3 Using the PVA-600
3-6
1.
Isolate the PV module string to be tested (test string) from the inverter and from
other strings in the array. If the measurement is being made at a fused DC combiner
box, isolate the combiner box by means of a DC disconnect switch, and isolate the
PV strings from one another by pulling their fuses.
2.
Press the button on the I-V Measurement Unit to disable the I-V sweep.
WARNING
PV circuits continue to present danger of electrical shock while system is paused.
FAILURE TO TAKE APPROPRIATE SAFETY PRECAUTIONS COULD LEAD
TO PERSONAL INJURY OR LOSS OF LIFE.
3.
Following safe operating procedures, connect the insulated test leads of the PVA-600
to the test string. The connection may be made at PV connectors at the ends of the
test string, or by clipping to the de-energized buss bars in a DC combiner box as
shown in Figure 8, using suitable test leads with MC-4 connectors at one end and
insulated alligator clips at the other end.
Figure 8. Example of PVA-600 test leads clipped to the buss bars of a PV combiner
box
4.
If one or both of the terminals of the test device must be some distance from the I-V
Measurement Unit, use extension cables made of UL (or equivalent) listed PV wire,
with correctly installed connectors. Select a wire gauge that will introduce minimal
voltage drop.
5.
When extension cables are longer than 10 feet (one-way), lay the cables close to one
another to minimize added cable inductance.
6.
If connecting at a fused combiner box, insert the fuse for the string to be measured.
