absorb time question

[kauaisolarman]

I have a Kid controller without any WBjr  and i have the absorb time for 240 min.

my question is if the controller only gets 100 min of absorb time on day 1 of charge will it only put in the extra 140 min needed to finish absorb charging on day 2? assuming there are no loads and you are only charging the battery?

just want to know if the absorb time gets reset every night or only after a complete charge has taken place (full 240 mins)?

thanks

[ClassicCrazy]

The Absorb time starts when the voltage gets to absorb voltage setpoint and continues on until time is up and then it goes to float.
I think if it drops back to Bulk during absorb  it starts the timer all over again .
The next day it would start all over again.

The Whizbang is nice because you can determine your ending amps and it will end absorb when it gets to end amps setting ( or absorb time if that comes before end amps ).
Larry

[Vic]

Hi Kauai..,

In addition to what Classic Crazy Larry said:

Each charge day is a new day,  with no regard to what has been the charge history   ...  the Absorg stage begins anew,  and will end with either the Absorb timer counting down to zero,  or EA having been satisfied.

As Larry mentioned,  having  End Amps  using the WbJr and a Shunt is ideal,  because this represents a full-charge (when properly set),  verses having a fixed time that repeats each day,  irrespective to the Depth Of Discharge that the battery experienced in the previous discharge.

IMO,   Vic

[kauaisolarman]

seems odd as i though that would overcharge the battery?

for example.  I have a 48V aquion battery that comes with pretty much 0 charge. 

when i hook the battery up to the Kid controller the controller starts to bulk charge, then by about 2pm absorbtion stage hits.  however, since it is so late in the day absorb only lasts for about 100 minutes (leaving 140 minutes of absorb time left to fully charge battery).  the next day when the absorb cycle starts and lets say it puts the full 240 mins of absorb in the battery this would equal to 340 minutes of absorb (100min day 1 240 min day 2) total and is way over the battery manufacturers spec.

again this is assuming there is no loads on the battery and just needs to be fully charged and not overcharged.

thanks for the input

[dgd]

The Absorb time starts when the voltage gets to absorb voltage setpoint and continues on until time is up and then it goes to float.
I think if it drops back to Bulk during absorb  it starts the timer all over again .

When in Absorb, if the charging drops back to Bulk then into Absorb again,  the Absorb timer starts again where it got to previously.
It does not restart all over again. If it did you may risk battery overcharging.
Its a better idea to use the WBjr with EA Absorb termination.

dgd

[ClassicCrazy]

seems odd as i though that would overcharge the battery?

for example.  I have a 48V aquion battery that comes with pretty much 0 charge. 

when i hook the battery up to the Kid controller the controller starts to bulk charge, then by about 2pm absorbtion stage hits.  however, since it is so late in the day absorb only lasts for about 100 minutes (leaving 140 minutes of absorb time left to fully charge battery).  the next day when the absorb cycle starts and lets say it puts the full 240 mins of absorb in the battery this would equal to 340 minutes of absorb (100min day 1 240 min day 2) total and is way over the battery manufacturers spec.

again this is assuming there is no loads on the battery and just needs to be fully charged and not overcharged.

thanks for the input

I had never heard of those Aquion batteries before the other day and read up on them a bit.
Their specs do not list an ending amps. So you better check with the manufacturer to find out if they recommend that and what it would be. Most of us have lead acid battery experience and what you have is much different so our advice may not be suitable.

I found this about charging Aquion batteries. 
https://www.solar-electric.com/lib/wind-sun/Operational_Settings_for_Power_Control_Electronics_with_Aspen_Batteries.pdf

Larry

[mike90045]

.....when i hook the battery up to the Kid controller the controller starts to bulk charge, then by about 2pm absorbtion stage hits.  however, since it is so late in the day absorb only lasts for about 100 minutes (leaving 140 minutes of absorb time left to fully charge battery).  the next day when the absorb cycle starts and lets say it puts the full 240 mins of absorb in the battery this would equal to 340 minutes of absorb (100min day 1 240 min day 2) total and is way over the battery manufacturers spec.......

Charge controllers of any brand, have generic setpoints in them.  When you deviate from generic batteries, you inherit the risk and responsibilities of maintaining non-generic batteries.   If controllers start shipping with more charging algorithms, some Pb-H2So4 dummy is going to to try to use new settings for old batteries.   Whoopee !!

If you are going to be a trailblazer, learn to blaze trails

[kauaisolarman]

.....when i hook the battery up to the Kid controller the controller starts to bulk charge, then by about 2pm absorbtion stage hits.  however, since it is so late in the day absorb only lasts for about 100 minutes (leaving 140 minutes of absorb time left to fully charge battery).  the next day when the absorb cycle starts and lets say it puts the full 240 mins of absorb in the battery this would equal to 340 minutes of absorb (100min day 1 240 min day 2) total and is way over the battery manufacturers spec.......

Charge controllers of any brand, have generic setpoints in them.  When you deviate from generic batteries, you inherit the risk and responsibilities of maintaining non-generic batteries.   If controllers start shipping with more charging algorithms, some Pb-H2So4 dummy is going to to try to use new settings for old batteries.   Whoopee !!

If you are going to be a trailblazer, learn to blaze trails

thanks for all the input.

dont see how im trailblazing anything but OK.

just want to know if the KID charge controller is capable of doing something or not.

i understand that If i used the WBjr i could use ending amps to get a more accurate termination of absorb stage of charge, but for people without WBjr just want to see that their options are.

i'm sure if any manufacturer of any battery says that the absorb charge time is 120 mins and you absorb the batteries for 400 mins the battery will not be happy weather they are lead acid or not so i dont see how this is any different than any other set of batteries.

charge controllers come with generic settings. but thats why aquion put out the charging parameters based on the different charge controllers on the market.  no trail blazing needed the manufacturer already put down the pavement all you have to do is stay on the road.  just want to know if the Kid can keep me on that road without WBjr.

[mike90045]

OK, well, not having either a Kid or WBJr, I should stop giving you advice other than ask the vendor (Aquion ) if your gear is permissible or not.

[ClassicCrazy]

The Kid should work pretty much the same way the Classic does as far as charging using the Absorb Time. I don't see why it would be any different.

Larry

[Halfcrazy]

When a battery manufacturer specs an absorb time that is per cycle.

A day is a cycle.

So during the night you use energy out of the battery and the following day will be treated as a new charge cycle.

The Kid works like every other charge controller in that respect.

[kauaisolarman]

thanks guys.

just to clear it up i was wondering how that would work if NO load was on the batteries?

for example the aquion battery has a absorb time of 240 mins for a complete charge cycle.

a battery at 0 charge with 0 loads being charged with little watts (not much power) goes into absorb charge for 100 mins the first day of charging but does not complete a full charge cycle due to the low wattage, on day 2 the controller resets and the batteries go for another complete 240 mins of absorb completing the charge.

during these 2 days of charging the batteries were exposed to 340 mins total of absorb time.  (again assuming no loads on the batteries on the first night just trying to get the batteries to full charge with the controller and solar panels)

is this 340 mins of absorb time ok?  even though manufacturer suggest 240?

i understand that if there was enough solar power the batteries could complete a full charge in 1 day and this would not be an issure, but if not enough solar power/panels are available and it takes more than 1 day to top off a battery then how would that affect the charge?

thanks

[Halfcrazy]

My opinion is the rest through the night negates any absorb time you got the day before, BUT that said it is a simple matter to install a WBjr and determine the End Amps of the battery. This way if you have batteries and no loads you can terminate an absorb charge based on time OR current.