E2
Severe error
ABB · AC500 CPUs
What does E2 mean?
This severe error signifies that while the operating system itself is functioning, the error-free processing of the user program cannot be guaranteed. A common cause is a checksum error detected in the user Flash memory, which impacts program execution stability. Unresolved, this can lead to incorrect program logic, unexpected machine behavior, or intermittent operational failures without crashing the entire OS.
Source: ABB AC500 CPUs
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