Westermo TD-36 User Manual
Page 14
14
6618-2202
* Railway installation close to the rails.
For a cable located within 3 m and connected to this port, the use of shielded cable is recommended, this is
to minimise the risk of interference. The cable shield should be properly connected (360°) to an earthing point
within 1 m of this port. This earthing point should have a low impedance connection to the conductive enclo-
sure of the apparatus cabinet, or similar, where the unit is built-in. This conductive enclosure should be con-
nected to the earthing system of an installation and may be directly connected to the protective earth.
RS-422/485
Electrical specification
EIA/TIA-485 ITU V.11
2-wire or 4-wire twisted pair
Data rate
300 bit/s – 115.2 kbit/s
Data format
7 or 8 data bits, Odd, even or none parity, 1 or 2 stop bits.
9-12 bit words
Protocol
Transparent
Retiming
Yes
Turn around time
<10 µs (half duplex)
Transmission range
≤ 1200 m, depending on data rate and cable type (EIA RS-485)
Settings
120 W termination and failsafe biasing 680 W
Protection
Installation Fault Tolerant (up to ±60 V)
Isolation to
Power port
3 kV
rms
50 Hz 1 min
PSTN Line
2 kV
rms
50 Hz 1 min
Leased Line
2 kV
rms
50 Hz 1 min
I/O
1.5 kV
rms
50 Hz 1 min
Galvanic connection to
RS-232
Connection
Detachable screw terminal
Connector size
0.2 – 2.5 mm
2
(AWG 24 – 12)
Shielded cable
Not required*
Miscellaneous
Do not connect RS-232 and RS-422/485 simultaneously
RS-232
Electrical specification
EIA/TIA-232
Data rate
300 bit/s – 115.2 kbit/s
Data format
7 or 8 data bits, Odd, even or none parity, 1 or 2 stop bits.
9-12 bit words
Protocol
Transparent
Retiming
Yes
Transmission range
Cable length ≤ 15 m
Isolation to
Power port
3 kV
rms
50 Hz 1 min
PSTN Line
2 kV
rms
50 Hz 1 min
Leased Line
2 kV
rms
50 Hz 1 min
I/O
1.5 kV
rms
50 Hz 1 min
Galvanic connection to
RS-485
Connection
9-pin D-sub female (DCE)
and Detachable screw terminal (DCE )
Connector size
Detachable screw terminal 0.2 – 2.5 mm
2
(AWG 24 – 12)
Shielded cable
Not required*
Miscellaneous
Do not connect RS-232 and RS-422/485 simultaneously