Chapter 4: Connecting the AC and the Strings to the Inverter
Chapter 4: Connecting the AC and the Strings to the Inverter
Refer to Technical Specifications on page 55 for inverter specifications .
Connecting the AC Grid to the Inverter
The AC output gland can fit an AC cable external gauge of PG21 (9-16mm diameter) .
The maximum wire size for the input terminal blocks is 16mm².
For more wiring information refer to the SolarEdge Recommended AC Wiring Application
Note, available on the SolarEdge website at http://www.solaredge.com/files/pdfs/application-note-recommended-wiring.pdf.
1. Turn OFF the AC circuit breaker.
2. Open the inverter cover: Release the six Allen screws and carefully move the cover horizontally before lowering it.
CAUTION!
When removing the cover, make sure not to damage internal components. SolarEdge will not be held responsible for any components damaged as a result of incautious cover removal.
3. Strip 58 mm / 2.32'' of the external cable insulation and strip 8 mm / 0.32'' of the internal wire insulation.
Figure 7: Insulation stripping – AC (3-wire cable)
4. Open the AC cable gland and insert the cable through the gland (see Figure 3).
WARNING!
Turn OFF the AC before connecting the AC terminals. If connecting equipment grounding wire, connect it before connecting the AC Line and Neutral wires.
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SolarEdge HD-Wave Inverter Installation Guide MAN-01-00250-1.1
Chapter 4: Connecting the AC and the Strings to the Inverter
5. Insert the AC cable through the supplied Ferrite bead.
6. Connect the AC wires according to the labels on the terminal block.
Figure 8: AC connection
7. Tighten the screws of each terminal with a torque of 1.2-1.5 N*m / 0.88-1.1 lb*ft.
8. Check that the wires are fully inserted and cannot be pulled out easily.
9. Tighten the AC cable gland with a torque of 2.8-3.3 N*m / 2.0-2.4 lb*ft.
10. Verify that there are no unconnected wires to the inverter and that the unused terminal screws are tightened.
Connecting the Strings to the Inverter
Connect the string to the DC input pairs. If required, connect additional strings in parallel using an external combiner box/branch cables before connecting to the inverter.
NOTE
Functional electrical earthing of DC-side negative or positive poles is prohibited because the inverter has no transformer. Grounding (earth ground) of module frames and mounting equipment of the PV array modules is acceptable.
NOTE
SolarEdge’s fixed input voltage architecture enables the parallel strings to be of different lengths.
Therefore, they do not need to have the same number of power optimizers, as long as the length of each string is within the permitted range.
Connect the DC connectors of each string to the DC+ and DC- connectors according to the labels on the inverter.
Figure 9: Inverter DC Connections
SolarEdge HD-Wave Inverter Installation Guide MAN-01-00250-1.1
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Selecting a Residual Current Device (RCD)
Selecting a Residual Current Device (RCD)
IMPORTANT SAFETY FEATURE
All SolarEdge inverters incorporate a certified internal Residual Current Device (RCD) in order to protect against possible electrocution and fire hazard in case of a malfunction in the PV array, cables or inverter. There are 2 trip thresholds for the RCD as required for certification
(DIN VDE 0126-1-1). The default value for electrocution protection is 30 mA, and for slow rising current is 300 mA.
If an external RCD is required by local regulations, check which type of RCD is required for the relevant electric code. SolarEdge recommends using a type-A RCD. The recommended RCD value is 100mA or
300mA unless a lower value is required by the specific local electric codes. When required by local regulations, the use of an RCD type B is permitted.
NOTE
For multiple inverters, an RCD per inverter is required.
In installations where the local electric code requires an RCD with a lower leakage setting, the discharge current might result in nuisance tripping of the external RCD. The following steps are recommended to avoid nuisance tripping of the external RCD:
l
Select the appropriate RCD for correct operation of the installation: An RCD with a rating of 30mA may actually trip at a leakage as low as 15mA (according to IEC 61008). High quality RCDs will typically trip at a value closer to their rating.
l
Configure the trip voltage of the inverter' internal RCD to a lower value than the trip current of the external RCD. The internal RCD will trip if the current is higher than the allowed current, but because the internal inverter RCD automatically resets when the residual currents are low it saves the manual reset.
For detailed information, refer to the RCD Selection for SolarEdge Inverters Application
Note, available on the SolarEdge website at http://www.solaredge.com/files/pdfs/seapplication-rcd-selection.pdf
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SolarEdge HD-Wave Inverter Installation Guide MAN-01-00250-1.1
