Error source signals can be combined to reduce the number of required inputs to a system controller when it is more important to know that an error has occurred than it is to know which device triggered the error. For example, if an overheating condition is detected, it is likely that the system will increase fan speed or shut down operations to respond to the issue regardless of which device signaled the error.

See more about this use case in the Logic Minute video Use Fewer Inputs to Monitor Error Signals.