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Place the I-V Unit near the PV circuits to be measured .................................................................................... 4-3
Connect the test leads to the PVA ..................................................................................................................... 4-3
Launch the PVA software ................................................................................................................................. 4-3
Load your Project .............................................................................................................................................. 4-3
Insert the wireless USB adapter (PVA-1000S and PVA-600+) ........................................................................ 4-3
Mount SolSensor ............................................................................................................................................... 4-4
Attach SolSensor thermocouple ........................................................................................................................ 4-4
Turn on the I-V Measurement Unit, and connect wirelessly to your PC .......................................................... 4-4
Turn on SolSensor ............................................................................................................................................ 4-5
Prepare the PV source circuits for measurement .............................................................................................. 4-5
Are you measuring strings in parallel?.............................................................................................................. 4-5
Are you measuring high-efficiency modules? .................................................................................................. 4-5
Connect the test leads to the PV equipment ...................................................................................................... 4-6
Select the first PV circuit to be measured ......................................................................................................... 4-6
Make your first measurement ........................................................................................................................... 4-6
Select the next PV circuit and take another measurement ................................................................................ 4-7
View the consistency of your data before moving on ....................................................................................... 4-7
From time to time, back up your data ............................................................................................................... 4-8
5 TROUBLESHOOTING PVA OPERATION ................................................................................................... 5-1
TROUBLESHOOTING USING STATUS MESSAGES ..................................................................................................... 5-1
TROUBLESHOOTING BY SYMPTOM ......................................................................................................................... 5-4
6 MEASURING IRRADIANCE, TEMPERATURE, AND TILT ..................................................................... 6-1
INTRODUCTION ...................................................................................................................................................... 6-1
MEASURING IRRADIANCE WITH SOLSENSOR ......................................................................................................... 6-3
SolSensor irradiance sensor .............................................................................................................................. 6-3
Preliminary Irradiance ...................................................................................................................................... 6-3
SolSensor Precautions ....................................................................................................................................... 6-3
Protecting the Irradiance Sensor Element ..................................................................................................... 6-3
Cleaning the Irradiance Sensor ..................................................................................................................... 6-3
Orienting and mounting the irradiance sensor .................................................................................................. 6-4
Albedo effects ................................................................................................................................................... 6-4
Diffuse light ...................................................................................................................................................... 6-4
DETERMINING IRRADIANCE FROM THE MEASURED I-V CURVE ............................................................................. 6-5
ENTERING IRRADIANCE MANUALLY ...................................................................................................................... 6-6
MEASURING PV MODULE BACKSIDE TEMPERATURE WITH A THERMOCOUPLE ..................................................... 6-6
Selecting a thermocouple wire gauge ............................................................................................................... 6-7
Selecting a thermocouple tip ............................................................................................................................. 6-7
Selecting a tape for thermocouple attachment .................................................................................................. 6-7
Attaching the thermocouple to the module backside ........................................................................................ 6-8
Choosing a location to mount the thermocouple on the module or array.......................................................... 6-8
MEASURING PV MODULE TEMPERATURE WITH AN INFRARED THERMOMETER ....................................................... 6-9
DETERMINING CELL TEMPERATURE FROM THE MEASURED I-V CURVE .............................................................. 6-10
USING SMARTTEMP TO MEASURE CELL TEMPERATURE ...................................................................................... 6-11
7 INTERPRETING MEASURED I-V CURVES ................................................................................................ 7-1
INTRODUCTION ...................................................................................................................................................... 7-1
INPUTS TO THE PV MODEL ..................................................................................................................................... 7-1