Figure 5-7
Electrical wiring with external T-connector
A maximum of 32 field devices may be connected per fieldbus segment (cf. IEC 61158-2 (MBP)).
However, this number may be restricted due to type of ignition protection, bus power option,
current consumption of field device etc.
A maximum of four field devices can be connected to a spur.
Wiring
• Install bus terminations at each end of the cable (Terminations are not included in the scope
of delivery).
With various junction boxes (not Ex-rated), the bus termination can be activated via a switch.
Otherwise a separate bus terminator must be installed.
Note
If the fieldbus is extended with a repeater, the extension must also be terminated at both
ends.
If the bus segment is branched, the device furthest from the segment connector represents
the end of the bus.
• Connect shielding with the nearest reference ground.
CAUTION
Bus shielding
The specified immunity and radiated emission are only guaranteed if the bus shielding is
fully effective. This includes connecting the shields to the metal connections of the device
but also laying the shields to the terminal compartment, distributor, DP/PA coupler or DP/PA
link.
CAUTION
Potential equalization
A suitable potential equalizer must be provided to avoid potential differences between the
individual plant parts and thus the risk of malfunctioning. Refer to EN 60364-4-41 & EN
60364-5-54.
Connecting
5.3 Wiring PROFIBUS PA
SITRANS FUS060 with PROFIBUS PA
38
Operating Instructions, 09/2021, A5E02225054-AD