Z200 PV Analyzer
User Manual
NOTICE.
•
Due to the inherent uncertainty of the fault localiza-
tion method and due to the possibility of multiple
faults, it is highly recommended to verify a fault posi-
tion by bypassing a given faulty module or cable seg-
ment with a known good cable and verify string R
S
is
within range. Typically, a visual inspection of a sus-
pected faulty string element should clearly validate
fault position.
•
The accuracy of the fault localization is highly depen-
dent on the correct compensation of cable capaci-
tance. If cable lengths and capacitance per unit cable
length are unavailable, the user is advised to conduct
the measurement close to the string of PV modules,
thus omitting most of the cable between the instru-
ment and the solar module string.. This is the rea-
son for the two-step measurement process which al-
lows for a measurement from the positive terminal
to ground without the negative terminal being con-
nected and vice versa in terms of the measurement
from the negative terminal to ground.
•
Cable capacitance can also be measured by discon-
necting the cables from the string modules and run-
ning the ”Disconnect” test which will return the capac-
itance of both the cable segments. Use this informa-
tion to insert correct cable information. I.e. the prod-
uct of cable length and per unit length capacitance
should match the measured cable capacitances.
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