LLE102101

The LLE102101 is an enhanced Liquid Level Sensor incorporates a photo-transistor trigger which provides a digital output that denotes the presence or absence of liquid. This sensor incorporates reverse polarity, over voltage, short-circuit and transient protection. The mode of operation is derived from the principle of total internal reflection. An LED and phototransistor are housed within a plastic dome at the head of the device. When no liquid is present, light from the LED is internally reflected from the dome to the phototransistor. When liquid covers the done, the effective refractive index at the dome liquid boundary changes, allowing some light from the LED to escape. Thus the amount of light received by the phototransistor is reduced and the output switches, indicating the presence of liquid. This method of liquid level sensing is very fast and almost instantaneous in water.

• Solid state reliability, no moving parts
• Miniature size
• Very large choice of sensing media
• Fast response time
• Accurate and repeatable switching point
• Easy to install, saving assembly time
• High in air output type
• 250mm lead wires termination type
• Vamac rubber seal washer
• 5mA nominal supply current
• -40 to 125°C temperature range