Why is my Classic 150 holding back charging current?

[qrper]

We had a winter storm knock us around for a few days. Batteries were down to 77%, I normally drop them off the system when they hit 20% discharge, so this time a bit deeper at 23%.
So to day we got a bright, not a cloud in the sky, day, and according to both the status panel on my computer and the display on the Classic I'm seeing 74.3 A going into the batteries.

Now, my question is, I have plenty of PV, about 6Kw and I have the Classic set at 83 A max, why aren't I seeing the Classic max out on current on a day like this?

I'm in bulk charge. 57.7 V battery, 74.2 A charging current, and 4297 W being produced. The batteries are in the cold garage, at 9.2ºC

Even though the battery bank certainly isn't' discharged more than 23%, I figured with all the PV pushing current into the Classic,  I'd see the Classic hit the fence at 83A and sit there until the battery become more charged.

Ideas anyone?

[Vic]

Hi Mike,

Seems to me,   that your PVs are doing fine.

Even in your fairly Southern location,   the track of the sun across the sky,  is lower than in the Summer.  This will reduce the peak solar output.

Haze and water vapor in the atmosphere will reduce solar production,   then there is the elevation angle of the PVs,  which can mean that there is less production,   unless the PVs track,  or you change this setting,  seasonally.

As you also know,   when one looks at the WbJr battery charge current,   vs CC output current,  this will reduce the apparent output.

This 6 KW system,  may be grid-tied,   so,   it is not clear what your other loads might be affecting Wb charge current,  vs CC total output,   etc.

Just a drive-by Post.   73  GL,   be safe,    Vic    . .

[Vic]

Will add several things to the previous,

Generally use an easy fudge-factor when estimating the approximate maximum,   real world PV module output at the solar maximum on a clear,   sunny day   --  75% of the rated STC PV output.   Cold/windy days can allow more than this nominal estimate.

Some use NOCT ratings  for the exact PVs being used.   Some PV data sheets to not have the NOCT Power,   Vmp,  Imp, Voc, etc data listed.

Then there is the really useful tool,   from the US NREL (National Renewable Energy Labs)  --  the PVWatts Calculator:
https://pvwatts.nrel.gov/index.php

IMO,  your PVs are doing fine,   but,   there are SO many variables involved.

FWIW,   73  GL,  Vic

[boB]

For sanity sake,  take note of the MPPT PV intput voltage versus the Voc Open Circuit PV voltage.

MPPT V should normally be somewhere around 80% of the Voc.   If it is too much higher or lower than that, it may be a tracking issue.

You can't get more power out than the Vmp allows at that voltage.  The Vmp might be +/- a few percent from 80% but fairly close.

You can also check for proper tracking voltage by pressing the upper left (soft left) and upper right (soft right) keys while in the main status menu to raise and lower the PV input voltage and see if you can get much more output power at a slight different input voltage.

[qrper]

Will add several things to the previous,

Generally use an easy fudge-factor when estimating the approximate maximum,   real world PV module output at the solar maximum on a clear,   sunny day   --  75% of the rated STC PV output.   Cold/windy days can allow more than this nominal estimate.

Some use NOCT ratings  for the exact PVs being used.   Some PV data sheets to not have the NOCT Power,   Vmp,  Imp, Voc, etc data listed.

Then there is the really useful tool,   from the US NREL (National Renewable Energy Labs)  --  the PVWatts Calculator:
https://pvwatts.nrel.gov/index.php

IMO,  your PVs are doing fine,   but,   there are SO many variables involved.

FWIW,   73  GL,  Vic

Thanks of the note Vic

I know the panels only do full power under a very tight set of rules. That being said, it was rather cold, about 20º F and bright. I had 890 wmsq during the day.
The classic acted like it hit a fence, never did I see the current exceed 73.4 A.
I'm sure everything is fine, but I'm the kind of guy that sees things differently.

73
mike

[qrper]

For sanity sake,  take note of the MPPT PV intput voltage versus the Voc Open Circuit PV voltage.

MPPT V should normally be somewhere around 80% of the Voc.   If it is too much higher or lower than that, it may be a tracking issue.

You can't get more power out than the Vmp allows at that voltage.  The Vmp might be +/- a few percent from 80% but fairly close.

You can also check for proper tracking voltage by pressing the upper left (soft left) and upper right (soft right) keys while in the main status menu to raise and lower the PV input voltage and see if you can get much more output power at a slight different input voltage.

Bob,

I didn't write the values down but I recall the PV voltage at 83 V and current 53 A coming in. The system is 48 V nominal

[boB]

Yes, the input voltage won't do any good unless you know the Voc as well.

Next time you think of it, you can look at both maybe.