MI 3109 EurotestPV Lite
Measurements
44
Figure 5.29: Examples of PV measurement results
Displayed results are:
MEAS column
U.............. measured output voltage of the panel
I ............... measured output current of the panel
P .............. measured output power of the panel
STC column
U.............. calculated output voltage of the panel at STC
I ............... calculated output current of the panel at STC
P .............. calculated output power of the panel at STC
Pstc… ...... measured output power of the panel at STC
Pmax…... nominal output power of the panel at STC
η1….. ....... efficiency of the panel at STC
Pmeas… . measured output power of the panel at momentary conditions
Ptheo…. .. calculated theoretical output power of the panel at momentary
conditions
η2…...... calculated efficiency of the panel at momentary conditions (simplified
method, see appendix E)
U:............. actual voltage on test inputs
Notes
:
Before starting the PV measurements settings of PV module type and PV test
parameters should be checked.
For calculation of STC results PV module type, PV test parameters, Uoc, Isc, Irr
and Tcell values must be measured or be entered manually before the test. The
results in ENV. and Uoc/Isc menus are considered. If there are no results in
Uo/Isc menu the instrument will consider results in I-V menu.
The Uoc, Isc, Irr and T measurements should be carried out immediately before
the PANEL test. Environmental conditions must be stable during the tests.
For best results the A 1378 PV Remote Unit should be used.
5.5 Measuring of environmental parameters
Temperature and solar irradiance values must be known for:
calculation of nominal values at standard test conditions (STC),
checking that environmental conditions are suitable for carrying out the PV tests.
The parameters can be measured or entered manually. The probes can be connected
to the instrument or to the PV remote unit A 1378.
