Optoelectronic Level Switches Model Type OPG01 OPG02 OPG03 OPG05 OPG051, OPG052 OPG06, OPG061 " width="302" height="364" class="so-widget-image" style="max-width:100%; height:auto; display:block" /> Optoelectronics Level Switches The electro-optic sensor contain an infrared LED and a light receiver. Light from the LED is directed into a prism which forms the tip of sensor. In case no liquid present, light from the LED is reflected within the prism to the receiver. When rising liquid immerses the prism, the light is refracted out into the liquid, leaving little or no light reach the receiver. Sensing this change, the receiver actuates electronic switching within the unit to operate an external alarm or control unit. Application Limit level detection of liquids and powdery or fine-granular bulk material, such as aggressive medium, acids and bases, water, aqueous solutions, liquids for cleaning, plastic granules etc.