Description Of The Hardware; Description Of The Individual Modules; General Information On Central Units - Siemens Sirius 3RK3 System Manual

Description of the hardware

5.1

Description of the individual modules

5.1.1

General information on central units

Figure 5-1
Application
The application area for MSS central units is safety-related control functions. A central unit is
required for each system configuration. The central unit contains the configuring data in an
external memory module, and it handles all control tasks.
Power-up/self-test
Once the power supply has been applied, the system performs a self-test. During the self-
test phase, all the LEDs on the central unit light up for two seconds (lamp test). Two-color
LEDs light up yellow. The central unit then downloads the configuration from the external
memory module and checks whether the configuration/parameterization stored is valid.
The 3RK3 Basic switches to configuring mode (the DEVICE LED lights up yellow) when:
● No configuration exists
● The TARGET configuration differs from the ACTUAL configuration (the SF LED lights up
red)
● The modules could not be parameterized (the SF LED lights up red)
● The existing configuration has not been released.
If the memory module has not been installed or is defective, the 3RK3 Basic switches to
configuring mode. Diagnostics can currently only be carried out for the MSS (DEVICE LED
flashes red, SF LED lights up red).
Modular Safety System 3RK3
System Manual, 10/2008, 926 2530-02 DS 02
3RK3 Basic central unit
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