18
Figure 6 Circular topology
Figure 7 Cable break between transmitter 2 and 3. Communication has broken down into 2 independent BUSes. No
communication was lost.
4.5.1
Cabling installation for RS485
The cabling must be suitably dimensioned to prevent excessive voltage drops on the bus. It is recommended that for 32
transmitters on the bus/ring, the maximum distance between the control panel and the last transmitter is 500 m. For 16
transmitters, this length is then doubled.
In the Czech Republic, the control panel is approved for use only with Prakab PraFlaGuard 2x2x0.8 cables. In other countries,
any cables of a similar type can be used.