Samson Media 6 Z, Инструкция по монтажу и эксплуатации

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8 EB 9527-3 EN
Design and principle of operation
3 Design and principle of oper-
ation
Differential pressure meters are used to mea-
sure and indicate differential pressure as
well as derived measured variables for gases
and liquids.
Measurement tasks
Liquid level measurement in stationary pres-
sure vessels and in pressure vessels on trans-
portation vehicles, in particular for cryogen-
ic gases, such as argon, oxygen, and nitro-
gen.
− Differential pressure measurement be-
tween flow and return flow pipe
−
Pressure drop measurement across valves
and filters
−
Flow rate measurement according to the
differential pressure method
The device mainly consists of the dp cell with
measuring diaphragm, range springs sized
according to the measuring span as well as
the indicating unit with two-wire transmitter
(4 to 20 mA output signal) and an LCD. The
power supply U
B
is 12 to 36 V DC. Option-
ally, battery operation
1)
with 9 V DC, with-
out 4 to 20 mA output signal.
The differential pressure ∆p = p
1
– p
2
creates
a force at the measuring diaphragm (1.1),
which is opposed by the range springs (1.2).
The movement of the measuring diaphragm
and lever (1.3), which is proportional to the
differential pressure, is transmitted by the
elastic disk (1.4) out of the pressure chamber
and converted into an electric signal by the
travel sensor (2).
Based on the evaluation of the data saved in
the FRAM (4), the electric signal is processed
by a microprocessor (3). It controls both the
LCD (7) and the D/A converter (9) for the
output signal, which is issued as a 4 to
20 mA two-wire transmitter signal at con-
nector A.
The serial interface (10) allows the device to
be configured with the TROVIS-VIEW soft-
ware using a special memory pen or a cable
connection to a computer. The user-specific
data are saved in the memory (FRAM) (4).
Data backup is also possible. The data re-
main saved until they are overwritten again.
This allows operating data to be easily ex-
changed on site between Media 6 and the
memory pen, and vice versa. The memory
pen can be programmed on a computer us-
ing the TROVIS-VIEW software.
The operating data allow the differential
pressure to be converted into values propor-
tional to the tank capacity or flow rate
2)
and
displayed or issued as a 4 to 20 mA signal.
The DIP switches (6) are used to select four
saved gas types and different write protec-
tion functions for saved data.
Three operating keys (5) are used to adjust
different operating functions (zero and span
adjustment, filling limit during operation,
limit contacts, and test function settings etc.)
as well as set different operating states (load
or save operating values).
1)
Operating mode: liquid level measurement
2)
Counting pulse (Media 6 Z)