Siemens DS Betriebsanleitung Seite 37

To permit fault-free communication, the bus must be terminated at both ends
(see Figure 2). This is already guaranteed at the control system end by the
bus terminator present in the coupler or link. An additional teminator must be
provided at the remote end of the bus.
!
Warning
Only approved bus terminators, junctions etc. may be used
for intrinsically-safe circuits.
The specified noise immunity and emitted interference are only guaranteed
when the bus screening is fully effective.
This includes connection of the screens to the metal housing of the
SITRANS P, as well as routing of the screens to the junction boxes,
distributors, coupler or link.
Appropriate equipotential bonding must be provided to avoid differences in
potential between the individual plant components and the associated
danger or limitation in functions. Information on dimensioning and execution
can be found in DIN VDE 0100 Part 410 and Part 540.
DIN VDE 0165 of 2/91 must be observed when installing electric plant in
potentially explosive atmospheres. Further information on the PROFIBUS
installation can be found in the PNO Manual (see Section 1.1.2).
SITRANS P
C79000-B5674-C207-1
Operating Instructions
33