Answer / visakh ctjv

In ultrasonic level transmitter, a ultrasonic source is
used to produce ultrasonic pulses . these pulses are
transmitted through the vessel,the echo returning back
from the vessel is then recieved by a detector , depending
upon the level in the vessel the frequency of the recieved
signal varries ,the difference between the transmitted
pulse frequency and the recieved signal frequency is used
to measure the level.

Answer / hassanelect

The ideal mounting point for the sensor is directly
underneath the silo roof.
The ultrasonic emitter in the sensor is excited electrically
and sends an ultrasonic pulse in the direction of the
surface of the product. The surface partially reflects the
pulse. This echo is detected by the same sensor, now acting
as a directional microphone, and converted back into an
electrical signal.
The time between transmission and reception of the pulse -
the sonic run time - is directly proportional to the
distance between the sensor and the product surface.
The distance D is determined from the velocity of sound c
and the run time t by the formula:
D=C.t/2

Answer / naabil al-eryani

The transmitter is designed to be mounted above a liquid
and uses ultrasonic pulses to continuously measure the
distance to the liquid surface.
The microprocessor-controlled electronics calculates
distance to the liquid level from the time delay between
the transmitting and receiving of signals.

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