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Battery talk (A place to discuss any and all battery technologies where the discussion may not fit into other topic areas) => Lead Acid (Sealed and flooded) => Topic started by: svencool on June 17, 2017, 02:21:34 PM

Title: 12v to 24v
Post by: svencool on June 17, 2017, 02:21:34 PM
Today I went from 12v battery bank to a 24v battery bank. Question is I use to have the BULK and FLOAT setting in the classic set to the manufactures 12v specs. So now that they are wired in series do I basically double those settings? BULK was 14.5v and Float was 13.5v. So now would I do 29v on BULK and 27 on FLOAT?

Thanks Mike
Title: Re: 12v to 24v
Post by: Vic on June 17, 2017, 05:07:20 PM
Hi Mike,

YES,  if those settings were working well on the 12 V system,  you should try just doubling the Absorb and Float voltages as a starting point.

Assume that the batteries are identical  and same ages.

The Classic uses the term,   Absorb for the Absorption voltage setting.   Some other CCs do use the term Bulk for this setting.

Vic
Title: Re: 12v to 24v
Post by: svencool on June 17, 2017, 05:37:53 PM
Yes I have a classic 150 and now I'm running a 24v system I also am using a Samlex inverter. It seems that going from 12v to 24v that I get more run time. Maybe not! Its just the first day. I just have to learn how to tweak the classic now.... When I was running a 12v system I was using about 300w @ 19amps. Now on 24volts It seems to be using 260w and about 9-10amps....
Title: Re: 12v to 24v
Post by: ClassicCrazy on June 17, 2017, 10:54:43 PM
Quote from: svencool on June 17, 2017, 05:37:53 PM
Yes I have a classic 150 and now I'm running a 24v system I also am using a Samlex inverter. It seems that going from 12v to 24v that I get more run time. Maybe not! Its just the first day. I just have to learn how to tweak the classic now.... When I was running a 12v system I was using about 300w @ 19amps. Now on 24volts It seems to be using 260w and about 9-10amps....

Watts will be comparable on 12v or 24v . Amps will be different on 12v and 24v even if the watts were the same.
Use this equation  Volts x  Amps = Watts.
so 12v x 2 amps = 24 watts
     24v x 1 amp   = 24 watts

For your example since there is some missing information ( exact voltage)  I will just assume

12v x 19 amps = 228 watts
24v x  9 amps = 216  watts

Pretty close to the same - and since your voltages were probably higher than 12v or 24v that would have brought the watt up if you used the exact voltages in the example above.

Larry
Title: Re: 12v to 24v
Post by: WizBandit on July 03, 2017, 03:21:39 PM
Be advised, the Classic asks you verify the battery voltage if finds during the setup Wizard (VMM).  This is where the Classic sets internal the number of cells to use for T-Comp if a BTS is installed.  Just changing from 12v setting to 24v without doing a VMM will cause T-Comp to be wrong as a 12V battery has 6 cells and a 24v has 12 cells.

If you have the Local Ap running you can just set the battery in there to 24V with out a VMM and the Classic should update the register that holds the cell count.