As major turbomachinery trains become more complex and critical, condition monitoring for maximum reliability becomes more important. Dedicated mini-computer systems appear to be the coming way to perform this task. This paper describes a typical mini-computer system hardware and its operations techniques with emphasis on its use for turbomachinery control in petroleum refineries. The ability of the mini-computer to reduce data and provide better operator presentation allows operators to make decisions based on a quick and complete picture of the situation. This advantage makes the mini-computer an attractive tool to be used by rotating machinery personnel to reduce downtime, improve efficiency and increase safety.