SolarEdge SE3000H-US Installation Manual page 32

To connect the strings to the DC Safety Unit:
1. E quipment grounding: Connect the DC equipment ground conductor to the equipment grounding
terminal block in the DC Safety 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.
2. Insert the DC conduit into the DC-side opening on the DC Safety Unit (left side a t the bottom of the
DC Safety Unit).
3. Connect the DC wires to the DC+ and DC- terminal blocks, according to the labels on the terminals,
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.
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.
ATTENTION!
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.
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.
5. Close the DC Safety Unit cover: Attach the switch cover and secure it by tightening the four screws
with a torque of 1.2 0 .9 ft.*lb.
6. Ensure proper conduit sealing; inspect the entire conduit run and use standard conduit sealants to
avoid water penetration.
Single Phase Inverter with HD-Wave Technology Installation MAN-01-00306-1.1
Chapter 4: Connecting the AC and the Strings to the Safety Switch
31