FLOAT and SOC

[Ray Strickland]

I have a battery bank with 225 AH ( eight Trojan T-105's) in series 48 volts.
I have Absorption Charge set at 59.2  Float Charge 52.8 and Equalize Charge 62.0 per Trojan Specs.

I am using classic 200 controller and MAGNUM energy MS 4448 PAE with MMP175-30D panel.
My solar panels are 3 Solarworld SW 335 MONO. (1005 watts total)

My question is the controller goes to float and 100% SOC with 12 ah left before I reach battery capacity of 225 ah,
can this be corrected to where I reach battery capacity of 225 ah when battery is at 100% soc.
It appears to me I am unable to use 12 ah of my battery bank.

Thank you

[Vic]

Hi Ray,

It is possible that your batteries are not at the Reference Temperature,  which is usually 80 F (about 27 C).

If your battery temperature is a bit below this Reference temp,  then their Capacity will be diminished by the temperature measured by the Classic's Battery Temperature Sensor (BTS),  AND the battery Capacity factor verses temperature that you set when you configured your Classic.

Believe that the Default Capacity factor is 1%/C,   IIRC.

FWIW,   Vic

[Ray Strickland]

The temperature in my battery box is 71 F degrees right now.
I don't understand the T-Com setting. I have it set now at  -.5mv.
The REMOTE readings are 37.0 & Battery 19.9
The FETS 45.0 PCB 49.8 are they a part of this setting.
I have read the manual many times but can not grasp  what it means.
Have enclosed trojans temp chart.
HELP
Thanks

[Vic]

Hi again Ray,

The Classic reads your battery temperature as about 20 C.   Full Capacity would be available if the battery bank is at about 27 C,  nominal  (believe that Trojan uses 80 F/ 27C as the Reference temperature.

If you have set the Capacity vs temperature factor as 1%  or,  left this  factor at the Default,  this available Capacity readout is nominally correct,  IMO.

Also,  IMO,  none of the Capacity numbers are absolutely accurate  --  neither the numbers from the battery manufacturer,  nor  estimates from any Batter Monitoring device,  they are just approximate,  or nominal numbers.

The accuracy of any battery monitoring device depends upon the parameters that the user sets,  the approximations of Capacity from the manufacturer,  the Rate that the battery is discharged,  the Rate that the battery is charged,  and a number of other factors that the average user cannot know,  or appreciate just how these factors change over the life of a battery bank.

These are just my opinions  --  battery monitoring devices are a terrific rough estimate of the present state of the battery bank,  and are best used as a rough guide,  not as absolutes.

FWIW,    Vic

[Vic]

The temperature in my battery box is 71 F degrees right now.
I don't understand the T-Com setting. I have it set now at  -.5mv.
The REMOTE readings are 37.0 & Battery 19.9
The FETS 45.0 PCB 49.8 are they a part of this setting.
I have read the manual many times but can not grasp  what it means.
Have enclosed trojans temp chart.
HELP
Thanks

OK,  Ray,

A bit more of a reply ...

The battery charge Temperature Compensation is in the Charge menu,  and tells the Classic weather and how much Temp Compensation of the charge voltage is required.  This compensation is only for the charger functions  --  Absorb,  Float and perhaps the EQ VOLTAGES (if you have set the EQ voltage to be temp compensated).

The Capacity verses Temperature setting is different,  and is in the WbJr Setup menu.  The Default of this setting is 1% of rated Capacity for every 1 degree C change in measured battery temperature.   This means that if your battery temperature is measured at about 19.9 C,  and you have set the battery Reference temperature at 27 C,  then the Classic with the WBjr installed,  will reduce the available Capacity by about 7%

If you have not set either the Reference Temperature,  or the Capacity change verses temperature in the WbJr Setup menu,  then the Classic will use the Defaults of 25 C,  and 1% Capacity change for each degree C change from 25 degrees C.  So in this case,  the temperature change is -5 C,  so the Capacity would be REDUCED by about 5%,  which is about what you are seeing on the display of available battery Capacity.

Vic

[Ray Strickland]

Thanks
That helped a lot, I feel I have a better understanding.

[Ray Strickland]

If I add another string of 8 Trojans in parallel does it have to be the same current value of 225 AH (T-105) or can I increase with Trojans T-125 which has 240 AH's. I know the voltage is the same in parallel but does the the current have to be the same also.?
Would this help me on the % of capacity I used and go to float better.
Thank you
Ray

[Cniemand]

You'll need to have the same aH capacity in the additional set of parallel batteries otherwise one side or the other will murder the other. If you have 240aH cells and 225aH cells eother the 225aH are going to be over charged or the 240aH cells are going to always remain undercharged. When the 225aH cells hit their top voltage the other 240aH cells with not be fully charged. 

You only want to add batteries that are the same.

[Vic]

If I add another string of 8 Trojans in parallel does it have to be the same current value of 225 AH (T-105) or can I increase with Trojans T-125 which has 240 AH's. I know the voltage is the same in parallel but does the the current have to be the same also.?
Would this help me on the % of capacity I used and go to float better.
Thank you
Ray

Hi Ray,

Yes,  parallel strings of batteries should be the same AH Capacity,  technology,  brand and fairly close in age,  and even very similar temperatures.

For parallel strings,  one wants to have each string sharing charge and discharge currents as equally as possible.   Having parallel strings of differing Capacities can lead to imbalances in the current in each string.   The string with the lowest impedance  will generally hog much of the charge current,  leaving the other string/s  undercharged.

Vic

[Ray Strickland]

That is what I needed to know.
Thank you very much.

[ClassicCrazy]

Some other things to consider when setting up your battery capacity and the SOC is what efficiency setting you put in for the battery . I think the default is 94% ?  You may want to lower it , or lower your battery capacity. This would be because it is better to have extra capacity left than to run it down too low - or even get yourself used to using less.

The other thing is that the SOC will go to 100% as soon as it changes from Absorb to Float. So  you need to make sure  your batteries are really getting full - either by adjusting the Absorb time or by setting up Ending Amps.  I think you said you have flooded lead acid so that way you could test the electrolyte with a hydrometer to makes sure that when it is saying 100% they actually are fully charged.  Same thing if you use ending amps to stop Absorb .

Larry

[Ray Strickland]

I purchased 8 more Trojans T-105. I added water to correct level and charged each battery. I then added them to my battery bank. I set classic with the new battery's info and all was working fine and monitoring them for a couple of months with the local status panel on my PC until today.
The classic is still sending info to the local status Panel but whizbang jr has stopped. On the classic panel whizband jr shows --NO-WB-- but appears to still show some data but no SOC info data.
I don't under stand, as I have web access or the classic would not send data to the Local Status Panel right?
Do you have any ideas as to what may be going on. 

[Vic]

Ray,

There is a green LED on the WBjr circuit board that flashes about every five seconds,  when things are working well.   Can you see this LED flashing?  About how often is the if flashing?

You should probably turn off the Classic's PV input breaker,  then turn off the Classic's battery breaker,  and wait for 30 seconds or one minute,  and turn the battery breaker on followed by switching the PV in breaker back on.

If this did not do anything for you,  then you should check that Aux 2  is set for WBjr input/output.

Is it possible that the addition of the additional battery string somehow disturbed the Purple wire from the WB?

Also check all of the wiring on the Shunt,  including how well torqued are the large cables and the torque on the screws that mount the WBjr to the Shunt.

While you are at it,  do check that the purple wire is seated correctly into the Aux 2 contact inside the Classic.

Please let us know how you are doing,   Thanks,   Vic

[Ray Strickland]

First every thing has been working good for about 2 months after adding the batteries.
The green light on whizbang jr is working correctly.
I turned off breakers and reset, with no change.
I went into classic and reset up whizbang jr and it is now showing good data instead of --NO-WB-- on classic.
Still not able to set Local Status Panel to see whizbang jr, it does not appear as a selection on aux 2 as it did before.
It may be because I am using a different computer now that the one I was using died. I am building a new computer and using my son's  temporary . It looks like the norton protection software may be blocking some info. Is this possible because it does connect to my LAN and can view the classic.
Also while resetting up whizbang I got into an area that has set to SMA and I can not get it back because it keeps asking for a password. I can find nothing in the manual to help me get out of this mess with the password. I do not know what the password is or how to get back to the way it was.....HELP....Thanks

[Resthome]

First every thing has been working good for about 2 months after adding the batteries.
The green light on whizbang jr is working correctly.
I turned off breakers and reset, with no change.
I went into classic and reset up whizbang jr and it is now showing good data instead of --NO-WB-- on classic.
Still not able to set Local Status Panel to see whizbang jr, it does not appear as a selection on aux 2 as it did before.
It may be because I am using a different computer now that the one I was using died. I am building a new computer and using my son's  temporary . It looks like the norton protection software may be blocking some info. Is this possible because it does connect to my LAN and can view the classic.
Also while resetting up whizbang I got into an area that has set to SMA and I can not get it back because it keeps asking for a password. I can find nothing in the manual to help me get out of this mess with the password. I do not know what the password is or how to get back to the way it was.....HELP....Thanks

Yes Norton can block some Midnite files. You need to go into Norton and restore any Midnite files that are being blocked.

The PW is the Serial Number of your Classic.