Solar charge controller setting for AGM battery

[Stevievee]

Hi,

Any advice on this would be most useful! I am upgrading my solar set up and need some help on solar controller settings. I have a new 150w panel, with a Renogy Rover cc, charging a xtreme 200ah xr3500 battery. As this is an AGM battery I believe I am able to change the settings manually on the cc to meet the needs of AGM charging, but what should these be? I searched everywhere to try answer my own question, but am getting baffled with lots of different information! Something in layman’s terms would be great! Thanks

[g8dhe]

Normally there is a menu of battery types you select the right battery type from it. There isn't a single parameter as it depends on time/current/temperature, basically once the battery is classed as full then the charging voltage is dropped to the float voltage. Be aware however that if you also have a Split Charge Setup then all the benefits will be lost as the alternator doesn't know about AGM batteries and simply keeps blasting it with 14.4v (approx) all the time your driving!

agm-battery-charging-stages-graph3.png (36.58 KiB) Viewed 4029 times

[Stevievee]

Thanks for the reply. I think the Renogy solar charge controller have prefix of Lead, Gel or flooded as options with lead and flooded having equalisation as part of the charge sequence.
I do have a split charger, but I thought that would never be able to fully charge an AGM battery? Due to this I also have a Noco Genius 10 (with specific AGM setting) that I plug in when at home or when on EHU.
Should I put an isolation switch in, to disconnect solar when driving as to not charge from 2 sources at the same time?

[Stevievee]

Probably don't need the split charger. Having solar, then smart charger on EHU. Very rare we wild camp to be fair!

[g8dhe]

Which specific charge controller do you have they all have the Rover designation! I was going to look to see if there was a User Manual.
If it really doesn't have AGM in the menu then to be honest you would be better off using a standard flooded LB which is more robust about charging requirements, otherwise you will find that while an AGM will work your won't get the lifetime you expect by which time its too late to return under warranty! AGM's were designed for things like Golf carts, wheelchairs etc, where they have a specific charger for them and a nice steady charge/discharge pattern including a deep discharge rating. If the Solar controller doesn't support AGM, the Alternator doesn't either, and most EHU chargers are set for float charging only. So you won't at the end of the day get a better performance but you will pay a premium for the battery!

[Stevievee]

It's: Renogy 20A MPPT Charge Controller, 20 Amp 12V/24V DC Input MPPT Charge Controller Auto Paremeter Adjustable LCD Display Solar Panel Regulator fit for Gel Sealed Flooded and Lithium Battery

[Stevievee]

The Noco I have bought will provide a full AGM charge with Solar 'topping up' in between?

[g8dhe]

The Renogy manual has Deep Cycle Sealed which is effectively the same as AGM batteries.

[Stevievee]

This is what the battery manufacturers sent about charging, saying all the info is on here... Could be written in German to me! Means nothing!!

[g8dhe]

Just choose "Deep Cycle Sealed" for the battery type and that is all that should be necessary, it will (according to the manual) adjust the parameters itself over a few charge/discharge cycles.

[Stevievee]

You have been REALLY helpful Geoff. Thank you, it's very much appreciated!