JUMO 705001 mTRON T - Central Processing Unit Operating Manual - Manual (Page 38)

5 Operation
38
5.4 LED displays
"Power" LED
If the central processing unit is being supplied with voltage, the LED is lit permanently in green.
"Status" LED
This LED indicates the system state and – in combination with the "BusError" LED – errors in
the system. Possible displays are listed in the "System states and errors" section.
 Chapter 5.4.2 "System states and errors", page 40
"BusError" LED
This LED indicates problems relating to the system bus and the modules that are connected to
the central processing unit.
In combination with the "Status" LED, it also indicates errors in the system. Possible displays
are listed in the "System states and errors" section. Diagnostics requires the setup program or
a Web browser.
"Com1" and "Com2" LEDs
These LEDs indicate the status of the relevant interface. The display depends on the system
version.
Version 01:
•
LED off: Interface module is not equipped
• LED flashes green and red: Error (defective interface, wrong setting. or wrong connection)
• LED flashes green: Communication is active
Version 02:
•
LED off: Interface module is not equipped
• LED is lit green: Interface module is equipped, no communication
• LED flashes green: Communication is active
• LED flashes red: Communication error
- for Modbus master: Slave does not answer.
- for Modbus slave: Timeout detected (master does not answer).
- for PROFIBUS (Com2): External communication to the master is disrupted.
• LED is lit red, only for PROFIBUS (Com2): Internal error
For diagnostics in the event of an error, the setup program or a web browser is required.