Eaton MTL CROUSE-HINDS Series User manual

937x-FB2-Px-SS
Fieldbus Barrier System
6-spur & 12-spur, Stainless Steel enclosures
November 2016
INM 937x-FB2-Px SS Rev 1
Instruction manual
MTL fieldbus networks

INM 937x-FB2-Px-SS Rev 1
ii
DECLARATION OF CONFORMITY
A printed version of the Declaration of Conformity has been provided separately within the original shipment of
goods. However, you can find a copy of the latest version at http://www.mtl-inst.com/certificates

INM 937x-FB2-Px-SS Rev 1 iii
CONTENTS
DECLARATION OF CONFORMITY ......................................................II
GENERAL SAFETY INFORMATION ...................................................IV
1 OVERVIEW ................................................................1
2 DESCRIPTION .............................................................2
3 MECHANICAL INSTALLATION ................................................2
3.1 Mounting overview ....................................................................2/3
3.2 Permitted enclosure combinations ......................................................3/4/5
3.3 Preparation .............................................................................6
3.4 Mounting...............................................................................6
3.4.1 Fixing the enclosure to a surface ...........................................................6
4 INITIAL ELECTRICAL INSTALLATION ..........................................7
4.1 Preparation .............................................................................7
4.2 Grounding ..............................................................................7
4.2.1 Protective local ground .................................................................7/8
4.2.2 Cable shield ground .....................................................................8
4.2.2.1 Single point of grounding at host; trunk & spur shields interconnected ........................8/9
4.2.2.2 Trunk shield grounded at host; spur cable shields grounded at barrier ...........................9
4.3 Trunk connections .......................................................................9
4.3.1 Trunk Terminal Assembly (TTA) ..........................................................9/10
4.3.2 Trunk wiring ...........................................................................11
4.4 Trunk Terminator F93-XE .................................................................11
4.5 Trunk Surge module 9376-SP .............................................................12
4.6 Spur connections .......................................................................12
4.6.1 Connecting the spur cables...............................................................12
4.6.2 Fitting FS32 Spur Surge modules..........................................................12
4.7 Blanking plugs .........................................................................13
4.8 Final checks............................................................................13
5 MAINTENANCE ...........................................................14
5.1 General ...............................................................................14
5.2 Fieldbus Barrier - fitting and removal ....................................................14/15
5.2.1 Removing a Fieldbus Barrier module (refer to Figure 5.1) ......................................15
5.2.1.1 Fitting a Fieldbus Barrier module (refer to Figure 5.1) .........................................15
5.3 Trunk Surge Protection module ...........................................................15
5.3.1 Fitting and removal .....................................................................15
5.3.1.1 Mounting a module .....................................................................16
5.3.1.2 Removing a module .....................................................................16
5.4 Spur connections .......................................................................16
5.4.1 Removing a Spur Surge module & spur cable adjustment .....................................16
5.4.2 Adding a Spur Surge module & spur cable adjustment .......................................16
5.5 Trunk connections ......................................................................17
5.6 Regular Maintenance checks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
6 TROUBLESHOOTING ......................................................18
7 ATEX INFORMATION.......................................................19
7.1 General ...............................................................................19
7.2 Installation ............................................................................19
7.3 Inspection and maintenance ..............................................................20
7.4 Repair ................................................................................20
7.5 Marking ............................................................................20/21

INM 937x-FB2-Px-SS Rev 1
iv
GENERAL SAFETY INFORMATION
Safety instructions for installation and operating personnel
The operating instructions provided here contain essential safety instructions for installation personnel
and those engaged in the operation, maintenance and servicing of the equipment.
WARNING !
Failure to comply with these instructions can endanger the lives or
health of personnel and risk damage to the plant and the environment.
WARNING !
The responsibility for planning, installation, commissioning, operation
and maintenance, particularly with respect to applications in explosionhazard
areas, lies with the plant operator.
Before commencing installation or commissioning:
• Read and understand the contents of this manual
• Ensure installation and operating personnel have received adequate training for this task
• Ensure that any operating instructions are fully understood by the personnel responsible.
• Observe national and local installation and mounting regulations (e.g. IEC 60079-14).
WARNING !
Before putting into service, all entries must be fitted with:-
1. ≥IP66 Ex eb tb Equipment certified blanking plugs or ≥IP66 Ex eb tb Equipment certified cable
glands. All blanking plugs and glands must have a minimum temperature range (-40°C to +75°C).
2. ≥IP66 Ex eb tb breather IECEx & ATEX equipment certified with a minimum temperature range of
-40°C to +75°C and IP rating (IP66) at least equal to that of the enclosure.
WARNING !
These assemblies may not be used in explosion-hazard area applications if they have been used
previously in general electrical installations.
During operation:
• Make the relevant instructions available at all times to the operating personnel.
• Observe safety instructions.
• Observe national safety and accident prevention regulations.
• Operate the equipment within its published specification.
• Servicing, maintenance work or repairs not described in this manual must not be performed without
prior agreement with the manufacturer.
• Any damage to this equipment may render its explosion protection null and void.
• No changes to any of the components that might impair their explosion protection are permitted.
If any information provided here is not clear:
Contact Eaton’s MTL product line or one of its representatives.
CAUTION!
These enclosures are supplied with the latest type of fieldbus barrier,
the 9377-FB-R. It is not possible to fit the earlier barrier type (model
9377-FB) into these enclosures.

INM 937x-FB2-Px-SS Rev 1 1
1 OVERVIEW
This manual explains the installation and maintenance procedures for the
937x-FB2-Px-SS Fieldbus Barrier range of enclosures and must be read in association
with the product datasheets that contain the electrical data. Any specials or variations
of the standard 937x-FB2-Px-SS will be covered within an Addendum section at the
end.
The 937x-FB2-Px-SS Fieldbus Barrier range of enclosures are field-mounted wiring
hubs offering a choice of six or twelve intrinsically safe spur connections, from
a single non-intrinsically safe trunk, for connection to FOUNDATION™ fieldbus
H1 fieldbus instruments. The incoming fieldbus trunk and the output spurs may
optionally be fitted with surge-protection devices.
The enclosure material used for the wiring hubs is stainless steel (SS) and they are
capable of being installed in a Zone 1 or Zone 2 hazardous area.
The following enclosure types are available by ordering the appropriate model
number.
• 9371-FB2-PS-SS Fieldbus Barrier system, 6-spur, Stainless Steel enclosure,
pluggable screw terminal connectors
• 9371-FB2-PC-SS Fieldbus Barrier system, 6-spur, Stainless Steel enclosure,
pluggable spring clamp connectors
• 9373-FB2-PS-SSFieldbus Barrier system, 12-spur, Stainless Steel enclosure,
pluggable screw terminal connectors
• 9373-FB2-PC-SS Fieldbus Barrier system, 12-spur, Stainless Steel enclosure,
pluggable spring clamp connectors
937x-FB2-Px-SS Fieldbus Barrier System
6-spur & 12-spur, Stainless Steel enclosures
Figure 1.1 - Enclosure example showing model 9373-FB2-PC-SS
Note: 9376-SP trunk surge protection module is optional and not supplied as
standard

INM 937x-FB2-Px-SS Rev 1
2
2 DESCRIPTION
The model numbers shown above comprise SS, increased safety, Ex e enclosures
containing either one (9371 models) or two (9373 models) carrier-mounted 9377-
FB-R fieldbus barrier modules. Each fieldbus barrier module converts a single, non-
intrinsically safe fieldbus trunk into six intrinsically safe (IS) spur connections for
connection to Foundation™ fieldbus H1 fieldbus instruments.
On passing through the enclosure wall, the incoming trunk wiring enters the Trunk
Terminal Area containing increased safety (Ex e) trunk wiring terminals. This assembly
is provided with a protective cover to deter interference, and carries a warning to the
user to isolate the power before working on any trunk wiring.
All enclosure models are supplied with a fieldbus Terminator module (part number F93-
XE) pre-installed in the Trunk Terminal area. This should remain installed if the enclosure
is at the end of the trunk segment. If the incoming fieldbus trunk will be onward linked
to a further node on the segment the terminator should be removed. Further details
are provided in Section 4 of this manual.
All spurs are galvanically isolated from the trunk allowing the user to choose the type
of grounding scheme most suitable to their system.
Short-circuit protection for each outgoing spur is built-in to the 9377-FB-R barrier
module, while surge protection is an option on individual spurs by installing Spur Surge
protection modules (part no. FS32).
A Trunk Surge Protection module (part no. 9376-SP) is another user option and this
can be plugged into a dedicated socket above the Trunk Terminal area to protect the
fieldbus barrier against damaging voltage and current surges on the incoming trunk
wiring.
The enclosures may be installed in a Zone 1 or Zone 2 hazardous area, in which case
the trunk wiring must consist of a suitably protected cable type together with the
appropriate environmental cable glands.
The Stainless Steel enclosure material provides excellent chemical and moisture
resistance and is suitable for use in a wide range of corrosive environments.
The enclosures 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 F800 or MTL 918x range of
redundant power supplies.
The enclosure is supplied pre-drilled for all trunk and spur cable entries and can be
supplied blank or fitted with Ex e certified nickel-plated brass blanking plugs and a
breather.
3 MECHANICAL INSTALLATION
See Figures 3.1 and 3.2 for the dimensions, fixing locations and cable gland positions
for both enclosure models.
3.1 Mounting overview
Before mounting an enclosure, consider the following points.
a) The permitted ambient temperature range external to the enclosure (–40°C to
+70°C) must not be exceeded. Avoid radiant heat by locating the enclosure away
from direct sunlight or local sources of heat.
b) The enclosure has an ingress protection rating of IP66 (to EN60529) so the
mounting location should be chosen to comply with this rating.
c) The enclosure is designed for mounting on a vertical surface, with the cable entry at
the lowest point, as shown in the upper part of Figure 3.1 or Figure 3.2.
d) The nominal weight of the enclosures, excluding any surge protection modules
(trunk or spur) is:

INM 937x-FB2-Px-SS Rev 1 3
Model type Nominal weight
9371-FB2-Px-SS 5.7 kg
9373-FB2-Px-SS 8.5 kg
e) Adequate security should be provided against unauthorised interference.
f ) All the necessary gland holes have been prepared in the enclosure.
WARNING !
It is not permitted to create additional holes in the enclosure as this
would violate the certification.
3.2 Permitted enclosure combinations
The maximum number of intrinsically safe spurs that can be supported per trunk
segment using 937x-FB2 range of Fieldbus Barrier enclosures is 18. The permitted
enclosure combinations are shown in Figure 3.3.
Figure 3.1 – External dimensions and mounting hole positions for
the 6-way enclosure 9371-FB2-Px-SS
371
345
306
271
30 186
11
TYP.
4 PLACES
306
138.5
9371-FB2
Fieldbus Barrier System, 6 Spur
SS Enclosure
TRUNK IN
TRUNK OUT
BREATHER
SPUR 2
SPUR 3
SPUR 4 SPUR 6
SPUR 1 SPUR 5

INM 937x-FB2-Px-SS Rev 1
4
30
271
186
508
482
443
11
TYP.
4 PLACES.
306
9373-FB2
Fieldbus Barrier System, 12 Spur
SS Enclosure
BREATHER
138.5
SPUR 12
SPUR 11
SPUR 10
SPUR 9
SPUR 8
SPUR 7
SPUR 6
SPUR 5
SPUR 4
SPUR 3
SPUR 2
SPUR 1
TRUNK OUT
TRUNK IN
Figure 3.2 – External dimensions and mounting hole positions for the 12-way
enclosure 9373-FB2-Px-SS

INM 937x-FB2-Px-SS Rev 1 5
9371-FB2
6-spur enclosure
Fieldbus instruments
Intrinsically
safe spur
Non-
intrinsically
safe trunk
T
T
Fieldbus
Power
Supply
9371-FB2
6-spur enclosure
1 2 3 6
Fieldbus instruments
Non-
intrinsically
safe trunk
9371-FB2
6-spur enclosure
1 2 3 6
Fieldbus instruments
Intrinsically
safe spur
9377-FB-R
Fieldbus Barrier module
(6-spur)
9377-FB-R
Fieldbus Barrier module
(6-spur)
Host
Control
System
T
Fieldbus
Power
Supply
Non-
intrinsically
safe trunk
9371-FB2
6-spur enclosure
1 2 3 6
Fieldbus instruments
Intrinsically
safe spur
9377-FB-R
Fieldbus Barrier module
(6-spur)
9371-FB2
6-spur enclosure
1 2 3 6
Fieldbus instruments
9377-FB-R
Fieldbus Barrier module
(6-spur)
T
9371-FB2
6-spur enclosure
1 2 3 6
Fieldbus instruments
9377-FB-R
Fieldbus Barrier module
(6-spur)
Host
Control
System
T
Fieldbus
Power
Supply
Host
Control
System
1 2 3 6
T
9377-FB-R
Fieldbus Barrier module
(6-spur)
T
Host
Control
System
Fieldbus
Power
Supply
9373-FB2
12-spur enclosure
1 2 3 6
Fieldbus instruments
Intrinsically
safe spur
Non-
intrinsically
safe trunk
1 2 3 6
Fieldbus instruments
9377-FB-R
Fieldbus Barrier module
(6-spur)
9377-FB-R
Fieldbus Barrier module
(6-spur)
T
9371-FB2
6-spur enclosure
1 2 3 6
Fieldbus instruments
9377-FB-R
Fieldbus Barrier module
(6-spur)
T
Host
Control
System
Fieldbus
Power
Supply
9373-FB2
12-spur enclosure
1 2 3 6
Fieldbus instruments
Intrinsically
safe spur
Non-
intrinsically
safe trunk
T
1 2 3 6
Fieldbus instruments
9377-FB-R
Fieldbus Barrier module
(6-spur)
9377-FB-R
Fieldbus Barrier module
(6-spur)
Figure 3.3 – Permitted enclosure combinations

INM 937x-FB2-Px-SS Rev 1
6
3.3 Preparation
a) Remove any temporary protection or packing materials.
b) The enclosure can be mounted on any suitable structure using the enclosure’s
integral mounting facilities.
c) The fixing bolts must be suitable for the mounting surface and the
environmental conditions.
d) It is advisable, before mounting, to do any necessary replacement of the cable
entry blanking plugs with suitable gland types. For further details
see Section 3.1 f).
3.4 Mounting
WARNING !
To minimise the risk of ignition by electrical apparatus in hazardous
areas, efficient installation, inspection and maintenance of apparatus
and systems is essential, and the work should be carried out by suitably
trained personnel in accordance with the prevailing code of practice.
The certification documents specify “Conditions for safe use” that must
be adhered to and the copy certificate supplied should be studied and
understood. Additionally it is recommended that a working knowledge
of IEC EN 60079 -14 be attained, as this standard provides guidance in
respect to the installation of electrical equipment in hazardous areas.
3.4.1 Fixing the enclosure to a vertical surface
Mark hole positions as shown in Figures 3.1 or 3.2.
Open up these hole positions to a suitable size and depth.
a) It is recommended that a washer, not exceeding the 11mm diameter specified
in Figures 3.1 and 3.2, is placed under the head of each of the bolts used to fix the
enclosure to its mounting surface.
b) It is suggested that the upper fixings should be put in place first then lower, so
that the enclosure can be supported by them.
After mounting the enclosure check that:
• It has not suffered any physical damage,
• The IP rating is not affected; for example, by distortion of the enclosure,
• The mounting bolts/nuts are all tightened as recommended above.

INM 937x-FB2-Px-SS Rev 1 7
4 INITIAL ELECTRICAL INSTALLATION
WARNING !
Before starting any electrical installation work, ensure that the incoming
trunk connection is isolated from any source of power.
CAUTION!
The temperature inside the enclosure could rise to 75°C.Ensure that all cables and
cable glands fitted are rated to withstand these temperatures.
4.1 Preparation
Loosen the captive screws of the enclosure lid and then remove it to obtain access
to the contents.
• The enclosure receives power from the incoming trunk cable and requires no
further source of power.
• The equipment shall only be powered from supplies that conform to
IEC 61158.
• Type ‘A’ fieldbus cable is recommended for fieldbus trunk and
spur connections.
• The terminal blocks for the trunk fieldbus cables have either screw terminal
connectors or spring clamp connectors according to the enclosure model
specified, but both are suitable for cables from 0.5mm2/AWG 20 up to
2.5mm2/AWG 14.
On completion of installation, check all blanking plugs and cable glands are
tightened to ensure IP rating of the enclosure is maintained.
For details of the enclosure wiring for the two system types.
4.2 Grounding
Two distinct grounding concepts should be recognised before wiring of the
enclosure begins:
a) A protective local ground – which is mandatory
b) Cable shield ground
These two concepts and their implementation are explained below.
4.2.1 Protective local ground
This ground connection is required to ensure that any exposed metal work in,
or on, the enclosure does not present a hazard to personnel; it also provides a
low impedance earth-grounding circuit for any surge protection items used in
the enclosure. An M8 earth-grounding stud is provided on the side wall of the
enclosure to enable a connection to be made to the local ground.
Use a ring terminal to make a good quality, plant safety earth connection (4mm2
cross-sectional area or better) to this bolt and tighten it to a recommended torque
of 5Nm.

INM 937x-FB2-Px-SS Rev 1
8
Note: It is important to prevent this connection from loosening and also to protect
it from corrosion.
Where the trunk and spur cables are protected by steel wire armour, this should
be treated as part of the “protective” ground. Normal practice is to bond the
armour to the plant structure at both ends of each cable. Where armour-protected
cables enter the Fieldbus Barrier enclosure, the armour must be connected to the
enclosure’s internal grounding plate using suitable cable glands.
4.2.2 Cable shield ground
The cable shield is normally electrically isolated from the protective earth ground
although in some cases the two may be deliberately interconnected, as explained
below. In both cases the trunk cable shields and the spur cable shields should be
connected to their appropriate terminals (‘S’) in the enclosure.
The enclosures can then be configured by the user to either of two grounding
methods. The user should adopt the one that conforms to their system’s normal
grounding method.
IMPORTANT: Whichever method is used, the screen/shield should only be grounded
AT ONE END of the cable. Grounding at both ends creates “ground loops”, which will
be troublesome and may even be dangerous.
The following options are available to the user.
WARNING !
The following may involve changes to wiring in the Trunk Terminal
Assembly. No part of the Trunk Terminal Assembly may be worked while
the enclosure is powered, unless the environment is known to be non-
hazardous.
4.2.2.1 Single point of grounding at host; trunk & spur shields interconnected
Figure 4.1 - Option 1
In many installations, the preferred method of grounding is to ground the fieldbus
cable shields at one point only, normally at the fieldbus power supply. In this case,
the trunk and spur cable shields are connected to each other at the Fieldbus Barrier
and are not connected to ground in the field. For this arrangement, insert the link as
shown in Figure 4.1.
Note: this is the default grounding method for factory-supplied
937x-FB2 enclosures.
Host
ground
Ground
stud
trunk shield
LK2
spur shields
LINK

INM 937x-FB2-Px-SS Rev 1 9
IMPORTANT NOTE
937x-FB2 enclosures are factory-supplied with Option 1 grounding. If power is
applied locally, for example during commissioning, when the trunk cable shield is
NOT providing a ground connection, the spur cable shields must (temporarily) be
grounded according to Option 2.
When the trunk cable shield ground has been fully instated (or restored), the
grounding method should be returned to Option 1.
4.2.2.2 Trunk shield grounded at host, spur cable shields grounded at barrier
Figure 4.2 - Option 2
With this arrangement, the fieldbus trunk shield is separated from the spur cable
shields. It should be adopted if plant or local regulations require that the spur cable
shields be grounded at the Fieldbus Barrier. For this arrangement, insert the link as
shown in Figure 4.2.
Note: After configuring the required grounding option, tighten the screw terminals to
a recommended torque of 0.6 Nm.
4.3 Trunk connections
Each enclosure is provided with two access holes for trunk cable glands; one for
the incoming trunk and another for onward linking to an additional enclosure, if
necessary.
WARNING !
No part of the Trunk Terminal Assembly may be worked while the
enclosure is powered, unless the environment is known to be
non-hazardous.
4.3.1 Trunk Terminal Area (TTA)
Inside the enclosure the trunk cables are terminated in a Trunk Terminal Area (TTA).
This is protected by a transparent cover with a warning label – both of these are
there to deter a user from working on the trunk connections without isolating trunk
power. See Figure 4.3.
Host
ground
Ground
stud
LINK
trunk shield
LK3
spur shields

INM 937x-FB2-Px-SS Rev 1
10
Figure 4.3 –TrunkTerminal Area connector details
Trunk cables pass through the enclosure wall via cable glands into the Trunk Terminal
Area.
Terminals are provided to allow a variety of wiring arrangements, according to the
particular requirements of the installation.
– “Trunk In” cable only
– “Trunk In” and “Trunk Out” cables
– Active and spare “Trunk In” cables
– Active and spare “Trunk In” cables with overall cable shield
– Active and spare “Trunk In” cables and “Trunk Out” cable
Figures 4.4 and 4.5 provide more details on the cable wiring options.
CAUTION!
THE ‘+’ AND ‘–’ WIRES OF A ‘SPARE’ TRUNK IN CABLE MUST BE CONNECTED
ONLY TO TERMINALS MARKED ‘NC’. THIS ENSURES THAT THE SPARE CABLE
IS NOT ELECTRICALLY CONNECTED IN PARALLEL WITH THE ‘ACTIVE’ TRUNK IN
OR TRUNK OUT CABLES. THE CABLE SHIELD OF THE SPARE CABLE SHOULD BE
CONNECTED TO AN ‘S’ TERMINAL.
ALL ‘SPARE’ TRUNK-IN CONNECTIONS (‘+’, ‘–’ AND SHIELD) MUST BE FIRMLY
GROUNDED AT THE HOST.
Local
ground
connection
Trunk (-)
terminals
Grounding
link
terminals
Trunk screen
terminals
Trunk (+)
terminals
F93-XE
Fieldbus
terminator
Overall
shield
Spare
Active
Trunk in
NC 1+ 1S 2S 3S2+ 1– 2– NC
Trunk in
Figures 4.4 - ‘Trunk In’ with Active & Spare
cable pair and overall cable shield
NC 1+ 1S 2S 3S2+ 1– 2– NC
Spare
Active
Trunk in Trunk out
Trunk in Trunk out
Figures 4.5 - Active & Spare ‘Trunk In’
cables plus ‘Trunk Out’ cable
Image to be updated

INM 937x-FB2-Px-SS Rev 1 11
4.3.2 Trunk wiring
Connect the trunk cable(s) in the following way.
• Remove the cover that protects the Trunk Terminal Area by applying
gentle pressure to the textured finger grips on each side of it: this releases the
catches from the recesses in the carrier housing, so that the cover may be lifted
away to reveal the trunk terminals. The cover is secured to the housing by a nylon
tie to avoid its loss or damage to it.
• Prepare the trunk cable(s) in accordance with the gland manufacturer’s
instructions and secure the cable(s) in the gland(s). Ensure that the cables are
not strained.
• Connect the prepared ends of the fieldbus trunk cable(s) into the appropriate
‘+’ , ‘–‘ and ‘S’ terminals, shown in Figures 4.4 or 4.5. The spring clamp (-PC
option) terminals are operated by inserting a narrow-blade screwdriver into
the upper opening, and lifting it to open the spring clamp in the terminal entry.
Insert the cable ferrule while the clamp is open, and release. Check that the
ferrule is securely held by applying gentle pressure to withdraw it.
Note: Figure 4.3 shows the PC options.
• Check Section 4. 2 to confirm that the chosen fieldbus ground option is
correctly selected, and adjust if necessary.
4.4 Trunk Terminator F93-XE
If the trunk is being looped onward to another enclosure then no fieldbus terminator
is required, but if the enclosure is the last (or only) enclosure on the trunk segment,
the trunk must be terminated correctly to ensure that the optimum signal quality
is maintained. The Trunk Termination Area has provision for a fieldbus terminator to
be fitted when required. Terminator model F93-XE is used with these enclosures to
provide the correct termination on the trunk segment.
Figure 4.3 shows the location of the terminator connection terminals and Figure 4.6
shows the fitting of the module. To fit the terminator, loosen the securing screws
in the two allocated terminals and insert the terminator, with the terminator body
facing towards the top of the assembly. Tighten the securing screws. Note that the
terminals for the terminator are always screw-terminal type, regardless of whether
the Fieldbus Barrier is a –PS (screw terminal) or –PC (spring clamp) version.
Figure 4.6 – Fitting an F93-XE terminator module
Check all connections then replace the Trunk Terminal cover by locating the clips into
the carrier housing slots then pushing it gently until the clips fully engage.
WARNING !
The F93-XE Terminator must not be removed or replaced while the
Fieldbus Barrier segment is under power, unless the area is known to be
non-hazardous
Trunk
terminals
Terminator
terminals
Terminator

INM 937x-FB2-Px-SS Rev 1
12
4.5 Trunk Surge protection module 9376-SP
The 9376-SP Trunk Surge protection 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 for fitting and removal details.
4.6 Spur connections
The spur cables can be connected directly onto the fieldbus barrier carrier terminals
or, for additional protection from current surges, be connected through a Spur Surge
module (FS32) as shown in Figure 4.7. (Note that the connectors shown in this figure
are screw-terminal type.)
If Spur Surge modules are not being used, ignore sub-section 4.6.2.
Figure 4.7 – FS32 Spur Surge module on carrier
4.6.1 Connecting the spur cables
Prepare the spur cables in accordance with the gland manufacturer’s instructions and
secure each cable in a suitable gland in the enclosure wall.
IMPORTANT
• When fitting the cable in the gland allow 20 – 30mm of additional cable length
outside the enclosure to allow for adjustment if a Spur Surge module is taken
out of circuit inside the enclosure. See Section 5.4.1 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.
4.6.2 Fitting FS32 Spur Surge modules
Spur Surge modules are pluggable units that integrate easily with the standard
pluggable connector and which direct excessive spur surge currents to the protective
local ground.
To fit an FS32:
1. Unscrew the two captive screws securing the standard pluggable connector
(supplied on the carrier) and remove it from its socket.
2. Insert the FS32 module into the now vacant socket on the carrier, tighten
the two side securing screws and the central “protective ground” screw, to a
recommended torque of 0.4 Nm.
3. Fit the connector (removed at Step 1 above) into the socket on the FS32 and
tighten its two securing screws also to a recommended torque of 0.4 Nm.
4. Removal of a Spur Surge module is the reverse of the fitting process. See
also Section 5.4.1 on page 14 for information on cable ‘adjustment’ if one of
these modules is taken out of use.

INM 937x-FB2-Px-SS Rev 1 13
4.7 Blanking Plugs.
Blanking plugs of factory-supplied Fieldbus Barriers are lightly tightened for ease of
removal. Any blanking plugs that are not removed from the fieldbus barrier must be
tightened to the required torque to meet the IP rating.
Two types of blanking plug are supplied with the Fieldbus Barrier as shown in figures 4.8
and 4.9 below and should be tightened to a torque rating as shown in the table below.
Type A 4.8Nm
Type B 12Nm
4.8 Final Checks.
Before replacing the lids on the enclosure, check:
• that all wire terminal connection screws have been tightened.
• that all cable glands are tightened to provide the required IP seal in accordance with
gland installation instructions.
• that there are no loose cable ends that could cause an open or short circuit.
• that the protective trunk wiring cover is in place on theTrunkTerminal Assembly.
• that no tools (e.g. screwdrivers) or loose items have been left in the enclosure.
• that there is no damage to any cover seal, otherwise it must be replaced with one
that has the same manufacturer’s part number.
• that if, and only if, the enclosure is the last one on the fieldbus segment, that a
9378-FTTerminator module is fitted into the socket on theTTA.
• that the required grounding link is securely connected between the enclosure lid and
the enclosure body.
Fit the enclosure lid and tighten all of its securing screws to a recommended
torque of 2.5 Nm.
Figure 4.8 - Type A Blanking plug Figure 4.9 - Type B Blanking plug

INM 937x-FB2-Px-SS Rev 1
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5 MAINTENANCE
When the enclosure 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 inside the enclosure.
Failure to comply with these instructions can endanger the lives or
health of personnel and risk damage to the plant and the environment.
5.1 General
The following items in the enclosure may be removed or disconnected while the
trunk is still powered.
• 9377-FB-R Fieldbus Barrier module(s)
• 9376-SP Trunk Surge module
• FS32 Spur Surge modules and any spur wiring
All other wiring in the enclosure requires the trunk power to be isolated, or a gas
clearance certificate to be obtained before any work is carried out.
5.2 Fieldbus Barrier - fitting and removal
CAUTION!
THESE ENCLOSURES ARE SUPPLIED WITH FIELDBUS BARRIER
MODULE TYPE 9377-FB-R
IT IS NOT POSSIBLE TO FIT THE EARLIER BARRIER TYPE (MODEL 9377-FB) INTO
THESE ENCLOSURES.
The individual 9377-FB-R Redundant Fieldbus Barrier module(s) may be fitted or
removed without isolating the trunk power. The trunk connections to the barrier
module on the carrier have spark suppression by design and cannot cause ignition
while they are being connected or disconnected.
Figure 5.1 – Fieldbus Barrier module – fitting & removal

INM 937x-FB2-Px-SS Rev 1 15
5.2.1 Removing a Fieldbus Barrier module (refer to Figure 5.1)
a) Loosen the three captive fixing screws (C & D) on the module to release it.
The screws are all spring-loaded and should retract when the thread
has disengaged.
b) Slowly pull the 9377-FB-R Fieldbus Barrier module away from its connections
on the carrier until the safety retaining clip (B) stops further removal.
c) Press the clip (see bold black arrow) towards the module until the barrier is
released and can be removed completely.
5.2.1.1 Fitting a Fieldbus Barrier module (refer to Figure 5.1)
Note: Before fitting a 9377-FB-R Fieldbus Barrier module check the connection pins
on its underside to ensure that they have not been bent or damaged in any way.
Do not use, or attempt to repair, a barrier module that has any of its pins bent or
damaged, because this might affect its safety and will invalidate the certification.
a) Engage the locating guides (A) of the 9377-FB-R Fieldbus Barrier module into
the sockets provided on the carrier and push the module fully into place.
b) Tighten the three captive fixing screws (C & D) to a recommended torque of
0.9Nm to secure it.
5.3 Trunk Surge Protection module
Figure 5.2 –Trunk Surge Module connectors and retaining clips
5.3.1 Fitting and removal
The module has connectors that are designed to prevent an ignition-capable spark
when the module is installed or removed.
Do not use, or attempt to repair, a module that has any of the pins on its underside
bent or damaged, because this might affect its safety and invalidate the certification.
Figure 5.3 – Fitting and removal ofTrunk Surge Module
Front clip
Rear clip
Safety
retaining clip
loop

INM 937x-FB2-Px-SS Rev 1
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5.3.1.1 Mounting a module
Refer to Figure 5.3.
Orientate the module so that the smaller front clip is facing the trunk terminals, then:
• push the module so that the safety retaining clip on the carrier housing fits into
the loop on the module
• locate the terminal pins into their contact sockets on the carrier housing and
• push the module home until front and rear retaining clips engage.
5.3.1.2 Removing a module
Refer to Figures 5.2 and 5.3 for further information.
Removal is a two-step process that first breaks the electrical connection, followed by
the physical removal of the module from the housing.
• Press the clip at the top of the module and tilt the module forward until the clip
disengages at the rear
• Press the front clip and withdraw the module from its socket until it is stopped
by the safety retaining clip
• Press down on the safety retaining clip enough to release it, then pull the
module away from the carrier housing without rotating or twisting it.
5.4 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.
5.4.1 Removing a Spur Surge module & spur cable adjustment
If an FS32 Spur Surge module needs to be removed from circuit, it will probably be
necessary to increase the cable length inside the enclosure slightly to allow the spur
wiring connector to be plugged into the circuit board. Use the following procedure.
a) Loosen the two screws securing the pluggable, spur-wiring connector to the
Spur Surge module and unplug it.
b) Loosen all three of the Spur Surge module’s fixing screws and unplug it from
the carrier.
c) Loosen the spur cable gland.
d) Pull an additional 20 mm (approx.) of additional cable length into the enclosure.
e) Plug the spur connecting plug into its mating socket on the barrier carrier and
tighten the fixing screws to a recommended torque value of 0.4 Nm.
Make any final adjustments to the cable, to avoid any tension, then tighten the spur
cable gland to clamp the cable to retain the IP rating of the enclosure.
5.4.2 Adding a Spur Surge module & spur cable adjustment
If an FS32 Spur Surge module is added, it will probably be necessary to reduce the
cable length inside the enclosure slightly when connecting the spur wiring connector
to the Spur Surge module. Refer also to Section 4.6.1 for further fitting details.