Measuring The Isolation Resistance Of The Pv Generator - ABB PVS-100 Product Manual

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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.
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
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 suitably sized selector).
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).
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.
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8 - Maintenance
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