Sensor system for detecting contaminant in fluid

A sensor system for sensing contaminants within a fluid stream, the sensor system comprising:

• a sensor body and an arm extending from the sensor body to a distal end of the arm, wherein the arm is insertable into the fluid stream;
• a light source disposed in the sensor body and configured to direct a light beam outwardly from an outlet of the sensor body towards the distal end of the arm;
• a light sensor disposed in the sensor body and the sensor body having an inlet disposed opposite the light sensor, the inlet being positioned to receive and direct light towards the light sensor;
• and
• a beam dump positioned at the distal end of the arm opposite the light source to absorb at least a portion of the light beam directed towards the distal end of the arm, thereby preventing the absorbed portion of the light beam from being reflected back towards the inlet;
• wherein the arm includes a shelf that is disposed intermediate between the sensor body and the distal end of the arm, the shelf being configured to partially restrict a field of intake of light at the inlet.