Charge rate for batteries

[asdex]

Hi, just wanted to check that I'm calculating this right. My battery specs say bulk charge is 7.35 volts per six volt battery. I have two sets of four batteries in series then paralleled together for 24 volts. Would I set the bulk charge rate in the Classic at 29.4 volts? absorb at 29.4 volts and float at 26.4 volts?
I have just got these specs as our batteries are branded differently so haven't checked the Classic yet for time of absorb but I think I remember seeing this in the menu.
Thanks,

[Westbranch]

you only need to set the Absorb and Float voltages, the Classic takes care of the rest.  A good starting point is 2 hrs for Absorb, if they don't perform to spec then increase the time...

hth

[Vic]

Hi asdex.

Most Solar chargers do not have a setting for Bulk voltage (this is customarily seen on On-Grid battery chargers),  so you do not need to worry about a Bulk voltage setting.

29.4 volts should be fine for your Absorption voltage,  as this IS equal to 7.35 V per 6 V battery.   Be certain to set the Temperature Compensation value in the Classic's Temp Comp page in the Charge menu  -- it appears that your batteries need a setting of about --3 mV per cell.

AND,  the Absorption time required by batteries is directly dependent upon the Depth Of Discharge DOD) experienced in the previous discharge cycle.  Two hours may not be a bad place to start.  You can set the Absorb time in the Charge menu,  in the Time page.

Measuring the Specific Gravity of each cell with your Hydrometer is the best measure of how well your charge parameters are working to charge your battery bank on a given day.

The battery data notes that the Target SG for fully charged batteries is 1.270.

Vic