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Charge Controllers and Clippers => The "KID" charge controller => Topic started by: Eleu on August 01, 2020, 05:36:38 PM

Title: Kid Charging at wrong absorb voltage
Post by: Eleu on August 01, 2020, 05:36:38 PM
I'm charging  Trojan T105's.  Therfore,  I have set the absorb voltage to 14.8.  The kid would reach that voltage however,  even though there is enough charge amps to keep it  at 14.8 it drops top to 14.6 and is never able to reach 14.8. As an experiment, while the kid showed absorb at 14.6 I changed the abosrb setting to 15.0 volts.   The kid immediately  increased the amps and raised the voltage to 14.8 and kept it there.   Interestingly,  I also went to history under DATA and it it showed maximum voltage for today was 15.0.  I am wondering  if the kid uses volts from the whizbang, which is sitting  right next to the battery,  for charge decisions,  but displays the voltage from the battery connection  on the kid,  which is further  from the battery and might see a voltage drop
Title: Re: Kid Charging at wrong absorb voltage
Post by: Vic on August 01, 2020, 05:58:53 PM
Hi Eleu,

Are you using the Battery Temp Sensor (BTS) on that KID?
If the batteries are above about 25 - 27 degrees C,  the Absorb and Float voltages will be reduced.

With Flooded batteries,  the battery temperature will rise,  particularly during Absorb,   and EQ.

The WbJr does not communicate battery voltage,  just battery current.

FWIW,   Vic
Title: Re: Kid Charging at wrong absorb voltage
Post by: boB on August 01, 2020, 06:00:47 PM
I don't think the Kid uses any information from the Kid for that.   The WB Jr. only reports current anyway.

What may be happening is that the Kid, like the Classic, can reach Absorb, 14.8V and if the voltage should drop a bit, like that 0.2V, it would still be in "Absorb" until it goes too far below that .   This is so that if the sun drops a bit, that the battery does not get cooked by sitting "near" Absorb for too long.

But if it ALWAYS does this, then I'm not sure exactly.    I don't suppose there could be battery temperature compensation going on that is changing the charge point voltage slightly too ?

Title: Re: Kid Charging at wrong absorb voltage
Post by: Eleu on August 01, 2020, 10:21:16 PM
The battery temperature is the answer.   They were getting warm.   Learned something new!  Thanks for the quick answer!
Title: Re: Kid Charging at wrong absorb voltage
Post by: boB on August 02, 2020, 07:22:58 PM

I'm so glad you figured that one out !

Good work !