I did a search and read through some of the past postings on this, but I am still not ‘getting it'. Can anyone help me understand how to set the minimum absorb time correctly? What am i basing this minimum absorb time setting on? I have the maximum absorb time set based on the ballpark information provided by the battery manufacturer. Right now I have it set at 45 minutes as the minimum and 5 hours for the maximum. Thank you.
I am not quite following what you mean you have Absorb time set to minimum and maxium - there is only one time setting in Absorb Time
Using ending amps to terminate the Absorb cycle is the best way to do it for lead acid batteries ( and some other types too) . You need a Whizbang to do this . So when using the ending amps you set the Absorb timer for the longer time period and then watch it to make sure it is long enough for the batteries to fully charge and ending amps to do its job.
Info below is from the Midnite Solar Knowledge Base
http://www.midnitehelp.com/
Frequently Asked Questions
All Categories » CLASSIC CHARGE CONTROLLER - Features and Programming
CLASSIC - ENDAMPS - How do I figure what ENDAMPS should be?
Lets first tell you what ENDAMPS is...
ENDAMPS is the current the Lead-Acid type battery will "draw" from the charging source when it is 100% charged and can take no more charge. It is this point if the current is not reduced the battery electrolyte and the battery will heat up. Too much and things can get ugly very fast.
The Classic has the ability to terminate the Absorb cycle using Whizbang JR as the ENDAMPS source. For this to work most systems will require a SHUNT and the WBjr option. The WBjr is a current measuring option for the Classic and KID charge controllers. It sends data on the amps in or out of the battery, it is important for things to work to have this and the shunt installed properly.
How to figure what YOUR battery needs for ENDAMPS.
First. lets look at what effects ENDAMPS.
#1 - Battery age
#2 - Battery condition
#3 - Battery type (Flooded, GEL, AGM, other)
#4 - Some battery manufacturers have this number for you, but be warned, for a NEW battery
The Best way to figure out YOUR Battery ENDAMPS is this way:
Take a day, turn off all LOADS while testing for ENDAMPS.
Set ABSORB TIME to something high, like 8 hours.
Remember what your time was, write it down.
Let the Classic (or KID) get to absorb, then come back after the time your wrote down has passed.
Lets say default 2 hours you are back.
Get a notebook, mark off lines every 10 minutes for about 2 hours, 12 lines like this:
:10
:20
:30
:40... and so on.
Go to the WBjr page, 3rd page on the STATUS BUTTON and watch the amps.
They should be a positive number between 1 and 20 amps or so, depends on your battery total Ah rating.
Write down the AMPS every 10 minutes for 2 hours.
You should see a point where the AMPS do not drop any further, your ENDAMP setting will be this number plus maybe 1/2 or 1 amp.
You should set your absorb time to be only about a hour longer that normal. ENDAMPS will drop the Classic to FLOAT at exactly the setting you put in. If everything is right, your battery will always go to float at 100% SOC.
You may need to do this every 6 months to a year as your batteries age.
Help Topics: Charge Controller - CLASSIC, Charge Controller - KID
Last updated Wed, Aug 9 2017 12:58pm
-----Larry
My screens show min and max absorb times which are both setable in minute and hour increments.... photo attached.
Quote from: alyaz on October 06, 2018, 12:39:24 AM
My screens show min and max absorb times which are both setable in minute and hour increments.... photo attached.
I ~think~ you may have older firmware ? The Classic used to have a different absorb algorithm, sort of....
I'm having a hard time even remember that version now but Absorb should really go for a preset amount
of time that the battery manufacturer recommends to lower the chance of sulfating the plates. The variable
absorb time was meant to reduce over-absorbing and absorbing every day if it wasn't discharged much...
Like if the system is never used but receiving sun every day. That would prematurely boil the water away if
nobody is there to maintain it.
That was the reason we changed it to a fixed amount of Absorb time but also added the ability to not Absorb
every single day. Skip Days. There's a bit more to the story but that's the basics.
Please check the software version and date. That information should be in the main status menu screens. Access
by pressing the status button until the Classic version screen comes up.
boB
Thanks. The last time I checked you couldn’t do firmware updates with a Mac though, correct? Could I set min and max both to the 5 hours?
Quote from: alyaz on October 06, 2018, 01:25:11 AM
Thanks. The last time I checked you couldn’t do firmware updates with a Mac though, correct? Could I set min and max both to the 5 hours?
Well, you ~can~ upgrade with a Mac but it takes some Python code which is similar to the way it is done in Linux. I'm not sure if that
method and code is still on our site ?
Yeah, setting the min and max times near to each other should work fine. If it ain't broke, don't fix it.
boB
I have a line on an older IBM laptop today. Sorry for all the questions...
1. Is that Youtube video that boB uploaded there still a good source to use even though it is somewhat dated? https://www.youtube.com/watch?v=QKhDxoBcCXw
2. I get the latest firmware updates from - correct? https://www.midnitesolar.com/firmware.php?firmwareProduct_ID=1
3. Just use the latest version - which seems to be working well?
4. Any other advice appreciated... thanks.
5. Is loading the app a worthwhile thing to do for firmware upgrades or is it meant more for monitoring? Is adding the app just going to complicate things for a dufus like me at this point?
...wow just read the instructions in the firmware update... a 'hardware version of a factory restore’ instructions looks scary in of itself! So can you do the ‘quick start’ process versus the ‘factory restore’ version after the firmware update?
Al, I believe you are somewhere in the Gulf Islands... on your old set of batteries, how long did it take you to get to Absorb? that is a good number to start at, if not there on the new set just up the time by 1/2 an hour till you get to Absorb... you may have to adjust again as the sun drops , ie closer to the dead of winter... then lessen it as the sun rises.
cheers
thanks. i have all the charge parameters figured out for when the new batteries arrive ( ??? ) but in the mean time i’m thinking about getting the Classic firmware updated. just trying to make sense of it. :-)
Quote from: alyaz on October 06, 2018, 11:09:11 AM
I have a line on an older IBM laptop today. Sorry for all the questions...
1. Is that Youtube video that boB uploaded there still a good source to use even though it is somewhat dated? https://www.youtube.com/watch?v=QKhDxoBcCXw
...wow just read the instructions in the firmware update... a 'hardware version of a factory restore’ instructions looks scary in of itself! So can you do the ‘quick start’ process versus the ‘factory restore’ version after the firmware update?
No that video is obsolete the firmware download has a new installer. You connect the USB cable from the Classic to the laptop and run the EXE file and follow the instructions to update the Classic and then the MNGP. Both have to be updated. Not sure what all Win OS the new installer supports but for sure it works with WIN 10 an I believe it maybe supported on WIN 7.
After both the Classic and MNGP are updated turn the solar and battery breakers off and hold down the left and right arrow keys and then turn the battery breaker on to power up the Classic it should sense your battery voltage make sure it correct and continue and then turn solar panel breaker on.
The App is for monitoring and changing settings on the Classic. You can also save all the settings and reload them after a firmware update as settings will revert to factory default after a firmware update.
Thanks Resthome.
I put my big boy pants on and got-er-done :) Unfortunately I saw your post after I started with the old procedure, changed the port setting to 8 and nuttin. I was losing it but remembered seeing that pop up box that said port 3 on it. So I changed the port back to 3 and voila it started downloading! So I had too much and too old of info in front of me initially. However, the second one went slick. Got the updates for the units and the displays all done. Nice to not have that absorb min and absorb max screen anymore too.
Thanks everyone for putting up with me. I’m good for another 6 years now! Haha...
Quote from: alyaz on October 06, 2018, 06:18:59 PM
Thanks Resthome.
I put my big boy pants on and got-er-done :) Unfortunately I saw your post after I started with the old procedure, changed the port setting to 8 and nuttin. I was losing it but remembered seeing that pop up box that said port 3 on it. So I changed the port back to 3 and voila it started downloading! So I had too much and too old of info in front of me initially. However, the second one went slick. Got the updates for the units and the displays all done. Nice to not have that absorb min and absorb max screen anymore too.
Thanks everyone for putting up with me. I’m good for another 6 years now! Haha...
Good to hear you were able to update the firmware - I think it was the wise choice.
If you don't have a shunt installed on your system - get one along with the Whizbang and you will open up a lot more capabilities and monitoring information because you can set up state of charge SOC for good approximation of where your batteries are at.
Larry
Thanks Larry.
Interestingly I do have a new Classic and a Whizbang on the shelf, never installed...
How much more accurate is the Whizbang shunt than the Magnum shunt / ME-BMK unit? Is the Whizbang kinda the equivalent except it is for the Midnite controllers / solar side of things?
And being that I have the Magnum BMK, can you have both?
If so, I would need to change my Apollo controller out for another Midnite controller so I have all Midnite controllers, right?
So is this right?
1. Change out the current shunt for the Whizbang.
2. Swap the Apollo for another Midnite controller and then all three Midnite controllers could run to one Whizbang?
3. The Magnum BMK could also hook to it?
I have asked this stuff before, but still pretty hazy on the details... sorry.
If you have a shunt already installed in your system ( assuming it is the same type that Midnite uses) then you don't need to install another shunt . The whizbang installed right on the shunt , and you can also have some other device wires that used the shunt before still connected and using the shunt also.
The Whizbang monitors everything going in and out of the battery . So it can count the amps accurately by knowing what the loads are , how much goes in the battery etc.
I don't know about your other controllers. I guess if it was me I would have all three controllers be the same if you have them anyway. You can hook them up in Follow Me mode and yes use just the one shunt for all three Midnite controllers I believe. Seems like this was just talked about somewhere recently in the forums but not sure if it was you who were asking.
One more note on the shunt - if you look at the shunt in your system you should see on one side it only has one connection that goes to the negative battery connection. There should be no other connections to the battery negative other than this one . On the other side of the shunt are all other negative connections . So everything has to go through the shunt.
Larry
Copy thanks.
Each of my controllers run a separate solar array (each array is a different size and at slightly different orientations), so that is why I am wondering if one Whizbang can be used :-) To me it would make sense that one Whizbang could be used, with just a wire from the Whizbang to each controller, but wtf do I know... Because of the different sized and oriented arrays, I don’t think I can do the ‘follow me’ setting... but again...
Read this post
http://midniteftp.com/forum/index.php?topic=3823.msg37137#msg37137
Larry
Thanks Larry.
Al, using the WBjr connected to the last shunt, positioned immediately before the Neg battery stud, will allow all 3 CC's to let 1 be the 'guardian of the gate' so to speak as it will keep track of the Amps in and out of the battery...
Thanks. Think I will swap out the Apollo next and then plan the Whizbang 👍