Embodiments of the present disclosure generally provide apparatus and methods for monitoring one or more process parameters, such as temperature of substrate support, at various locations. One embodiment of the present disclosure provides a sensor column for measuring one or more parameters in a processing chamber. The sensor column includes a tip for contacting a chamber component being measured, a protective tube having an inner volume extending from a first end and second end, wherein the tip is attached to the first end of the protective tube and seals the protective tube at the first end, and a sensor disposed near the tip. The inner volume of the protective tube houses connectors of the sensor, and the tip is positioned in the processing chamber through an opening of the processing chamber during operation.