Siemens Cerberus GW-21, Техническое руководство, Страница: 5 / 44

1
Siemens Building Technologies
Cerberus Division
E1481b
06.2000
1 Introduction
The GW-21 Gateway provides the following main functions:
1. interface between subsystems and operator workstations (LMS or a foreign system);
2. interactions among subsystems:
3. protocol conversions.
The GW-21 gateway is composed by one CPU board with serial communication capa-
bility to which can be connected an optional expansion board with additional serial lines
in a piggyback configuration.
In a two level network architecture, the GW-21 can be used as communication layer
that connect the subsystems to a higher level GW-20.
The GW-21 complies with the latest European Union standards for emission and im-
munity to electromagnetic disturbances. It is designed to replace the GW-01.
i
GW-21 rev. B has a new connection board and galvanic isolation on power supply for
CS11 compatibility.
Old GW21 rev. A is still available in appendix D.
Two kinds of hardware configurations are foreseen:
GW-21.06
This configuration has 6 serial lines; it requires CPU board and an additional expansion
board with two more asynchronous serial lines. Using this configuration you can con-
nect up to four subsystems to one or two workstations.
GW-21.04
This configuration has 4 serial lines; it is composed by the CPU board that has on-
board 4 communication lines. Up to three control panels can be connected to one
workstation, or it can connect two workstations and two subsystems.