A Forum run by Enthusiasts of MidNite Solar

Charge Controllers and Clippers => The "Classic" charge controller => Topic started by: asdex on July 28, 2018, 08:11:04 PM

Title: Classic not reporting correct SOC
Post by: asdex on July 28, 2018, 08:11:04 PM
Hi, I haven't been able to get my classic to report my battery SOC correctly. When it says 100% the batteries can be 1200. I have the up to 1260 now but I wanted to use the Classics SOC to switch a relay when the batteries are fully charged. I have tried adjusting the efficiency but that hasn't helped.
Any ideas?
Thanks,
Title: Re: Classic not reporting correct SOC
Post by: dgd on July 28, 2018, 10:53:51 PM
The problem is the SOC % reported by the Classic/wbjr combo is at best only a reasonable estimate of the battery actual state of charge.  There are just too many variables involved to depend on a particular SOC reading
I always find it interesting that the SOC jumps to 100% on moving from Absorb to Float despite the last Absorb SOC at less than 95%. Worse if there are several days without reaching Absorb and SOC is in the 85 to 90 range.
Dgd
Title: Re: Classic not reporting correct SOC
Post by: ClassicCrazy on July 29, 2018, 12:18:51 AM
Quote from: asdex on July 28, 2018, 08:11:04 PM
Hi, I haven't been able to get my classic to report my battery SOC correctly. When it says 100% the batteries can be 1200. I have the up to 1260 now but I wanted to use the Classics SOC to switch a relay when the batteries are fully charged. I have tried adjusting the efficiency but that hasn't helped.
Any ideas?
Thanks,

You may need to tweak the capacity as well as the efficiency . Are you using Whizbang and ending amps to terminate the absorb cycle or just using time ? If your batteries are going to float ( and that makes them go to 100% SOC)  early before the batteries are fully charged according to your hydrometer then you either need to lower the ending amps or set a longer Absorb time ( or make sure the absorb time is not set too short if using ending amps because which ever comes first is what terminates Absorb. )

Larry
Title: Re: Classic not reporting correct SOC
Post by: boB on July 30, 2018, 12:10:29 AM
Quote from: asdex on July 28, 2018, 08:11:04 PM
Hi, I haven't been able to get my classic to report my battery SOC correctly. When it says 100% the batteries can be 1200. I have the up to 1260 now but I wanted to use the Classics SOC to switch a relay when the batteries are fully charged. I have tried adjusting the efficiency but that hasn't helped.
Any ideas?
Thanks,

What is the 1200 and 1260 ?  Is this a specific gravity reading ?

boB
Title: Re: Classic not reporting correct SOC
Post by: asdex on July 30, 2018, 09:27:22 PM
Yes that's correct. The specific gravity.
I was charging the batteries according to the SOC value on the classis but found it to be well out therefore seriously undercharging the bank.