Temperature Differences Between Classics

[finalman]

As the topic says I'm wondering what kind of temperature difference one could expect between classics mounted right next to each other. I ask this as I've noticed one of my classics runs hotter than the other.

My situation is I have two classics in follow me mode:

#1 - Classic 150 with BTS and WBjr and shunt
#2 - Classic 150-SL

Solar Arrays

#1 - 1.2kw north (12v panels 6 in series)- connected to #1 classic
#2 - a single 200w 12v E to W rotatable panel - connected to #2 classic

So the situation is my #1 classics FETs and PCB runs about 7 degrees Celsius hotter than #2 classic. The thing is though I took those degrees with both classics in float mode with #1 classic only producing a few watts and #2 classic producing like 60 watts. I've also not heard #2 classics fan yet but I hear #1 classics all the time during bulk, absorb and during floating on hot days as well.

Would the different classic models explain this at all?

Would the PV array input voltages into the classic cause this?

Or could this be a mosfet heat transfer issue?

If not what else would cause something like this?

[BobWhite]

I'm confused!

I see two systems that aren't the same yet the question is why they don't act the same
I must be missing something here im sure! can you give more information on the systems ?

Walt

[finalman]

I'm confused!

I see two systems that aren't the same yet the question is why they don't act the same
I must be missing something here im sure! can you give more information on the systems ?

Walt

Basically when floating classic #1 runs hotter than classic #2 but also inputs less watts into the battery than classic #2.

Just had a thought. I'll switch the arrays connected to the Classics tonight and see if the temperatures reflect the changes tomorrow.

[Westbranch]

Use your Local App and check every setting as well.  you may have an offset or ??  that is set differently on the 2 Classics which is causing as well as all connections.... it only takes one under torqued connection to create a problem... 

[Halfcrazy]

Well array #1 is "Bigger" and "Higher Voltage" so yes both of those, Especially the voltage will cause more heat

[zoneblue]

And once the controllers are out of bulk , they will never share exactly evenly, even if the arrays were identical.

In short, no worries at all there..