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Other MidNite Electronics => WBjr => Topic started by: coniferous on October 01, 2019, 04:52:50 AM

Title: SOC jumping to 100%?
Post by: coniferous on October 01, 2019, 04:52:50 AM
Hi guys,

wondering how normal this is...

when my batteries get full the soc jumps from 85%ish to 100%.

I Know SOC is an estimate at best, but being off by 15 percent seems really high.

I have 1000ah of AGM batteries and right now the efficiency is at 99%. i hesitate to set this any higher, nothing is 100% efficient. Is there something wrong with my setup?
Title: Re: SOC jumping to 100%?
Post by: FNG on October 01, 2019, 08:51:33 AM
So the first thing is the jump is related to the transition to float, We "Assume" that if the classic goes to float the battery is full. So based on efficiency being set at 99% I am assumign you have absorb time or voltage set to low. Have you asked the battery manufacturer for those values and set them accordingly?
Title: Re: SOC jumping to 100%?
Post by: coniferous on October 01, 2019, 09:11:01 AM
Yup, I looked at the white paper for my batteries (https://www.usbattery.com/wp-content/uploads/2018/07/usb_agm_31_DATA_2018.pdf). I'm also using end amps with the WBjr. Right now end amps is set to 10 (1% of 1000ah).

Absorb voltage is set to 14.7.

Title: Re: SOC jumping to 100%?
Post by: coniferous on October 01, 2019, 09:18:49 AM
oops, sorry. 14.8 is the absorb voltage.
Title: Re: SOC jumping to 100%?
Post by: coniferous on October 01, 2019, 11:08:08 AM
I think I may of (Possibly?) figured it out.

I had ending amps set to 10, but I also had the timer set to 3.5 hours. I figured that was longer then absorb should last... but perhaps not. I'm going to set it to 6 or 7 hours to see when the amps plateau out and change my ending amps to that. Hopefully then the charge will be closer to 100%.

Does that make sense to someone who isn't a FNG? ;)
Title: Re: SOC jumping to 100%?
Post by: FNG on October 01, 2019, 11:28:42 AM
Yes that big of a battery may very well need a longer absorb time, 1% may also be too high on your end amps but try one thing at a time