Endress+Hauser WirelessHART Fieldgate SWG70 - Connecting to RS-485

Electrical Installation WirelessHART Fieldgate SWG70
26 Endress + Hauser
Internal wiring The Ethernet socket is wired to the Ethernet terminal block. The internal wiring may not be
modified.
5.4 Connecting to RS-485
Fieldgate SWG70 is equipped with a fully galvanic isolated RS-485 interface. A second
RS-485 terminal block allows several Fieldgates to be connected through a daisy chain.
A terminating resistor is required at each end of the RS-485 cable. If the RS-485 cable is not
routed to other devices (no daisy-chain connection), activate the terminating resistor using
the corresponding DIP switches in the fieldgate. See Chapter 6.1.3 "DIP switches" on page 31.
NOTICE!
• The maximum length of the cable from the Fieldgate is 1200m (at reduced
communication speed).
• Use shielded twisted pair (STP) cables only.
• If the cable shield is grounded, only connect the grounding to one cable end. This avoids
potential equalization currents.
• Ensure adequate strain relief for the cables.
• Pay attention to the bending radii of the cables. Do not drop below the permitted bending
radii.
Fig. 5-5: RS-485 interface
Pin Numbering Connector Signal Internal Wire Colors
Pin 1 TX+ Yellow
Pin 2 RX+ White
Pin 3 TX– Orange
Pin 4 RX– Blue
3
4
2
1
1 First RS-485 connection 2 Second RS-485 connection for daisy chaining
KL1 KL2 KL3 KL4
+24V +24V
0V 0V
LINE1 LINE2
A
B
SHD
RS485
T1
T2
RX–
RX+
TX–
TX+
ON
OFF
SHD
A
B
SHD
RS485
ETHERNET
KL5 KL6
A
B
SHD
RS485
A
B
SHD
RS485
1
2