6 Electrical Connection
3. Release the screws of the DC protective cover
using an Allen key (AF 3) and remove the DC
protective cover.
4.
Damage to the inverter due to moisture and dust intrusion
Electronic components in the inverter can be destroyed or damaged as a result of dust or
moisture intrusion. The enclosure openings are suitable for conduits of 25.4 mm (1 in).
• Only use one opening per string.
• Do not enlarge the enclosure openings.
5. Remove the adhesive tape from both openings.
6. Insert one conduit fitting for each string into the opening and tighten from the inside using the
counter nut.
7. Attach one conduit for each string to the opening.
8. Insert the DC cables through the conduit into the interior of the inverter.
9. Strip the insulation of the DC cables by 18 mm (0.71 in).
10. For connecting the string to INPUT A, connect the DC cables to the connecting terminal plate
for the DC connection:
• Connect the positive DC cable to the red terminal A+ and tighten with a screwdriver
(torque: 5.8 Nm (51 in-lb)).
• Connect the negative DC cable to the black terminal A- and tighten with a screwdriver
(torque: 5.8 Nm (51 in-lb)).
11. For connecting the string to INPUT B, connect the DC cables to the connecting terminal plate
for the DC connection:
• Connect the positive DC cable to the red terminal B+ and tighten with a screwdriver
(torque: 5.8 Nm (51 in-lb)).
• Connect the negative DC cable to the black terminal B- and tighten with a screwdriver
(torque: 5.8 Nm (51 in-lb)).
12. Ensure that all DC cables are securely in place.
13. Close unused enclosure openings with UL-listed type 3R filler plugs.
14. If required, you must connect additional grounding or equipotential bonding (see
Section 6.3.3, page 29).
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STPTL-US-10-IA-xx-17
SMA Solar Technology America LLC
Installation Manual