Absorb voltage wrong?

[Volvo Farmer]

Don't know what I'm seeing here or what I'm doing wrong.

I had absorb and float to about 33V last week. Today, the turbine stars overspeeding and the clipper starts shutting down the turbine. I check Absorb and float, and they're back around 28.x volts.  Maybe because I reset the nominal system voltage from 12 to 24V last week?

So I set the voltages back up to 33 volts. I watch. The batteries get to about 29V and the controller goes out of bulk and into absorb. Batteries are within 10 degrees of 70F.  I don't want the controller in absorb at 29V. I recheck the  voltages, still at 33 and 32.9 respectively.

I'm pretty certain I pressed enter to save the settings to the memory but I went round and round the menu about 3 times and checked and adjusted voltages, and still it went into absorb at 29 volts.

I tried to start an EQ, to force bulk charging up to 33V, Still I saw the controller go out of EQ MPPT and into Equalize at some voltage less than 30V. Then I was unable to cancel the EQ. I went to EQgo! selected the off option, but it wouldn't take. So I shut the whole controller off for a while and that seemed to cancel the EQ cycle.

I lost the wind and the wife came home and started loading batteries after that, so I couldn't test further.

Do I need to disable MPPT mode to get the settings to stick? It did not seem to be working to change battery voltages today, even when I pressed enter to save the settings.

Thanks for the help

[Halfcrazy]

I suspect it is to do with the temperature compensation. Try unplugging the battery temp sensor. You can also go into the menu / charge / t comp / view and this will show you the target voltage the Classic is shooting for do to temperature compensation.

[Volvo Farmer]

Thank you. I will be out of town for a few days but will check on that and report back!

[boB]

Hey Volvo....

I know you may be talking with 1/2 Ryan about this already, but I bet I know what your problem is...

The MAX Temp Comp Voltage limit (in the CHARGER menu) is what is keeping your temp-comp'd
Absorb voltage from going high enough.  Change that MAX Temp Comp Voltage to something higher
than your Absorb Set point voltage.

This has already been addressed in the software but isn't released yet so you may have to do this
manually for the moment.

This information may want to go into either FAQ or the BUGs section actually.

boB

[Volvo Farmer]

Aha!

The Max Temp Comp voltage was indeed set at 29.2

I'm sure that will fix it but will have to wait for good wind and full batteries to fully test. I love having a fully configurable charge controller, I just need to figure out how to configure it!

[Halfcrazy]

Volvo
I am glad you found it and apologize for the inconvenience. Hopefully you are on your way to many happy KWH's produced