Need help with battery temperature compensation

[Jacotenente]

Hey guys...I am little stuck on what value I should enter for my battery bank specs in the MNGP temperature compensation offsets:

Battery temps (in the garage, 24v system) - between 35-50F
12 Trojan L16E-AC batteries - 36 cells total
Trojan specs say .0028 volt per cell for every 1 deg F below 77F.

I have the MNGP temp offset set for -5 mv/0C/cell with a temperature window of 25C.

Is this correct? Thank you for your help...not 100%. I did call tech support...but, wanna be more certain.

Chris

[Vic]

Hi Chris,

YES,  -- 2.8 mV/F  IS  -- 5 mV/C.   And C is what the Classic uses,  so that is correct.

Trojan uses a Reference Temperature of 80 F,  so,  this is close to 27  C.   Believe that temperature Window,  is the same as the Reference temperature.

Do not have a Classic right at the fingertips,  at this moment.

FWIW,   Vic

[Jacotenente]

Hi Chris,

YES,  -- 2.8 mV/F  IS  -- 5 mV/C.   And C is what the Classic uses,  so that is correct.

Trojan uses a Reference Temperature of 80 F,  so,  this is close to 27  C.   Believe that temperature Window,  is the same as the Reference temperature.

Do not have a Classic right at the fingertips,  at this moment.

FWIW,   Vic

Vic - I think I was hit by a "stupid stick"...it happens as age creeps up.
1) 5 mv/C is exactly what the Temperature Compensation should be set at (all the time)
2) Trojan L16E-AC specs even specify it
3) With the Midnite Solar battery temperature sensor hooked up...the Classics should adjust accordingly as the ambient temperatures go up/down (or am I wrong?)

Thanks

Chris (I am not an engineer, but I really dig this stuff!)

[Vic]

Hello Chris,

The Classic ONLY needs the compensation factor of -- 5mV to be entered,  and 27 C.

You may be accustomed to the Schneider "programming",   where the user needs to know the number of cells in the battery and do the multiplication of number of cells X  the comp factor.

The Classic is much smarter than Schneider,  or their programmers,  and does the math for you!

The Reference temperature is 27 C.  SO,  you only need to enter -- 5 mV,  and 27 C,  and you should be good to go.

Schneider seems to want to save a penny here and a tenth of a penny there,  so they do not do any calculation,  to speak of,  in the CC,  and force the user to do it for them,   and they save a cent or so per unit ...   seems stupid to me ...

Make sense?   Vic

[Jacotenente]

Hello Chris,

The Classic ONLY needs the compensation factor of -- 5mV to be entered,  and 27 C.

You may be accustomed to the Schneider "programming",   where the user needs to know the number of cells in the battery and do the multiplication of number of cells X  the comp factor.

The Classic is much smarter than Schneider,  or their programmers,  and does the math for you!

The Reference temperature is 27 C.  SO,  you only need to enter -- 5 mV,  and 27 C,  and you should be good to go.

Schneider seems to want to save a penny here and a tenth of a penny there,  so they do not do any calculation,  to speak of,  in the CC,  and force the user to do it for them,   and they save a cent or so per unit ...   seems stupid to me ...

Make sense?   Vic

Yep...100% agree. Data entered, thanks Vic!

Chris

[mike90045]

Hello Chris,

The Classic ONLY needs the compensation factor of -- 5mV to be entered,  and 27 C.

You may be accustomed to the Schneider "programming",   where the user needs to know the number of cells in the battery and do the multiplication of number of cells X  the comp factor.

The Classic is much smarter than Schneider,  or their programmers,  and does the math for you!.....

Which is all fine, until you try to use a battery other than lead-acid with different cells per 12V block.  Then Schneider wins for flexibility.