Infra-red Level Detector with 555

Posted on Jun 4, 2012

Useful for liquids level detection and proximity devices Up to 50 cm. range, optional relay operation. This circuit is useful in liquids level or proximity detection. It operates detecting the distance from the target by reflection of an infra-red beam. It can safely detect the level of a liquid in a tank without any contact with the liquid itself. The device`s range can be set from a couple of cm. to about 50 cm. by means of a trimmer. Range can vary, depending on infra-red transmitting and receiving LEDs used and is mostly affected by the color of the reflecting surface. Black surfaces lower greatly the device`s sensitivity.

Infra-red Level Detector with 555
Click here to download the full size of the above Circuit.

IC1 forms an oscillator driving the infra-red LED by means of 0.8mSec. pulses at 120Hz frequency and about 300mA peak current. D1 & D2 are placed facing the target on the same line, a couple of centimeters apart, on a short breadboard strip. D2 picks-

Leave Comment

characters left:

New Circuits



Popular Circuits

Low Loss Step Down Converter
water level circuit
intercom circuit with transistors
Network RJ45 Cable Tester Circuit
Electromagnetic Field Probe with Meter Output
Current-tampering circuit