11
SOCOMEC - Réf. : 874 669 A GB
Modem RS232 <=> RTC <=> RS485
SPECIFICATIONS
Interface specifications
RS485
Electrical specification
EIA / TIA-485 ITU V.11
2-wire or 4-wire twisted pair
Data rate
1 200 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 us (half duplex)
Transmission range
≤
1 200 m, depending on data rate and cable type (EIA RS485)
Settings
120
Ω
termination and failsafe biasing 680
Ω
Protection
Installation Fault Tolerant (up to ±60 V)
Isolation to
Power port
3 kVrms 50 Hz 1 min
PSTN line
2 kVrms 50 Hz 1 min
Leased Line
2 kVrms 50 Hz 1 min
I / O
1.5 kVrms 50 Hz 1 min
Galvanic connection to
RS232
Connection
Detachable screw terminal
Connector size
0.2 - 2.5 mm
2
(AWG 24 - 12)
Shielded cable
Not required
(1)
Miscellaneous
Do not connect RS232 and RS485 simultaneously
(1) 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 enclosure of the apparatus cabinet, or similar, where the unit is built-in. This
conductive enclosure should be connected to the earthing system of an installation and may be directly connected to the protective earth.
