Emerson MSP422 User Manual
Reference Manual
IP2013, Rev BA
February 2012
February 2012
Mobrey MSP422
www.mobrey.com
Section 2
Transmitter Overview
Theory of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 2-1
Components of the Transmitter . . . . . . . . . . . . . . . . . . . . page 2-2
Components of the Transmitter . . . . . . . . . . . . . . . . . . . . page 2-2
THEORY OF OPERATION
The Mobrey MSP422 ultrasonic level 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
measures the time delay between the transmitting and the receiving of the
reflected signals to calculate the distance (Figure 2-1).
above a liquid and uses ultrasonic pulses to continuously measure the
distance to the liquid surface. The microprocessor-controlled electronics
measures the time delay between the transmitting and the receiving of the
reflected signals to calculate the distance (Figure 2-1).
When programmed with the bottom reference of the application – usually the
bottom of a tank – the MSP422 computes the liquid depth (level) and outputs
a 4–20 mA signal proportional to that level.
bottom of a tank – the MSP422 computes the liquid depth (level) and outputs
a 4–20 mA signal proportional to that level.
An LCD screen inside the enclosure displays the selected measurement.
Programming of the MSP422 is achieved using the integral push-buttons
inside the enclosure and the menu system shown on the LCD screen.
Programming of the MSP422 is achieved using the integral push-buttons
inside the enclosure and the menu system shown on the LCD screen.
The MSP422 may be mounted in a non-hazardous areas only.
Figure 2-1. Typical Application
Using a Mobrey MSP422
Transmitter
Using a Mobrey MSP422
Transmitter
Di
st
ance
Lev
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l
Bo
tt
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Re
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