Endress+Hauser PROline promag 53 - Potential Equalization; Standard Case

4 Wiring PROline Promag 53
56 Endress+Hauser
4.3 Potent ial equalization
4.3.1 Standard case
Perfect measurement is only ensured when the medium and the sensor have the same
electrical potential. Most Promag sensors have a standard installed reference electrode
which guarantees the required potential matching. This usually means that additional
potential matching measures are unnecessary.
Promag W:
Reference electrode is standard
Promag P:
• Reference electrode is standard for electrode materials 1.4435, Alloy C-22 and
tantalum.
• Reference electrode is optional for electrode material Pt/Rh.
Promag H:
• No reference electrode. The metallic process connection provides a permanent
electrical connection to the fluid.
• If the process connections are made of a synthetic material, ground rings have to be
used to ensure that potential is equalized (see Page 39). Ground rings are accesso-
ries which must be ordered separately → Page 97.
!
Note:
For installation in metal pipes, it is advisable to connect the ground terminal of the trans-
mitter housing to the piping.
Fig. 36: Potential equalization by means of the transmitter's ground terminal
"
Caution:
For sensors without reference electrodes or without metal process terminals, carry out
potential equalization as per the instructions for special cases described below. These
special measures are particularly important when standard grounding practice cannot
be ensured or extremely strong matching currents are expected.
F06-5xxxxxxx-04-xx-xx-xx-002