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Thank you for choosing a HiTECH/ NIVELCO instrument.
We are sure that you will be satisfied throughout its use.
1. INTRODUCTION
A
PPLICATION
The EASYTREK SCD - 300 series compact ultrasonic transmitters from HiTECH/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 Total beam angle of 5
°
at –3 dB is a feature of all HiTECH/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.
P
RINCIPLE OF
O
PERATION
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.
rr
D
X
D
5 m
0,7 m
10 m
1,2 m
20 m
2 m
30 m
3 m
40 m
3,8 m
50 m
4,7 m
X
Diameters corresponding to the
5° beam angle
X = 16,5 ft. D = 28.0”
X = 33.0 ft. D = 4.0 ft.
X = 65.0 ft. D = 7.0 ft.
X = 99.0 ft. D = 9.9 ft.
X = 131.0 ft. D = 13.0 ft.
X = 197.0 ft. D = 15.0 ft.
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 unfavourable 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.
Содержание EasyTREK SCD-300 Series
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