Siemens SIMATIC S7-1200 Manual page 278

Technical specifications
A.8 Communication interfaces
Technical data
Isolation
RS485 signal to chassis ground
RS485 signal to CPU logic common
Cable length, shielded
Baud rate
Parity
Number of stop bits
Flow control
Wait time
Table A- 61 Power supply
Technical data
Power loss (dissipation)
Current consumption (SM Bus), max.
Current consumption (24 VDC) max.
CB 1241 RS485 (6ES7 241-1CH30-1XB0)
①
devices on the RS485 network.)
②
278
Connect "TA" and TB" as shown to terminate the network. (Terminate only the end
Use shielded twisted pair cable and connect the cable shield to ground.
CB 1241 RS485
500 VAC, 1 minute
1000 m max.
300 baud, 600 baud, 1.2 kbits, 2.4 kbits, 4.8 kbits, 9.6 kbits (default),
19.2 kbits, 38.4 kbits, 57.6 kbits, 76.8 kbits, 115.2 kbits,
No parity (default), even, odd, Mark (parity bit always set to 1),
Space (parity bit always set to 0)
1 (default), 2
Not supported
0 to 65535 ms
CB 1241 RS485
1.5 W
50 mA
80 mA
Easy Book
Manual, 11/2011, A5E02486774-04