Connecting The Strings To The Safety Switch - SolarEdge UL1741-SA Installation Manual

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Connecting the Strings to the Safety Switch

Connecting the Strings to the Safety Switch
You can connect systems with multiple DC strings in parallel to the DC input terminals
of the Safety Switch. 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
Safety Switch. When connecting multiple strings, it is recommended to run separate
circuits to the Safety Switch or to position the combiner box near the Safety Switch.
This simplifies commissioning by allowing testing and servicing near the inverter.
NOTE
Use 16-6 AWG, 75-90°C copper wires only.
To connect the strings to the Safety Switch:
1. Equipment grounding: Connect the DC equipment ground conductor to the
equipment grounding terminal block in the Safety Switch.
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 Safety Switch (left side at the
bottom of the Safety Switch).
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.
Single Phase Inverter with HD-Wave Technology Installation MAN-01-00541-1.4