"override control" refers to a system in process control where an automatic control loop temporarily overrides another automatic control loop when certain process parameters go beyond a setpoint.
This allows the process to be quickly and automatically corrected in the event of unexpected changes or deviations from normal operating conditions. The override control is designed to take over when the normal control system is no longer able to keep the process parameters within their set range, ensuring that the process remains stable and safe. Once the conditions have returned to normal, the normal control system resumes operation and the override control is deactivated.
In this context, override control serves as a safety mechanism to prevent process upset and maintain process stability. It is a critical component in ensuring safe and efficient operation of complex process systems.