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000954AG
8 - Maintenance
M
easuring the isolation resistance of the PV generator.
The operator must always use the personal protective equipment (PPE) required by the laws
of the country of destination and whatever is provided by their employer.
To measure the isolation resistance of the PV generator compared to
ground , the two poles of the PV generator must be short-circuited
(using a suitable sized switch).
Use of unappropriate sized switch could cause risk of fire or electric arc! Use only 1500V
rated switch!
+
_
IG
Once the short-circuit has been made, measure the isolation resistance
(Riso) using a megohmmeter positioned between the two shorted poles
and ground (of the inverter).
Mega
Inverter
IG
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If the measured isolation resistance (Riso) is less than 33 kOhm, the
inverter may not connect to the grid because of low isolation of the PV
generator to ground.
The isolation resistance can be affected by the environmental conditions the PV generator is
in (E.g.: PV modules wet from damp or rain), and therefore the measurement must be made
immediately after the anomaly is detected
