Level control loops are widespread and necessary in the industry to monitor and control the process properly, and to ensure the safety and efficiency of the plant. If the level of the substance is not properly measured or maintained correctly, it can result in production loss, the damage to the equipment and process. Therefore, control loops will always carry out the following three actions in order to avoid undesirable situations: measurement, comparison, and modification. In order to maintain the stability of the system and perform the mentioned tasks, level control loop technologies of BHOS test rig are selected according to the system requirements. This system comprises the needed components for automated control: the sensing device, the disturbance source, the controller, and the final control element (FCE). Firstly, the level transmitter measures tank level and sends a signal to the related level controller. Guided-Wave-Radar level/interface transmitter is selected as it has a long measuring range and less sensitivity to the disturbances. Then, the controller compares measured value with the desired value and transmits a control action to FCE. The best-suited algorithm for controlling the system is Proportional-Integral - PI control. If required, the controller can be tuned using Trial-and-Error approach. Lastly, the valve receives a control action and opens to allow some liquid to exit the tank. The globe valve is selected as it is most suitable for full-range flow control situations. In addition, the inlet pump speed can be altered and disturbance to the system can be created by altering the frequency of the Variable-Frequency-Drive. As a result of technology review and design of the loop for the test rig, technical documentation used at various phases of the project will be created for the system. As a contribution to the future curriculum, lab work instructions will also be prepared based on the project.