7-Segment Display; Reset Button - Siemens SINUMERIK 840D sl Equipment Manual

3.4.3

7-segment display

Displaying messages
The 7-segment display is located behind the blanking plate of the NCU. It serves as a status
display during startup and performs the following tasks:
• Output of test and diagnostic messages.
• Output of status messages during booting
Critical messages
• During normal operation, "6" appears here and the dot flashes.
• An "8" indicates that the fan is defective or that the NCU is operating without a fan.
Additional references
Basic Software and Operating Software Commissioning Manual (IM7), Chapter "System startup
displays".
3.4.4

RESET button

Arrangement
The RESET button is located behind the blanking cover.
Performing a reset operation
The reset operation resets the NCU and forces a new power-up. It is similar to a "Power On Reset"
except that the 24 V power supply does not have to be switched off.
NCU 7x0.3B PN
Equipment Manual, 10/2020, 6FC5397-1EP40-6BA1
3.4 Operator control and display elements
Description
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