Back East when it is like this? Global Warming must have been cancelled for this year. Where is Al Gore when we need him? :)

EDIT some more:

After dark, 76.4 AH, so up a little. 15.2v Tri showing 0.3/0.2 amps so near 0.2 (0.1 each where LY thinks is near 'full') dropped to 14.2v for the night. We'll see tomorrow where we area at.

It seems rv.net doesn't like male chickens. or what you do with rifle bolts. Oh well