SITRANS LH300 (7MF1575..) Transmitter for hydrostatic level
A5E37897183-AA, 09/2016
7
3.3
Design of the nameplate
①
Article number
⑤
Type of protection
②
Characteristics for hazardous area
⑥
Group (gas, dust)
③
Serial number
⑦
Maximum surface temperature (temperature class)
④
Category for operating area
⑧
Group (gas)
Figure 3-1
Example of a nameplate
The pressure transmitter has a nameplate with the article number and other important information, such as design details
and technical specifications.
You must also observe the information in the relevant certificate for a transmitter version for use in hazardous areas.
3.4
Mode of operation
①
Sensor
①
Protective conductor connection/
Equipotential bonding
②
Connection for auxiliary power supply
②
Hydrostatic pressure
③
Vent pipe
Figure 3-2
Pressure transmitter, mode of operation and wiring diagram
On one side of the sensor
①
the diaphragm is exposed to the hydrostatic pressure
⑤
, which is proportional to the
immersion depth. This pressure is compared with the atmospheric pressure. Pressure compensation is carried out using the
vent pipe
③
in the connecting cable.
The hydrostatic pressure of the liquid column acts on the diaphragm of the sensor and transmits the pressure to the
Wheatstone resistance bridge in the sensor.
The output voltage signal of the sensor is fed to the electronics, where it is converted into an output current signal of 4 mA to
20 mA.
The protective conductor connection/equipotential bonding
④
is connected to the enclosure.
