ABB AC 31 - 2. CS 31 bus technical specifications

Technical specifications
ABB Control - AC 31 Page 3-5
1SBC 260400 R1001-b 06.99
2. CS 31 bus technical specifications
Type
RS 485 multipoint serial interface
Mode
Half-duplex
Number of connection points
1 single master
max. 31 slaves
Support
- Section
- Twists
- Resistance
- Impedance specification
- Capacity
- Shielding
- Line termination
Shielded twisted pair
0.22...0.8 mm²
> 10 per meter
≤ 100 Ω / km
100 à 150 Ω
< 150 nF / km
Braiding
Resistance 120 Ω, ¼ Watt, connected
to each extremity of the bus
Protocol
ABB CS 31 (master/slave)
or MODBUS slave
Transmission control
CRC
Maximum length
up to 500 m without amplifier
up to 2000 m with 3 amplifiers
(NCB or NCBR)
Bus redundancy
yes with NCBR
Isolation
yes by optocoupler
Refresh time
2 ms minimum
typically 12 ms with 31 CS 31 interfaces
Speed
187.5 kBauds