Classic 200 Display Reading "Resting"

[Montana Dave]

I use a Magnum Model MS4448PAE inverter and a Midnite 200 Classic charge controller for my 48-volt off grid system in western Montana.  Up until a couple of months ago, the readings on the charge controller display would track with the readings on the inverter display; bulk, absorb and float.  The battery voltage readings are always within a couple of tenths.  This time of year, we often run our backup generator in the morning to charge the batteries.  Now the charge controller reads resting most of the time.  I use the charge controller display to equalize the batteries once a month.  I cannot put the batteries into equalize while the display is reading resting.  Has anyone else seen this before?  If so, do you have a fix?

[ClassicCrazy]

My guess is that it is reading resting because the inverter is charging it higher than the setpoint of the Classic. There is a Reason for Resting code that you can look up.
I guess since you said you equalize that means you  have lead acid batteries ?
The temperature compensation settings will raise the charge voltage on Classic if the batteries are cold. Maybe on your magnum charger too ?
What is the battery voltage compared to the Absorb voltage when you see it in resting ?
I think it might be the battery voltage is higher than the Absorb voltage which would be reason for resting 38 if I remember correctly.
If that was the case and you put some loads on the battery to bring down the voltage then it should go out of Resting ?
Larry

[Montana Dave]

Larry,

Thank you for the reply.  I will comment and answer questions in the order you have written them.

Please take a look at the first attached photo and let me know if it addresses your first sentence.  The backup generator was running at this time.

I have looked up the Resting code in the Just the Facts guide for the Midnight Solar Classic.  I have confirmed the Code is not turned off.  I have checked the input voltage on the Solar Classic blue terminal block, and it matches the display.  See the second attached photo.  Backup generator was off, sunny day.

I do have lead acid batteries.  They are located in the basement of my off-grid cabin, cool in the basement but not cold.

My solar panels are now 13 years old, and the output voltage has dropped as they aged.  I am wondering if it has dropped so much as to cause the Resting reading.

I would appreciate any further thoughts you might have.  Thank you.

Dave

[ClassicCrazy]

I am a bit confused by your photos
The first one the inverter is charging ?
The second ones the solar is charging ?
What did you expect to see on the first photos ?
What are the charging setpoints you have in the Classic ?
Do you have any Vbat offsets set in the Classic ( in Tweaks section of mngp) ?
Do you have any voltage or current  limits set on the Classic ?
Larry

[Montana Dave]

Sorry for the confusion on the photos.  I was trying to show that the voltage reading on the Magnum and the voltage reading on the Midnite Classic are always tracking closely whether the generator is on, or the solar panels are charging the system.  I think this shows that there is sufficient voltage on the input to the Classic.  This came from the Troubleshooting guide in the Classic Just the Facts document.

I have a 48-volt system.  The charging setpoints on the Classic are Bulk MPPT = 58.0, Float = 55.6, Equalize = 60.8. These are slightly different from the values in the Just the Facts document and were recommended by the company I purchased the system from.

All other settings: Vbat offsets, voltage or current limits would be the factory settings.

Dave

[Montana Dave]

Larry,

An update.  I spoke with technical support at MidNite Solar and now think the error is mine.  The original flooded lead acid batteries lasted from 2013 to 2021.  I replaced the original Deka batteries with new Deka batteries but did not update the bulk, absorb and equalization voltages and times.  I have now done that in the MidNite Solar charge controller and Magnum Energy inverter.  The readings on the two displays are starting to track each other like I was used to seeing.  The MidNite Solar technical support person said it may take a while to get the batteries back in line.  Thank you again for your help.

Dave

[FNG]

In picture 1 the Classics input voltage is to low to do anything with, assuming its snow covered, night or such.

In general IF the classic has sufficient PV available AND the battery voltage is below the Classics target it will charge even if the Magnum is charging too, when usually happens as he Absorb cycle starts one or the other device will manage the Absorb by itself as one of the devices sees the battery as full just do to calibration