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WBJr and KID - always 100% SOC

Started by keith@keithayork.com, August 09, 2021, 11:47:50 PM

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keith@keithayork.com

Hi - if this has already been covered I apologize.  I've seen some threads that were close but not close enough.  Bought a liveaboard sailboat 5 months ago and it came with a KID and a WBjr.  I'm in Mexico with brilliant sun all day long most days.  I might have several issues (or possibly none) but nothing is working the way I'm expecting it to.  I'm expecting to see batteries go to absorb / float every day and then drain each evening after the sun goes down.  That's what everyone else's systems do here.  Instead:

1.  In the 5 months I've been here I've seen the KID go to Absorb and Float (green LED) twice.  Once when I had to motor for about 2 hours and one other time.  The one other time coincides with the only time I've ever seen SOC read less than 100%. Voltage was down to 11.2ish.  I don't really know why it happened but I suspected it might be dust on my solar panels so I cleaned them and over the course of the next 3 days I watched SOC go up 20 or 30% each day until it hit 100% / Absorb / Float.  Green LED.  That was over a month ago.

2.  Since then, regardless what voltage my battery is reading (at the KID and w/ my multi-meter attached to the batteries), SOC reads 100%.  Doesn't matter if voltage is 12.5, 12.1, 13.0 or 13.7 - it always reads 100% SOC. 

3.  Even with a Newmar HDM 30 AC charger running, in addition to my 250W solar array, the battery never gets above about 13.8 volts and I never move out of Bulk mode, except those two times.  I've checked it as well it seems to be hooked up correctly and running normally - although it's not putting out more than 5 amps and I think it should be.  That might actually be a second problem.

I'm worried that the SOC reading is preventing the controller from working the way it should be.  I've read the KID manual, the WBJr Manual and many of these posts many times, checked every setting on every menu in the KID, (Even the advanced settings), opened the KID up to make sure everything looks like it's connected correctly (purple wire into the 'wbjr' marked port on the circuit board, etc), cycled the whole operation multiple times - and nothing seems wrong.  I even just replaced all my batteries 'cause they were getting old and I thought maybe they were just not holding a charge well.  (Yes - I reset all the parameters for the new batteries per the mfg specifications).   The instructions I found here for 'resetting the WBJr SOC reading' doesn't work for the KID as best I can tell 'cause I don't have the same options.  Any suggestions would be welcome.

boB

Hi Keith.  Welcome to our group here...

The WB Jr. software in the Kid and Classic (Classic may be the instructions you read ?), calculate SOC% based on amp-hours removed and amp-hours put back into the battery along with an inefficiency constant that is programmed into the charge controller.

The software for that calculation assumes that if your charge controller sits at the Absorb voltage for the programmed amount of time (2 hours typically),  and then goes to Float, that it is at 100% SOC.  This is usually a good sanity reset for the state of charge.

The 11.2V figure is considered dead and/or very discharged at that voltage.

But to get the battery to 100% SOC, the amp-hours in addition to that 90 something percent inefficiency should mean that the battery has been recharged.   You do need the periodic Absorb to make sure the battery does not sulfate and reduce its capacity.

Can you look to see how many amp-hours you have removed from the battery and it still says 100% ?  What is that capacity in A-H of the battery that is programmed into the Kid ?   If it was 200 A-H and you pulled out 50 A-H then it should show somewhere around 75% SOC as long as amp-hours were not put back into the battery and measured by the shunt connected to the WB Jr.

Also check the battery's electrolyte level IF it is not a no maintenance type of course.

Others will chime in here I'm sure to give even more advice.

boB
K7IQ 🌛  He/She/Me

ClassicCrazy

What kind of batteries do you have ?
Also what are your Absorb , Absorb time, and Float setpoints  set for ? Also temperature compensation setting ?
What is the battery capacity set up for in the Whizbang settings as well as the efficiency setting ?
The final thing to know is if the shunt on your system has only one wire going to the battery negative and every other battery negative is on the other side of the shunt ?

Larry
system 1
Classic 150 , 5s3p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system 2
 5s 135w Kyocero , 3s3p 270w Kyocera  to Classic 150 ,   8s Kyocera 225w to Hawkes Bay Jakiper 48v 15kwh LiFePO4 , Outback VFX 3648 inverter
system 3
KID / Brat portable

keith@keithayork.com

Thank you both  for the quick responses.  Answers to your questions.

1.  Yes, the AH reset instructions were for the classic.  Doesn't work the same way for the KID
2.  I don't see how to find amp-hours removed from the battery.  Is that a reading available on the KID?  All I see is voltage.  I purposefully watched everything very closely after the sun went down last night.  Turned off the AC charger so I knew nothing was going 'in'.  Turned on a bunch of stuff for a while to make sure I drew the voltage down.  It was at 13.4 at 7PM last night and at 12.2 this morning.  SOC still read 100% and Amp Hrs remaining says 489!!. (see capacity setting below).
3.  As mentioned - the batteries are brand new 3 days ago - Mexican brand LTH, which is Johnson Controls owned (good batteries), and rated at 232 each so I set the capacity at 464. Electrolyte levels are good.
4.  Absorb is set at 14.8 for 600 minutes (no idea why so long but the batteries never get to absorb so it's probably not material yet) and Float at 13.2.  Both per LTH specifications.
5.  Tcomp is set at -5.5mV
6.  Capacity for the WBJr is also wet at 464, efficiency at 85, temp at 25c and 1% per degree temp variance.
7.  There is one negative going from the battery bank to the shunt and one from the shunt to the controller.  Not exactly sure what 'every other battery negative is on the other side of the shunt' means

boB - I feel like the issue lies somewhere in that calculation you referenced.  If my KID can't see what amperage is going OUT then it never goes below 100. Thanks again for your help.  I'd be pulling my hair out if I had any.

Vic

#4
Hi Keith,

Out of curiosity,  is the green LED on the WbJr PCB,  flashing every 3 - 5 seconds?

With the solar panels (PVs) in bright sun,  with no shadows at all from shading,   what is the input voltage reading on the KID display?

What is the current rating and mV rating of the Shunt that the Wb uses,  if you can read it on the shunt?

250 Watts of PV is not really enough PV power for 464 Ah of battery (not knowing how frequently that external  charger runs).   If you are almost on shorepower,   then the smallish amount of PV power is not such a big deal.

Any shading can really kill PV production.  And,  boats often have shading on their PVs.

EDIT,  to add:   Your batteries sound like they are Flooded Lead Acid (FLA)  --  ones with easily-removeable top caps.   If so,  and you do not have one yet,  you will want a good quality Hydrometer (or Refractometer),  to measure the Specific Gravity (SG) of each battery's cells,  and record in your Battery Logbook.   Number battery,  letter each cell,  and record SG readings,  charge settings,   when distilled water was added,  and what amount,   when the bank was EQed, and what duration,  other observations, etc.

Often when placing a new FLA battery bank,  the manufacturer might suggest a full charge,   and then,  a Commissioning Equalize charge (an EQ).

All  IMO, Vic
Off Grid - Sys 1: 2ea SW+ 5548, Surrette 4KS25 1280 AH, 5.25 KW PV, Classic 150,WB, Beta Barcelona, Beta KID
Sys 2: SW+ 5548s, 4KS25s, 5.88 KW PV, 2 ea. Classic 150, WB, HB CC-needs remote Monitoring/Control, site=remote.
 MN Bkrs/Bxs/Combiners. Thanks MN for Great Products/Svc/Support&This Forum!!

keith@keithayork.com

Vic - the green light flashes every 5 to 6 seconds, just like it's supposed to.  I almost wish it didn't so I'd have something else to report.  I don't see ratings on the shunt but given the integrity with which everything else seems to have been setup I suspect it's the right one. 

Yes - I'm aware that my 250 watts of PV aren't enough long term.  And yes, they're flooded batteries and, although I don't have a hydrometer yet, I know I need to get one. 

At this point I'm trying to isolate issues and potential problem areas and solve them one at a time.  If my WBjr reported that my batteries were failing to get to 100% every day that would point me to bigger solar panels.  If running my AC charger every day, to supplement the solar, charged my batteries to absorb every day, I'd know that I'll need more panels, a generator, or to run the engine every day to keep my batteries full.  But the WBjr says my batteries are always, always, always at 100% SOC - even when they're reading 12.1 volts. 

Is it possible I just have a bad WBjr?   

keith@keithayork.com

A few more notes while I'm doing my research.  I checked and the firmware rev on my KID is 1860, definitely later than the 1811 referenced in the WBJr documentation.  I've also confirmed, if I didn't say this before, that the purple wire coming from the WBjr is going into the bottom port - labeled wbjr. 

One question I'll ask again since I didn't see a response yet - is there a way to see 'amp hours removed from the battery' with the KID?  I'm starting to think I just need something more robust than the KID to get all the info I want/need.  I'm a data junkie anyways.

Wizbandit

Where is the INVERTER connected?  Is the NEG of the Inverter connected to the SHUNT?  You can't just run the charge controller through the shunt and expect an accurate SOC.

keith@keithayork.com

Ok -I think I have this figured out.  Perhaps it's so basic you didn't even think to ask.  Again - I'm new to all of this.  When I bought my boat it was already all hooked up.  The negative going from the shunt to the battery is 'a' wire, not 'the' wire.  There are a dozen different negative leads going directly to my batteries.  Not kidding - a dozen. (See the photo - the wire I marked in Yellow is the wire back to the shunt.  Note: the adjacent battery, 2nd from the bottom, in the photo has as many negative leads directly into it as the first one does).  The more I read - the more I'm pretty sure not one of them is going "through" the shunt and therefore they're not being registered.  Does that sound right?   My guess is for as long as the PO had this boat the Whiz Bang Jr. never worked correctly.  Hmm - he forgot to mention that to me.

I think need a negative bus bar.   

boB


AhA !!   Looks like you have shown the problem in that yellow circled area maybe.

Everything will want to go through the shunt to the negative battery terminal.  Nothing but the shunt connected to the negative terminal.

A bus bar is a great idea.

As far as pulling hair out, mine has been gone for many years now too !   :D ;)

K7IQ 🌛  He/She/Me

ClassicCrazy

#10
If you have a few bucks and really want to improve that wiring here are my suggestions
Get a Midnite Mini DC box to clean up lots of that wiring mess.
https://www.solar-electric.com/midcdipocepl1.html
http://www.midnitesolar.com/productPhoto.php?product_ID=74&productCatName=Mini%20%20DC%20Disconnect&productCat_ID=8&sortOrder=3&act=p
You get the one with the breaker size that matches your inverter . The box has not only the main breaker but also room to put in 5 other dc breakers - one will be for DC input from PV the other DC output to battery. Then you would also have room for  three others to use for DC distribution to loads or another DC fuse panel. There is place to mount the shunt in there. It keeps all the wiring tidy and short using the supplied schematic
You can see that in the manual http://www.midnitesolar.com/pdfs/mndc125_250_manual.pdf
Also you may want to get a small hydraulic crimper or new cables new terminal ends for sure - some of the terminals on  your wires dont look too good .
Also the ones that are copper and not tinned copper corrode easier. The screw on terminal ends aren't that great to have.
https://www.harborfreight.com/hydraulic-wire-crimping-tool-66150.html
You can also find those crimpers on ebay.
You want to pay special attention to how the batteries are hooked up . See info in link below
http://www.smartgauge.co.uk/batt_con.html

Larry

Larry
system 1
Classic 150 , 5s3p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system 2
 5s 135w Kyocero , 3s3p 270w Kyocera  to Classic 150 ,   8s Kyocera 225w to Hawkes Bay Jakiper 48v 15kwh LiFePO4 , Outback VFX 3648 inverter
system 3
KID / Brat portable