Solmetric PVA-1000S, User Manual

Page: 64 / 152

1 Getting Started
2-52
I-V Measurements
The I-V Measurement Unit will measure an I-V curve each time you click on the
Measure Now button. I-V data is transmitted to the PC shortly after each I-V sweep is
taken. Data is not stored in the I-V Measurement Unit after it is transmitted. The Voc
measurement is performed the instant before the actual I-V sweep begins.
Sweep Disabled
PV current is stopped automatically at the end of each I-V measurement. However,
before connecting or disconnecting test leads or cables, press the LED pushbutton on the
front of the I-V Measurement Unit to disable the measurement sequence. Manually
disabling the I-V Measurement Unit in this way will assure that an I-V measurement is
not accidentally taken when it is not expected. When you’re ready to take another
measurement, just press the LED pushbutton again.
WARNING If the LED on the PVA is illuminated (either solid on or flashing), do not connect or
disconnect the PV leads.
Over-Temperature Protection
Built-in safeguards prevent the I-V Measurement Unit from operating at potentially
damaging internal temperatures.
The I-V Measurement Unit absorbs energy with each measurement, and across a series of
measurements the instrument's internal temperature gradually increases. Some of this
accumulated heat is shed during the time between measurements and while the equipment
is being moved around the site between measurement sessions. If, on average, the heat
gain exceeds the heat loss and the internal temperature continues to rise, the internal
temperature sensor is triggered. When that happens, the I-V Measurement Unit shuts
down to allow the instrument to cool down, and the PVA software posts the
Disabled
message in the Status indicator, directly above the Measure Now button.