Solmetric PVA-1000S, Руководство пользователя

Страница: 102 / 152

4 Making Measurements
4-2
Make sure you have all your equipment
Personal Protective Equipment
I-V Measurement Unit in its soft case, with a complete set of Solmetric-provided gear in
its gear pouch. The pouch should contain PVA test leads, wireless USB adapter (not
needed for PVA-1500xx), PVA software on a flash drive, and PV connector tools.
SolSensor in its soft case, with a complete set of Solmetric-provided gear in its gear
pouch. The pouch should contain, a special bar clamp for mounting SolSensor on the side
of a PV module frame, thermocouples for measuring PV module backside temperature,
discs of green high-temperature tape for attaching the tip of the thermocouple to the
module backside, purified water and cleaning cloth for cleaning the irradiance sensor, and
a special tool lanyard to secure SolSensor to the racking.
Assure adequate irradiance for your measurements
Performance measurements are best performed in the range of 700-1000 watts per square
meter. If possible, choose a day when the skies will be clear. If there are clouds, try to
trigger your measurements at moments when there are no clouds near the sun. Also try to
do your measurements in a 6-hour window centered on solar noon.
If you are measuring a horizontal single-axis tracker, you can set up the Project to allow
the tracker to keep running as you do your measurements. This provides a more
consistently high irradiance during the day.
Making Measurements in the Field
Measure the open circuit voltage Voc
If the open circuit voltage Voc of the PV source circuit exceeds the I-V Measurement
Unit's maximum DC input voltage specification, your instrument may be damaged.
Before starting your measurements at a new PV field, make sure Voc is within the
instrument's DC voltage range by measuring a string with a properly rated Digital
Multimeter. This simple step can prevent damage to your instrument and save you a lot of
time.