SolarEdge SE66.6KUS Installation Manual page 41

Connecting the Strings to the Connection Unit
Inverters may have a different number of pairs of DC input terminals, depending on the inverter power
rating. If more strings are required, they can be connected in parallel using an external combiner box
before connecting to the Connection Unit; strings connected to different units cannot be combined.
When connecting multiple strings, it is recommended to run separate circuits to the Connection Unit or
to position the combiner box near the Connection Unit.This simplifies commissioning by allowing testing
and servicing near the inverter.
To connect the strings to the Connection Unit with glands/Conduits:
1. Strip 5⁄16'' (8 mm) of the DC wire insulation.
2. Insert the DC conduit into the DC-side opening on the Connection Unit (left side a t the bottom of the
Connection Unit).
3. E quipment grounding: Connect the DC equipment ground conductor to the equipment grounding
terminal block (bus-bar) in the Connection Unit.
NOTE
Functional Electrical Earthing of DC-side negative or positive is prohibited because the inverter has no
transformer. Equipment grounding of exposed conductive surfaces in the array is required per the NEC.
4. Connect the DC wires to the DC+ and DC- terminal blocks, according to the labels on the terminals.
or; connect two wires (DC+ and DC-) per string:
a. Use a standard flat-blade screwdriver to connect the wires to the spring-clamp terminals. The
screwdriver blade should fit freely in the terminal opening. Too large a blade can crack the plastic
housing.
b. Insert the screwdriver and firmly tilt it to press the release mechanism and open the clamp.
c. Insert the wire into the top opening (see Figure 31).
d. Remove the screwdriver – the wire is automatically clamped.
CAUTION!
Ensure that the Plus (+) wire is connected to the + terminal and that the Minus (-) wire is connected to
the Minus (-) terminal connector.
Veillez à ce que le câble Plus (+) soit connecté au terminal + et que le câble - soit connecté au
connecteur terminal.
NOTE
For systems with four PV strings per unit or more, fuses may need to be installed in
both the positive and negative conductors as required by NEC Article 690.9. For more
information, refer to the Technical Note "String Fusing Requirements in SolarEdge
Systems" at http://www.solaredge.com/files/pdfs/string_fusing_requirements.pdf.
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-Three Phase Inverter with Synergy Technology Installation MAN-01-00402-1.4
Figure 31: DC Spring-clamp terminals