New AGM Batteries

[BigAl.NZ]

We had to splash on some new batteries as the old Gels we had died.

The new ones are Full River DC224-6 in series.

If I read the spec sheet right bulk and abs (@20 deg C) are 14.82v. This seems quite high as my Gels were only 14.2v.

Does this sound right? (the 14.82v). Just checking before I hook up the charging sources (Alt+Solar+Inverter/Charger - Balmar/Victron).

Cheers

AG

[Wotname]

Yes, it sounds right - assuming you have temperature compensation set correctly on the charger. Temperature compensation should be set at -4mV / °C / cell .

Without temperature compensation, use 14.7V instead of 14.82V.

Generally, AGMs require higher charge voltage than gels.

[BigAl.NZ]

Awsome - thanks

[Stu Jackson]

Gels have ALWAYS had lower charging voltages.

[smac999]

Gels hsve really low charging which is why they are not used any more. Everything needs to be custom setup. (Alternators etc) Where as agms can drop into a normal system.

That is pretty high for agm though. Normally 14.4-14.6 is more standard. Flooded are up to 14.8v though. But go with what the sticker says.

[BigAl.NZ]

Actually one thing I have realised - my MPPT Smart Solar allows me to program the volatges for absorption etc - and it has temperature compensation.

So when I enter in the absorption voltage - which one am I entering? The 20 deg C voltage or??

The manual kinda hints it might be 25 deg C : https://www.victronenergy.com/live/v...-solarchargers (about half way down near the temp coefficent graph where it talks about base temp)