Specifications

Third-Party and Building Management Interfaces
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5.3.2 Port A—RS-232 to RS-485 Modbus
If the third-party device communicates using RS-232 point-to-point, but the configuration requires
multiple SiteLinks, use a REPOPT to convert RS-232 to RS-485. The RS-232 can be either DB-9 or
two-wire screw terminal connection types.
Figure 13 Modbus on Port A—RS-232 to RS-485
5.3.3 Port B—RS-232 Modbus
Use Port B for communications between one SiteLink and the other vendor, where the vendor’s equip-
ment is up to 50 ft. (15m) away. This is a DB-9 connection using the RS-232 protocol. If the vendor’s
equipment also uses a DB-9 connection, the connection is three wire, ASYNC, continuous connection.
Figure 14 Modbus on Port B—RS-232
Figure 15 Modbus on Port A—RS-232
Table 15 Bill of materials: Port A—RS-232 to RS-485 Modbus
Qty. Mktg. P/N Description
2 SITELINK-4-M SiteLink-4-M (4 Liebert IGM interfaces)
1 REPOPT EIA-485 signal to EIA-232 signal converter
2 XFMR24 Transformers for 120/24VAC module power supply
Note: The bill of materials does not include LGS startup part numbers. Most LGS startup part
numbers are added automatically when ordering.
Table 16 Bill of materials: Port B—RS-232 Modbus
Qty. Mktg. P/N Description
1 SITELINK-4-M SiteLink-4-M (4 Liebert IGM interfaces)
1 XFMR24 Transformers for 120/24VAC module power supply
Note: The bill of materials does not include LGS startup part numbers. Most LGS startup part
numbers are added automatically when ordering.
Third
Party
Network
RS-485
Daisy Chain
RS-232
Point-to-Point
REPOPT
Third
Party
Network
RS-232
Point-to-Point
Third
Party
Network
RS-232
Point-to-Point