Troubleshooting steps
medium
SINUMERIK 840D
40020 – HMI communication fault
HMI communication error
Details
alarm
Error typeHMI communication
MeaningCommunication cable fault HMI fault
Typical causesCheck HMI communication cable verify HMI status restart
Solutionsmedium
Catalog references
System Information
SINUMERIK 840D40020
Utilities
Troubleshooting Steps
Other alarms
Other SINUMERIK 840D Alarms
22050 – Channel not ready
NC channel failed to initialize or is in error state
25000 – Emergency stop active
Emergency stop button pressed or safety circuit activated
25050 – Axis hardware fault
Axis drive or motor detected a hardware fault condition
30000 – Drive alarm
Drive system detected an alarm condition
30010 – Drive communication fault
Drive communication error with control
FAQ
Common questions
Can I continue?
Limited operation possible but HMI functions unavailable
Community
Discussion & Experiences
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