KROHNE BM 90 EN - Manual (Page 3)

1. Introduction
1.1. Level-Sonic BM90
The KROHNE S.A. Level-Sonic BM90/BM90E is a multipurpose liquid level measurement and flow control instrument.
The KROHNE S.A. Level-Sonic BM90L/BM90LE is also available for powder and granulate level.
It consists of two main elements, a microprocessor based transceiver and a high-efficiency transducer.
Ultrasonic pulses are transmitted by the transducer to the surface of the material to be monitored and, within millisec-
onds, are reflected back to the transducer. The time period between transmission and reception of the pulses is
directly proportional to the distance between the transducer and the material.
The Level-Sonic BM90 microprocessor computes this time period continuously for all echoes received and analyses
which is the correct reflection from the surface being monitored. It uses this data as the basis for giving control outputs
and displays, in useable engineering units.
Level-Sonic BM90 is capable of the following functions :
a) Level Measurement
b) Volume Measurement
c) Distance Measurement
d) Pump Control
e) Differential Level Measurement
f ) Open Channel Flow Measurement
W A R N I N G
DO NOT OPEN THE ELECTRICAL COVER WHEN THE POWER IS ON TO
THE SUPPLY OR RELAY TERMINALS.
NOTE : There is no need to remove the upper cover. If you need to access to the RS232 or RS485 terminal for the
BM90L then you have to open it.
IN THIS EVENTUALLITY, PLEASE REMOVE IT GENTLY, A FLAT CABLE IS ATTACHED TO THE COVER. TAKE
CARE NOT TO DESTROY IT.
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