SMA Sunny Data Control V.4.2 - Manual (Page 24)

Connecting the PC to a Communication Device SMA Technologie AG
Page 24 SDC-TEN080642 User Manual
5.2. 2 Connection via RS485
RS485 communication characteristics:
• Up to 50 Sunny Boy Control / Plus devices can be connected to a PC.
• The PC must be equipped with an RS485 port. If it is not, please read section 5.
1 „Notes on the Use of Level Converters” (page 20).
• Each Sunny Boy Control requires an RS485 Piggy-Back at the PC (COM 2) port.
Alternatively, at the Sunny Boy Control Plus, the AUX (COM 3) port can be used,
if this is equipped with an RS232 Piggy-Back.
• The maximum total cable length is 1200 m
Cabling Recommendations
The cable length and quality have an effect on the signal quality. To achieve a good
quality signal, observe the following instructions regarding cabling:
•
Use metallic D-Sub female connectors. Connectors made of plastic, or metallized
plastic, can cause faulty data transfer.
• For the outdoors, use a communications cable with the following important
qualities:
- Cross-section: at least 2 x 2 x 0,22 mm
2
, and at least 2 x 2 x AWG 24
- shielded
- Twisted Pair
- UV-resistant
We recommend the following cable types for outdoors:
SMA communications cable: COMCAB-OUTxxx*
*available in the following lengths xxx = 100 m/200 m/500 m und 1000 m.
Lappkabel: UNITRONIC Li2YCYv 2 x 2 x 0,22 mm
2
For the outdoors you can also use a data cable designed for indoor use, if you
protect it against UV radiation with an appropriate cable duct.
RS485