INM 9370-RD Rev 5
13
Note
: Figure 4.5 shows the screw-terminal ‘-PS’ enclosure option, but the ‘-PC’
cage-clamp terminal arrangement is similar.
Check Section 4.2.2 on page 8 to confirm that the chosen fieldbus-ground option
is correctly wired, and adjust if necessary.
a) Tighten the gland securing nut(s), ensuring that any cables are not strained.
b) Replace the transparent protective cover over the terminal block and secure it
with the retaining screw to a recommended torque of 0.6 Nm.
4.4 Trunk Terminator module 9378-FT
If the enclosure provides the last (or only) spur connections on the segment, the
trunk must be terminated correctly to ensure that the optimum signal quality is
maintained. The Trunk Termination Assembly (TTA) has provision for an 9378-FT
Terminator module to be fitted when required.
NOTE
A terminator should be used only at the end points of the trunk wiring.
Connecting a terminator at any other point on the trunk will degrade the
signal.
The 9378-FT is a two-pin module that plugs into the upper end face of the Trunk
Terminator Assembly. See Section 5.3 on page 17 for fitting and removal details.
4.5 Trunk Surge module 9376-SP
The 9376-SP Trunk Surge module can be fitted to the TTA to prevent damage to the
equipment from voltage and current surges that could occur on the trunk wiring.
The 9376-SP is a four pin module that plugs into the upper end face of the Trunk
Terminator Assembly. See Section 5.3 on page 17 for fitting and removal details.
4.6 Spur connections
Refer to Figure 4.7 for additional details.
The spur cables can be connected directly onto the fieldbus barrier carrier or
through a Spur Surge module (FS32). If Spur Surge modules are not used, Section
4.6.2 on page 14 can be ignored.
4.6.1 Connecting the spur cables
Prepare the spur cables in accordance with the gland manufacturer’s instructions
and secure the cables in the glands.
IMPORTANT
•
When fitting the cable in the gland allow 20 – 30mm of available cable length
outside the enclosure to allow for cable adjustment if a Spur Surge module
is taken out of circuit inside the enclosure. See Section 5.4.1 on page 19 for
further details
•
Cable ferrules must be fitted to any stranded cable or screen wiring that is
being used.
Connect the prepared ends of the fieldbus spur cables into the ‘+’, ‘S’ and ‘–’
terminals on the carrier (or surge module, if fitted), making sure that the same
polarity is observed for all spurs.
