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TP302 – Operation, Maintenance and Instructions Manual
1.8
+
GROUND
TERMINAL
POWER
SUPPLY
TERMINALS
COMUNICATION
TERMINALS
Figure 1.8 – Wiring Block
The
TP302 uses the 31.25 kbit/s voltage mode option for the physical signaling. All other devices on
the same bus must use the same signaling. All devices are connected in parallel along the same
pair of wires.
Various types of Fieldbus devices may be connected on the same bus.
The TP302 is powered via the bus. The limit for such devices is 16 for one bus for non-intrinsically
safe requirement.
In hazardous area, the number of devices may be limited to 6 by intrinsically safe restrictions.
The
TP302 is protected against reverse polarity, and can withstand ±35 Vdc without damage.
WARNING
In hazardous areas with explosion proof requirements, the covers must be tightened with at least 8 turns. In
order to avoid the penetration moisture or corrosive gases, tighten the o-ring until feeling the o-ring touching the
housing. Then, tighten more 1/3 turn (120

) to guarantee the sealing. Lock the covers using the locking screw.
In hazardous zones with intrinsically safe or non incendive requirements, the circuit entity parameters and
applicable installation procedures must be observed.
Cable access to wiring connections is obtained by the two conduit outlets. Conduit threads should be sealed by
means of code-approved sealing methods. The unused outlet connection should be plugged and sealed
accordingly.
Should other certifications be necessary, refer to the certification or specific standard for installation limitations.
Bus Topology and Network Configuration
Bus and tree topology
are supported. Both types have a trunk cable with two terminations. The
devices are connected to the trunk via spurs. The spurs may be integrated in the device giving zero
spur length. A spur may connect more than one device, depending on the length. Active couplers
may be used to extend spur length.
Active repeaters may be used to extend the trunk length.
The total cable length, including spurs, between any two devices in the Fieldbus should not exceed
1900m.