Instruction manual

3
INM9380-RD-1
May 2012
Consequently, if a spur ‘fail-over’ occurs, an alarm is signalled quickly to the host, via
the fieldbus connection, to facilitate any necessary remedial action. The five remaining
spurs are available to the user for connection to field devices.
2.3 Trunk Terminal Assembly
The incoming trunk wiring is terminated inside a separate compartment, called the
Trunk Terminal Assembly (TTA), that contains increased safety (Ex e) trunk wiring
terminals. This compartment has a protective cover to deter interference, and carries
a warning to the user about working on trunk wiring without first isolating the power.
A fieldbus Terminator module (part no. 9378-FT) is supplied pre-fitted on the TTA. This is to
remain installed if the assembly is at the end of the segment. If the incoming fieldbus trunk
will be onward linked to a further node on the segment the terminator can be removed.
See Section 4.4 on page 10 for additional information.
An optional Trunk Surge module (part no. 9376-SP) can be plugged into the TTA to protect the
fieldbus barrier against damaging voltage and current surges on the incoming trunk wiring.
The 9387-FB-Px-R Fieldbus Barriers are bus-powered and require no additional power
supply in the field. When used with a fieldbus host control system, power for the trunk
MUST be provided only by a supply conforming to IEC 61158-2, e.g. MTL-Relcom F800
or 918x Series redundant power supplies.
3 MECHANICAL INSTALLATION
See Figure 3.1 for the dimensions, fixing locations and cable gland positions.
!
ABB
Axxxxxxx Pxxxxx Gxxxxx
Mxxxxx xxxxxxxxxxxxxx
TTH300
TRUNK
IN
TRUNK
OUT
ABB
A
B
230.0
385.0
355.0
240.0 260.0
266.0
410.0
99.3
Mounting slot size 14 x 6
Figure 3.1 - Dimensions and mounting hole positions for the assembly (9387-FB-Px-R)
3.1 Mounting overview
Before mounting an assembly, consider the following points.
a) When planning the layout of any protective enclosure for an assembly, ensure that
adequate space is provided for suitable cable management (e.g. trunking).
b) The permitted ambient temperature range for the assembly (–40°C to +75°C) must
not be exceeded. Avoid radiant heat by positioning an assembly and its enclosure
away from direct sunlight or local sources of heat.