Switching To Insulated Operation; Switching To Grounded Operation; Insulation Monitoring With Remote Gfdi And Insulation Monitoring Device; Information On Insulating Pv Modules With Remote Gfdi And Insulation Monitoring Device - SMA SUNNY CENTRAL 500CP XT User Manual

SMA Solar Technology AG
The order option "GFDI and insulation monitoring device" allows you to manually switch the PV power plant from
grounded operation to insulated operation. To ensure that there is no insulation error on the grounded terminal, an
insulation measurement is carried out. After switching to insulated operation, the insulation monitoring device checks all
poles of the PV power plant for potential insulation errors. Switching to insulated operation is useful for performing
maintenance or service work on or near the PV power plant (e.g. cutting the grass) or for checking the status of the
insulation at regular intervals. After completion of the maintenance work, the PV power plant must be switched back to
grounded operation.
6.5.1.2

Switching to Insulated Operation

1. Turn the key switch to Stop.
2. Wait 15 minutes before opening the inverter. This will ensure that the capacitors are discharged.
3. Disconnect the circuit breaker of the GFDI manually.
4. Close the inverter.
5. Turn the key switch to Start.
☑ The insulation monitoring device starts collecting data. If the parameter IsoErrIgn is set to On, the error
3504 ‒ Insulation failure ignored is displayed.
✖ After 15 minutes, the displayed error 3504 does not disappear?
The insulation is defective.
• Have the insulation checked and, if necessary, repaired by a qualified person.
• Acknowledge the error.
6. Log into the user interface (see Section 9.4.1, page 78).
7. Wait a few minutes and then call up the instantaneous value Riso on the user interface.
☑ The insulation resistance is greater than 45 kΩ. It is safe to enter the PV system.
✖ The insulation resistance is less than 45 kΩ?
There is an insulation error and you must not enter the PV system.
• Have the insulation checked and, if necessary, repaired by a qualified person.
6.5.1.3

Switching to Grounded Operation

1. Turn the key switch to Stop.
2. Wait 15 minutes before opening the inverter. This will ensure that the capacitors are discharged.
3. Manually switch on the GFDI circuit breaker.
4. Close the inverter.
5. Turn the key switch to Start.
6.5.2 Insulation Monitoring with Remote GFDI and Insulation Monitoring Device
6.5.2.1 Information on Insulating PV Modules with Remote GFDI and Insulation
Monitoring Device
Ground-fault monitoring does not provide protection from personal injury. Ground-fault monitoring and the insulation
monitoring device enable the PV array to be switched automatically from grounded operation to insulated operation.
To ensure that there is no insulation error on the grounded terminal, an insulation measurement is carried out. After
switching to insulated operation, the insulation monitoring device checks all poles of the PV array for potential
insulation errors. Switching to insulated operation is useful for performing maintenance or service work near the PV
array (e.g. cutting the grass) or for checking the status of the insulation at regular intervals.
User Manual
6 Operation
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