SMA America, LLC
Multicluster Operation
Technical Description
SI5048U-TUS121440
139
Each Multicluster Piggy-Back (MC-PB) is delivered with one yellow and one gray RJ45 communication
cable and two plugs (termination resistors).
You require the yellow cable to establish communication between the master of the main cluster and
the masters of the extension clusters.
The gray cable is used for external communication (via RS485) needed for the system monitoring
(Sunny WebBox).
Proceed as follows when connecting the communication cable:
1. Remove the left of the two plugs from the cable insert.
2. Feed the RJ45 cable from the outside through the plugs inside the Sunny Island master.
3. Plug the RJ45 plug in the lower socket. The termination resistor remains plugged in the upper
one.
4. Lead the RJ45 cable into the next Sunny Island and connect it to the upper socket there.
5. Insert the termination resistor into the lower socket if no other Sunny Island will be connected.
6. Wrap the rubber plug (with one or two entries, depending on the number of cables) around the
RJ45 cable.
7. Reinsert the plug in the opening provided in the cable insert.
RJ45 Cable
The RJ45 communication cable is a standard Cat5e-FTP cable (simple shielding), with gold
contacts.
Multicluster Piggy-Back
If just one cluster is used in connection with an MC-BOX, no Multicluster Piggy-Back is
required.
