Siemens SITRANS Series - 4.4.3 Measuring cell operation

● You can make an uninterrupted current measurement with a low resistance ammeter at
the connection ⑩.
● The measuring cell-specific data, electronics data and parameter assignment data are
saved in two EEPROM modules. The first EEPROM module ⑥ is linked to the measuring
cell, the second EEPROM module ⑪ to the electronics.
Operation
● The buttons⑧ can be used to call up individual functions.
● If you have a device with a display ⑨, you can view the measurement results, parameter
values and messages.
● With a computer and HART modem ⑦, you can operate the device via the engineering
system (e.g. SIMATIC PDM).
4.4.3 Measuring cell operation
WARNING
Destruction of the seal diaphragm
Danger of injury or damage to device
If the seal membrane is destroyed, the sensor may also be destroyed. If the seal membrane
is destroyed, no reliable measured values can be output.
Hot, toxic and corrosive process media can be released.
● Ensure that the material of the device parts wetted by the process medium is suitable for
the medium. Refer to the information in section Technical data (Page 191).
● Make sure that the device is suitable for the maximum operating pressure of your system.
Refer to the information on the nameplate and/or in Technical data (Page 191).
● Define maintenance intervals for regular inspections in line with device use and empirical
values. The maintenance intervals will vary from site to site depending on corrosion
resistance.
WARNING
Wetted parts unsuitable for the process medium
Danger of injury or damage to device.
Hot, toxic and corrosive media could be released if the process medium is unsuitable for the
wetted parts.
● Ensure that the material of the device parts wetted by the process medium is suitable for
the medium. Refer to the information in section Technical data (Page 191).
In the following sections, the process variable to be measured is called general inlet pressure.
Description
4.4 Functional principle
SITRANS P320/P420 (mA/HART)
30 Operating Instructions, 06/2018, A5E44852162-AA