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Thank you for choosing a NIVELCO instrument.
1.
INTRODUCTION
The EasyTREK SCD–300 series compact ultrasonic transmitters from NIVELCO are designed to measure the level of free flowing solids, granules and
powders. The unit does not touch the material to be measured and does not include any moving parts. Thus, it is not exposed to mechanical loading, no
abrasive effect is expected and regular maintenance is not required.
A beam angle of 5
at –3 dB is a feature of all NIVELCO’s ultrasonic sensors designed for the level measurement of free flowing solids.
This uniquely narrow beam angle ensures reliable measurement in narrow silos with uneven side walls or sometimes even in the presence of dusting.
Furthermore, as a result of the narrow beam angle – the emitted ultrasonic signals have an outstanding focusing – a sufficient signal penetration through dust is
ensured. Modifying of the factory default settings of the level transmitter is possible
only via HART communication
.
O
PERATION PRINCIPLE
The ultrasonic level metering technology is based on the principle of
measuring the time required for the ultrasound pulses to make a round trip
from the sensor to the level to be measured and back.
The sensor emits an ultrasonic pulse train and receives the echoes reflected.
The intelligent electronic device processes the received signals by selecting
the echoes reflected from the surface and calculates the distance from the
time of flight between the sensor and the surface of the medium. This is the
basis for all other output signals (level or volume) of the EasyTREK! For
measuring the level of the medium the greatest distance of the application (H)
has to be programmed.
Diameters corresponding to the
5° beam angle.
Minimum measuring distance (X
m
):
is the construction defined smallest distance within which measurement is not possible (Dead Band; see 5.3. Parameters
P05). In special applications this range should be extended with programming (close end blocking)
Maximum measuring distance (X
M
):
is the construction defined greatest distance, which can be measured by the unit under ideal conditions. No
measurement is possible over this distance i.e., maximum distance of the application H must not be greater than X
M
. Under unfavorable circumstances such as
bad reflection or heavy dusting of the material the measuring capability may be reduced up to the half of the unit’s best performance.
Summary of Contents for EasyTREK SCD-31 4 Series
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