KEPCO BOP 1KW as Solar Device Tester Quick Start Guide User Manual

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KEPCO, INC. " 131-38 SANFORD AVENUE " FLUSHING, NY. 11355 U.S.A. " TEL (718) 461-7000 " FAX (718) 767-1102

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determines the resolution or level of detail of the charac-
terization and can be set to as few as 10 to as many as
40,000 points per I-V Curve. Clicking the Swap Voltage
Sign or Swap Current Sign buttons to the left of the I-V
curve allows rendering of the I-V curve as preferred for I-V
Trace and I-V Dark type tests.

Clicking the Press to Take Sample button causes the
application to invoke the subvi which changes the BOP
output, creating a linear ramp. At each step, the BOP
1KW provides a measured voltage and current value.
While the curve is being taken, the voltage and current
values (displayed under BOP Parameters) change, pro-
viding status to the user. When the ramp is completed,
these measurements are provided as an array, which the
application renders as the I-V curve shown in Figure 1.
The subvi also provides measured Vmp and Imp, which is
graphically marked on the curve with a cursor formed by
intersecting vertical and horizontal lines.

SOLAR DEVICE TESTER SUBVI. The Solar Device

Tester subvi, written in LabView, includes an operator
panel (see Figure 2). The subvi may be used as is in an
overall Test application. The overall application will typi-
cally use the measurement data provided by the Solar
Device Tester subvi to produce an I-V curve that charac-
terizes the device, and includes the four key device char-
acteristics: Voltage Maximum Power (Vmp), Current
Maximum Power (Imp), Voltage Open Collector (Voc) and
Current Short Circuit (Isc) as well as Maximum Power
Point (Pmp). The calculated values of Vmp, Imp and Pmp
appear under Real Time Output. Isc and Voc are the high-
est values that appear in the Measured Current and Mea-
sured Voltage Arrays, respectively. Figure 1 shows a
typical I-V curve characterizing a solar device produced
from the data accumulated by the Solar Device Tester
subvi.