AGM Battery Users. Update Your Configuration

[Lug_Nut]

AGM batteries used to be thought by their manufacturers that voltage in excess of about 14.4 volts was the maximum charge they should ever had. Over the last year they have changed their tune and want to see much higher voltage charges. This has lead to Newmar no longer installing the limiter relay and setting the chargers to AGM. They now set all AGM equipped units to "Wet Cell". I recently changed my setting from AGM to Wet. My batteries are now providing more power when dry camping.

Just thought those that got AGM's a year or so ago might want to know this.

Peter

[Doc Mark]

Thanks Peter - now some more detailed directions, please!

Mark

[TechWriter]

Quote:

Originally Posted by Lug_Nut AGM batteries used to be thought by their manufacturers that voltage in excess of about 14.4 volts was the maximum charge they should ever had. Over the last year they have changed their tune and want to see much higher voltage charges.

Who are they?

[RVDude]

"They" is Newmar and they have been suggesting this since the beginning of the year basically for all AGM installations CONTROLLED BY ePlex. I DO NOT KNOW IF THIS APPLIES TO NON ePlex AGM INSTALLATIONS. This setting change for NON ePlex AGM installations needs to be verified.

Two reasons for ePlex AGM installations - to rectify a possible BIRD issue and to match the charge profiles now suggested by the AGM manufacturers. Newmar and ePlex carefully matched charge profiles earlier in the year and found the wet/lead acid profile is a better match for the AGM manufacturers current specs. The following post has the details.

Details as to "why" are in this specific post here and the one it links to:
"Special" Relay when switching to AGMs?

Details as to how for ePlex users press and hold "PREF" until the preferences screen comes up and then change the AGM to WET or LEAD ACID using the arrow buttons - of course by using the left arrow buttons to highlight the battery type and the right arrows to change it. Scrolling down the left arrows will bring up several more pages of preferences.

[LindyT]

It's probably worth specifying which manufacturers are now suggesting increased charge rates? Lifeline still lists the same (click) and I contacted them a couple of weeks ago and they suggested the AGM profile, indicating their site lists the proper voltages and in fact, they don't recommend the wet cell profile.

I don't believe Newmar uses Lifeline (?) so maybe it doesn't apply. Nonetheless, at $1600/pop - I'm inclined to follow the advice of the battery manufacturer vs Newmar.

All that said, I don't have the ePlex, thus maybe this is a moot point.

Good info though, thanks!

[RVDude]

Lindy makes an excellent point. Newmar has also switched to Discover batteries and that also seems to coincide with Newmar's change in ePlex settings as well.