WTC-100 is a device to control the air velocity in a chamber-like wind tunnel or card rack. WTC-100 helps automate thermal characterization of heat sinks, boards, components in a wind tunnel or card rack testing for different fan tray configurations. It has two independent sensors for determining air temperature and velocity to facilitate rapid feedback of the airflow inside the test chamber. The controller communicates with a PC through an RS-232 port, enabling the user to fully automate air flow testing. Uni-sensor based control and measurement enables the user to control the air flow anywhere inside the test chamber. The flow range, step increment and the dwell time are set from the stageCONTROL Application Software by the user.