18
19
INM MTL9373-FB3 Rev 1
INM MTL9373-FB3 Rev 1
5.7 Final checks
Before fitting/closing the lid on the barrier enclosure, check that:
• all wire terminal connection screws are sufficiently tightened.
• all enclosure cable glands and any blanking plugs are tightened to provide a
good seal.
• there are no loose cable ends that could cause an open or short circuit.
• the protective trunk wiring cover is in place and secure.
• no tools (e.g. screwdrivers) or loose items have been left in the enclosure.
• there is no damage to any enclosure cover seal, otherwise it must be replaced
with one that has the same manufacturer’s part number.
• if, and only if, a barrier is the last one on the fieldbus segment, ensure that its
termination link is installed correctly.
• the required grounding link is securely connected both inside and outside the
enclosure body.
Fit the enclosure lid and tighten all of its securing screws to their
recommended torque.
6
MAINTENANCE
When an enclosure containing a Fieldbus Barrier module is installed in a hazardous
area it is important for personnel to understand what activities are permissible when
fieldbus power is present and what are not.
WARNING!
Read and understand what work is permitted on the barrier module.
Failure to comply with these instructions can endanger the lives or health
of personnel and risk damage to the plant and the environment
6.1 General
The only items that can be disconnected, or removed, while the trunk is still powered
are:
•
Spur
wiring or
• FS32
Spur
Surge Protection modules.
All other wiring to the barrier requires the trunk power to be isolated, or a gas
clearance certificate to be obtained before any work is carried out.
6.2 Spur connections
All of the spur connections are intrinsically safe and therefore may be live-worked in a
hazardous area without ‘gas clearance’, while complying with normal ‘permit to work’
procedures.
If spur wiring is removed from a connecting plug, ensure that the same polarity is
observed when it is reconnected.
6.2.1 Removing a Spur Surge module
Use the following procedure and reference to Section 4.6 may help.
1. Loosen the two screws securing the pluggable, spur-wiring connector to the
Spur Surge module and unplug it.
2. Plug the Spur Surge module into the vacant socket on the barrier and
tighten the two fixing screws and its grounding screw, all to a recommended
torque of 0.5 - 0.6 Nm.
3. Plug the spur connecting plug into its mating socket on the Spur Surge
module and tighten the fixing screws to a recommended torque of
0.5 - 0.6 Nm.
Make any necessary adjustments to the spur cable to avoid any tension.
6.2.2 Adding a Spur Surge module
Use the following procedure and reference to Section 4.6 may help.
a) Loosen the two screws securing the pluggable, spur-wiring connector to the
barrier and unplug it.
b) Plug the Spur Surge module into the vacant socket on the barrier and tighten
the two fixing screws and its grounding screw, all to a recommended torque
of 0.5 - 0.6 Nm.
c) Plug the spur connecting plug into its mating socket on the Spur Surge
module and tighten the fixing screws to a recommended torque of
0.5 - 0.6 Nm.
Make any necessary adjustments to the spur cable to avoid any tension.