3
INM9108 Rev 3
2.2 Module carrier
The module carrier provides fieldbus power for four fieldbus segments. It supports a pair of
redundant pluggable power supply and arbitration modules for each segment and all connection
facilities.
Each carrier has connections for redundant 24V input power supplies, ALF111 fieldbus
communication modules via AKB336 cables and intrinsically safe field trunks. A volt-free failure
alarm is also provided for connection to a digital input module in the host control system. There
are no active electronic circuits on the carrier, resulting in long calculated Mean Time to Failure
(MTTF) and overall high system availability.
The carrier dimensions (Figure 2.2) are designed to provide high packing density in typical
800mm wide equipment cabinets. Survival in high-vibration marine environments is achieved
by secure panel-mount fixings.
The FISCO power supply modules are pluggable versions of the MTL 9122-IS units applications,
and support the same level of features. These include a built-in repeater function for accurate
wave-shape transmission and communication error reduction, and three-way isolation between
bulk power, host and field trunks for elimination of cross-talk between segments. LED indicators
provide information on system health and assist with fault diagnosis.
3 INSTALLATION
WARNING !
This equipment must be installed, operated and maintained only by
trained competent personnel and in accordance with all appropriate
international, national and local standard codes of practice and site
regulation for intrinsically safe apparatus and in accordance with the
instructions contained here.
3.1 General
The 9108-22 power system may be mounted in a safe area or a Zone 2 IIB T4 hazardous area.
See also Section 6 - Appendix for further information. The mounting conditions must:
a. prevent any form of pollution that could compromise the operation of the unit. For example,
an unpolluted location or a suitable enclosure could be chosen.
b. provide an adequate level of mechanical protection. This can be achieved by selecting a
protected location, a suitable cabinet or enclosure, or a combination of both.
c. ensure that all cable entries and connections are secure by making provision for the careful
routing and securing of all cables.
d. provide adequate security against unauthorised interference.
e. ensure that the permitted ambient temperature range of the units (–20°C to +60°C) is not
exceeded. Be aware of the power dissipation in the equipment’s cabinet or enclosure and
consider the use of shading against direct sunlight, or even forced cooling.
3.2 Required tools
To remove or replace a FISCO or a SAM module a straight-bladed screwdriver is required with a
minimum shaft length of 130mm (5¼”) and a maximum blade diameter of 5mm (3/16”).
3.3 Mounting overview
Mount the 9108-22 assembly on a vertical surface with the orientation shown in Figure 2.2. Any
other orientation will reduce the permitted maximum operating temperature.
IMPORTANT: The mounting surface and any fixings must be capable of supporting the weight
of the complete assembly which is just under 5.5kg.
Four 7mm diameter slotted holes are provided in the backplate for mounting the assembly -
see Figure 3.1 - and access to the mounting screws is provided through the circuit board (after
removal of some modules). This feature allows the assembly to be fitted to, or removed from,
its mounting without removing the mounting screws.
Note: Because of the slotted mounting holes, 15mm of free space is required above the top
edge of the assembly to allow the backplate to be mounted and demounted.
