REC TwinPeak 2 - 285w Panels Installed - Are they Performing?

[Matrix]

So I finished my modest first solar install a week ago to day. Spent the last week wrapping my head around the systems performance (not truly there yet), but also enduring some cloudy / rainy weather. Today is the first day of no clouds, full sun since install.

So now I am wondering if the Panels are putting out as expected. To me the numbers are low, but maybe its the time of year. Maybe its just me again not understanding solar.

Set up:
- REC TwinPeak 2 285w Poly panels in a 3S 3P array 2,610 watts (see the MidNite Solar Est attached)
- Time of day. Solar Noon for my location. 1:15pm EST
- No Clouds / full sun / 76* / 65% humidity
- Angle of Panels 16* / Facing Due South
- Off Grid system with batteries / SW Conext 4024 inverter / MidNite Solar Classic 150 CC / All wiring correct or over sized

Conditions:
- Charging batteries in EQ at 32v / 59 amps from the CC
- Running everything else on the system for a load.
- Total Load ... 2600 watts continuous

The most I could see the Array producing was 1900 watts. Less than expected. MidNite Solar Classic Calc for the array says to anticipate 2457 watts

Is this system inefficiency?
Still not enough load? (I added a tread mill and on or off it still would not rise above 1900 watts being produced
Do I have a bad Panel?
"You don't yet understand solar, Lad" ... This is just the way it is? Nothing to see here ... keep moving.
Or something else?

[sensij]

1900 / 2610 = 73%. That doesn't sound bad. I have a grid tie 18.5 deg, south facing array in San Diego that peaked at 70.6% yesterday, although we have Santa Ana's coming through and the heat hurts.

Have you modeled your system in PVWatts yet? It doesn't apply perfectly to a battery system, but it can be a decent indicator of the upper limit of production you might see at various times of year.

[Matrix]

PV Watts? I have not ... is that an app or a web site?

Oh and BTW ... the temp today here in full sun was 76* with 65% humidity.

[sensij]

PV Watts? I have not ... is that an app or a web site?

Oh and BTW ... the temp today here in full sun was 76* with 65% humidity.

Here:

http://pvwatts.nrel.gov/

Read the help screens. Probably 10% loss is better than 14%, at least for estimating DC production potential of the array. Don't trust the AC numbers, since the losses between charge controller/battery/inverter are not represented. Hourly output option gives more granularity so you can see modeled power at solar noon, but you should read up on what a TMY weather file is and understand how it is used before you get too far into it.

[NEOH]

Is current in EQ mode limited to 60 amps?
I don't know.

Maybe, you need to try this in Bulk Mode
The Amps in Bulk Mode should not be limited to 60 amps on Classic 150

What was the "Vmp" and "Imp" at the Input when this is occurring
Was input Volts low?
Was input Amps low?

What was the temperature of the cell inside the panel?
Hot = lower volts.

Is the 285 Watts rating an STC rating or an NOCT rating?.

STC ..... 9 x 285 watts = 2,565 Watts
NOCT .. 9 x 214 watts = 1,926 Watts

In another thread we were told to use STC ratings,
but so many times in the real world, actual output is more like NOCT.

[Matrix]

Is current in EQ mode limited to 60 amps? No. that is just what it did for that Charge

What was the "Vmp" and "Imp" at the Input when this is occurring
Was input Volts low?
Was input Amps low?

Don't know for sure ... but I know the VOC of each Series String with No load is between 96-103 volts for each string

Is the 285 Watts rating an STC rating or an NOCT rating?.

The Rating is for the STC ... and you are correct ... the NOCT is 214 ... so that would mean I am getting exactly what the adjusted numbers would be.

STC ..... 9 x 285 watts = 2,565 Watts
NOCT .. 9 x 214 watts = 1,926 Watts

In another thread we told to use STC ratings,
but so many times in the real world, actual output is more like NOCT.

I am truly seeing NOCT as an output right now. (Or I guess ... LoL)

[J.P.M.]

PV Watts? I have not ... is that an app or a web site?

Oh and BTW ... the temp today here in full sun was 76* with 65% humidity.

Expect the air temp. on your roof to be ~ 2C.- 4C. warmer than the reported ground ambient air temp., and your array's temp. to be ~ 25C. - 30C. above that under full sun, depending on solar incidence angle. Humidity doesn't matter much when it comes to array temps.

[J.P.M.]

PV Watts? I have not ... is that an app or a web site?

Oh and BTW ... the temp today here in full sun was 76* with 65% humidity.

As Sensij suggested for PVWatts.

As for temps. and suggestions, see my recent post. Also, when you want to get serious and really understand what you're asking and want basic information beyond just answers to questions, read Duffie & Beckman as I suggested in a prior thread.

[Matrix]

Thanks All. Looking into some of these suggestions now