Clipsal C-Bus Spezifikationen PDF herunterladen (Seite 48)

C-BUS TRAINING MANUAL - VOL 1

AC Output Impedance

C-Bus messages are voltage pulses which are superimposed over the d.c. power supply voltage. This

requires a high a.c. impedance to be present at communication frequencies. The power supply has a

special output stage that provides this impedance. General purpose off-the-shelf power supplies are

not suitable for C-Bus installations.

1.2 Network Bridge

A network bridge is a special linking unit that allows communication between two or more C-Bus

networks, while maintaining electrical isolation.

A C-Bus network bridge allows:

• relaying of messages between networks, allowing units on multiple networks to be programmed

and monitored from a central location

• transmission of commands which allow input units on one network to control output units on

another. Units across several networks can be assigned the same Group Address to provide this

high level of control.

A C-Bus network bridge has several limitations:

• the Multipoint to Multipoint Interrogation* (MMI) status report cannot be transferred across

a bridge. This means that an input unit controlling an output unit in another network, cannot

automatically correct itself

• a bridge can only send messages to its two adjacent networks plus one other. This limits inter-

network control when bridges are used in cascade form

• the maximum number of bridges that can be cascaded is six (in series). A star network topology

is recommended for most installations, and is required to interconnect more than seven

networks.

1 2 ... 43 44 45 46 47 48 49 50 51 52 53 ... 63 64

Keine Kommentare

Clipsal C-Bus Spezifikationen Seite 48