Comparison of Open Loop and Closed Loop Control Systems

Feature Open Loop Control System Closed Loop Control System
Effect of Output on Input No effect on input The input signal affects the controller output into the system
Stability Very Stable The response changes as the input signal changes.
Response to external disturbances No reaction to disturbances.  The Open Loop control works on fixed output The output of the controller adjusts itself in response to the input signal
Ease of Construction The controller is easy to construct Controller is difficult to construct as it is complex
Cost Cheap Expensive
Bandwidth Small Bandwidth Large Bandwidth
Maintenance Low Maintenance More Maintenance is required. 
Feedback There is no Feedback Feedback is always present.