MTL 9312-FB-ST-SS-SP User manual

Instruction Manual
INM9312
9312-FB-ST-SS-SP
Fieldbus Barrier

ii
CONTENTS PAGE
© 2008 MTL Instruments. All rights reserved.
INM9312-FB-SS-SP-1 Oct 2008 ii
1 General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Warning information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Symbols used. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.3 Definitions of terms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2 General safety information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1 Safety instructions for installation and operating personnel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3 Scope of application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.1 Intended use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4 Functional description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4.1 Power management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
5 Device construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
6 Transport, storage and disposal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
7 Mounting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
8 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
8.1 Examples of fieldbus segment topologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
8.2 Proof of intrinsic safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
8.3 Cable lengths for trunk and spurs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
8.4 Connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
8.5 Earthing / Grounding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
8.6 Fieldbus Terminating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
9 Commissioning and operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
10 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
10.1 Regular maintenance work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
10.2 Repair work. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
10.3 Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Appendix 1 - Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

1
INM9312-FB-ST-SS-1 Oct 2008
9312-FB-ST-SS-SP Fieldbus Barriers INM9312-ST-SS-SP-1
Oct 2008
1
1 GENERAL INFORMATION
1.1 Warning information
Warnings are occasionally provided in these operating instructions in the following manner:
They are always identified by the signalling word "WARNING“ and sometimes also have a symbol
which is specific to the danger involved.
1.2 Symbols used
 Action required - recommended user actions
 Reaction - the outcome of described actions
Energised parts!
Danger of explosion!
1.3 Definitions of terms
FOUNDATION fieldbusTM
Fieldbus protocol defined by the Fieldbus FoundationTM.
H1
The low-speed version of FOUNDATION fieldbusTM operating at 31,25kbits/s. H1 fieldbus has been widely
adopted in the process industries and is suitable for use in regulatory control and monitoring applications
in safe and hazardous areas.
Profibus-PA
One of the three vendor-independent fieldbus variants supported by the Profibus organisation.
Profibus-PA is intended for Process Automation and shares the same 31,25kbits/s physical layer
specification as FOUNDATION fieldbusTM H1.
Trunk
The main communication cable on a fieldbus segment. It is typically the longest cable path between any
two fieldbus devices.
Terminator
Network of components that are used at each end of a fieldbus segment to match the characteristic
impedance of the cable.
Spur
A branch cable connecting a fieldbus device to the fieldbus trunk. Spurs can be up to 120m in length.
Fieldbus power supply
A power supply that provides DC power onto a fieldbus trunk without interfering with the communications
signals. Combined with the two terminators, it conditions the trunk impedance to be compatible with
fieldbus instruments.
WARNING
The type and source of the danger!
The possible consequences
Ways to avoid the danger
Ex

2
INM9312-FB-ST-SS-1 Oct 2008 2
Fieldbus instrument
A field instrument that is capable of communicating in a fieldbus network. Typical fieldbus instruments
are valves and transmitters.
Host
The fieldbus control system, including the fieldbus interface card.
Segment
A section of fieldbus that is terminated in its characteristic impedance, meaning a cable and fieldbus
devices installed between a pair of terminators. Segments can be linked by repeaters to form longer
fieldbuses. The standard allows each segment to support up to 32 fieldbus devices, but many systems
limit this to 16 fieldbus devices.
DP/PA coupler
The DP/PA coupler connects a Profibus PA segment with a Profibus DP. The fieldbus power supply may
be integrated in the DP/PA coupler.
Master
The Profibus master is generally a process control system (PCS), a programmable logic controller (PLC)
or a PC.
Structure of a Foundation Fieldbus H1 segment
Structure of a Profibus PA segment
Host
Fieldbus
power
supply
Trunk (Foundation fieldbus H1)
Field devices
Power
Spurs
Power
(option)
Ter inator
Figure 1: - A FOUNDATION fieldbusTM segment
Host
Fieldbus
power
supply
Trunk (Profibus PA)
Field devices
Power
Spurs
Power
(option)
Ter inator
Figure 2: - A Profibus-PA segment

3
INM9312-FB-ST-SS-1 Oct 2008 3
2 GENERAL SAFETY INFORMATION
2.1 Safety instructions for installation and operating personnel
These operating instructions contain basic safety instructions for installation, operation and maintenance
and servicing. Failure to comply with these instructions can endanger personnel, the plant and the
environment.
Before installation/commissioning:
Read the operating instructions.
Give adequate training to the installation and operating personnel.
 Ensure that the contents of the operating instructions are fully understood by responsible
personnel.
The national installation and mounting regulations (e.g. IEC 60079-14) apply.
When operating the devices:
Make the operating instructions available at the installation area (at all times).
 Observe safety instructions.
 Observe national safety and accident prevention regulations.
 Operate the equipment within its published specification.
 Servicing/maintenance work or repairs which are not described in the operating instructions must
not be performed without prior agreement with the manufacturer.
 Any damage may render explosion protection null and void.
 No changes to the devices or components impairing their explosion protection are permitted.
 The device may only be fitted and used if it is in an undamaged, dry and clean state.
If there are any points which remain unclear:
 Contact the manufacturer.
WARNING
Risk due to unauthorised work being performed on the device!
There is a risk of injury and damage to equipment
Maintenance, installation, commissioning and servicing work must only be performed by personnel
who are both authorised and suitably trained for this purpose

4
INM9312-FB-ST-SS-1 Oct 2008 4
3 SCOPE OF APPLICATION
The series 9312-FB-ST-SS-SP Fieldbus Barrier is suitable for use in Zone 1 and Zone 2 hazardous
areas.
It is used for connecting up to eight intrinsically safe field devices to a non-intrinsically safe trunk;
providing galvanic isolation between the trunk and spurs.
3.1 Intended use
♦For all fieldbuses with a IEC 61158-2 physical layer, e.g. FOUNDATION fieldbus H1 and Profibus PA.
♦For non-intrinsically safe trunks, Ex e connections.
♦For intrinsically safe spurs (Ex i and FISCO), to connect intrinsically safe field devices.
Overview of explosion protection for Fieldbus Barrier, trunk and spurs
Fieldbus Barrier
Ex e / Ex i
Zone 0 Zone 1 Zone 2 non-hazardous
9312-FB-ST-SS-SP
with stainless steel
enclosure
not permitted permitted permitted permitted
Trunk not permitted Ex e Ex e permitted
Spurs Ex ia Ex ia Ex ia permitted
WARNING
When installing in an Ex e enclosure:
Affix an indication label (in accordance with IEC 60079-7):
"Non-intrinsically safe circuits protected by internal IP 30 cover."
WARNING
Use the Fieldbus Barrier only for its intended purpose!
The manufacturer’s liability and your right to make claims under warranty will be invalidated
Use the Fieldbus Barrier only under the conditions described in its operating instructions.
Other uses are not valid.

5
INM9312-FB-ST-SS-1 Oct 2008 5
4 FUNCTIONAL DESCRIPTION
Each 9312-FB-ST-SS-SP Fieldbus Barrier is used for connecting up to eight, intrinsically safe field devices
to a non-intrinsically safe trunk; providing galvanic isolation between trunk and spurs. Up to four 9312-
FB-ST-SS-SP Fieldbus Barriers may be connected in a filedbus segment, thereby providing up to 32
spurs.
The Fieldbus Barrier functions at the physical level only; it is independent of the protocol used. It can
therefore be used for every fieldbus that is compliant with IEC 61158-2. At this time, these include the
FOUNDATION fieldbus H1 and the Profibus PA.
A fieldbus terminator is built in and can be implemented via a jumper link.
Cable shields can either be capacitively or directly earthed.
The trunk voltage connecting to the Fieldbus Barrier is monitored for undervoltage (< 16V) and indicated
by an LED. Other LEDs indicate the status of the spurs.
4.1 Power management
As soon as the voltage on the trunk exceeds 16V, the spurs are activated in turn to avoid a high start-
up current. In the event of a short-circuit, the spur in question is de-activated until the short-circuit is
removed.
If several spurs are in a short-circuit condition, the trunk is loaded with a maximum of only one short-
circuit current. This minimises the current consumption of the trunk and the power loss of the Fieldbus
Barrier under all operating conditions.
The total current available across all eight spurs is 160mA. An average current of 20mA is therefore
available to each spur, which is adequate in practice as most fieldbus instruments require less than 20mA
to operate. Individual spurs can supply a continuous current of 40mA, provided the total current budget
of 160mA is not exceeded. This allows a hand-held test device to be connected in parallel with an
instrument, for example, or the connection of an instrument which requires a higher operating current.
On power-up, the spurs are energised in sequence under the control of in internal microprocessor.
Approximately 50mA is available momentarily at each spur to accommodate inrush current.
The 931x-FB Fieldbus Barrier Calculator Tool models the behaviour of the 9312-FB-ST-SS-SP and can be
used to design fieldbus segments; taking into account the individual spur currents, trunk cable length and
power supply characteristics. A single spur short-circuit can also be assumed per segment. Warnings are
displayed if any design parameters are exceeded.
Host
Fieldbus
power
supply
Trunk Ex e
Field
devices
Power Spurs Ex i
Ter inator
Fieldbus BarrierFieldbus Barrier
Zones 1, 2,
12 8 12 8
Figure 3: Functional diagram

6
INM9312-FB-ST-SS-1 Oct 2008 6
1Trunk connections
The Ex e connection terminals for the trunk and the jumper for activating the terminating
resistor are protected by a hinged cover (IP 30).
2Spur connections
Ex i connection terminals for spurs 1 – 8
3Indicator LEDs for spurs 1 – 8
4Indicator LEDs for PWR (power) and ERR (error)
5Bus bar for cable shields with movable terminals
6Ground stud for earthing
7Partition plate; provides required seperation between Ex e and Ex i connection terminals
8Storage position for terminator jumper
5 DEVICE CONSTRUCTION
Figure 4:

7
INM9312-FB-ST-SS-1 Oct 2008 7
6 TRANSPORT, STORAGE AND DISPOSAL
Transport
The product is to be transported in its original carton and handled carefully.
Storage
Storage temperature range: –40°C to +75°C
Store in a dry place in its original packing.
Disposal
Ensure environmentally friendly disposal of all components according to legal regulations.
7 MOUNTING
Do not select a mounting location that requires cable lengths in excess of the maximum permissible
values (see chapter 8.3, Cable lengths).
Refer to Appendix 1 - Technical Data for enclosure dimensions and spacing of mounting holes
8 INSTALLATION
WARNING
Incorrectly installed components!
Explosion protection cannot be guaranteed if the components are incorrectly
installed.
Carry out the installation in strict accordance with the instructions and national
safety and accident prevention regulations (e.g. IEC 60079-14).
Ex
WARNING
Incorrectly installed components!
Explosion protection cannot be guaranteed if the components are incorrectly
installed.
Carry out the installation in strict accordance with the instructions and national
safety and accident prevention regulations (e.g. IEC 60079-14).
Ex

8
INM9312-FB-ST-SS-1 Oct 2008 8
8.1 Examples of fieldbus segment topologies
Fieldbus segment with "daisy chain" structure. The trunk is looped through the Fieldbus Barrier.
Fieldbus segment in which the Fieldbus Barriers are connected to the trunk with junction boxes
(T-connectors).
Fieldbus segment with star structure.
8.2 Proof of intrinsic safety
The spurs comply with FISCO requirements, in accordance with IEC 60079-27.
Fieldbus
power
supply
Host
Host
redundant
Trunk length 1 Trunk length 2 Trunk length 3 Trunk length 4
Trunk
not Ex i
Spurs non Ex i Spur
length
9312 FB
Fieldbus Barrier
9312 FB
Fieldbus Barrier
9312 FB
Fieldbus Barrier
9312 FB
Fieldbus Barrier
12 8 12 8 12 8 12 8
Fieldbus
power
supply
Host
Host
redundant
Trunk length 1 Trunk length 2
Trunk
not Ex i
<= 1m <= 1m
<= 1m
Spurs non Ex i Spur
length
9312 FB
Fieldbus Barrier
9312 FB
Fieldbus Barrier
9312 FB
Fieldbus Barrier
9312 FB
Fieldbus Barrier
12 8 12 8 12 8 12 8
Figure 5:
Figure 6:
Figure 7:
Fieldbus
power
supply
Host
Host
redundant
Trunk length 1 Trunk length 2 Trunk length 3 Trunk length 4
Trunk
not Ex i
Spurs non Ex i Spur
length
9312 FB
Fieldbus Barrier
9312 FB
Fieldbus Barrier
9312 FB
Fieldbus Barrier
9312 FB
Fieldbus Barrier
12 8 12 8 12 8 12 8

9
INM9312-FB-ST-SS-1 Oct 2008 9
8.2.1 Proof of intrinsic safety in accordance with FISCO
A spur is intrinsically safe if:
♦the field device is certified in accordance with FISCO.
♦the conditions regarding cable values as per IEC 60079-27 are adhered to:
Rc 15 –150 ohm/km
Lc 0.4 – 1mH/km
Cc 45 – 200nF/km
Where these requirements are complied with, it is not necessary to consider the inductance and
capacitance of the spur cables.
8.2.2 Proof of intrinsic safety in accordance with the classic "entity concept":
A spur is intrinsically safe if the safe maximum values for the field device and spur connections are
met:
Spur of Field device
Fieldbus Barrier
U
o≤U i
I
o≤I i
P
o≤P i
C
o≥C i+ Ccable
L
o≥L i + Lcable
Where, Ccable and Lcable are the total capacitance and inductance, respectively, of the spur cable, which,
in turn, depends on the cable length.
8.3 Cable lengths for trunk and spurs
IEC 61158–2, Annex B states that the maximum length for all cables per segment, including all trunks
and spurs, must not exceed 1900 m. In addition, the maximum spur length depends on the total number
of field devices per segment, as follows:
In practice, the actual trunk and spur lengths may be shorter because of voltage drops.
For a typical installation, with up to two 9312–FB Fieldbus Barriers per segment, and all spurs connected,
the maximum spur length will be 90m. This applies for spurs connected to field devices that have either
FISCO or Entity certification.
Note: The maximum length of an Ex i spur according to IEC 60079-27 (FISCO) is 60 m. However,
from the viewpoint of the FISCO model, the Ex i spurs of a Fieldbus Barrier are considered as a new
segment (where the maximum segment length = 1000 m). The maximum spur length is therefore 120m,
limited by IEC 61158-2.
Number of all field devices on the segment,
including host(s)
1 ... 12 13 ... 14 15 ... 18 9 ... 24 25 ... 30
Max. spur cable length, 120 m 90 m 60 m 30 m 1 m
assuming1 field device per spur

10
INM9312-FB-ST-SS-1 Oct 2008 10
8.4 Connections
WARNING
Laying intrinsically safe and non-intrinsically safe cables together!
Explosion protection is no longer in force.
Intrinsically safe and non-intrinsically safe cables must be separated in accordance
with IEC 60079-14.
Ex
Foundation fieldbus H1
or Profibus PA
Field devices
Ex i
Ex i
Ex i
Ex i
SPUR 1
S

+
SPUR 2
S

+
SPUR 3
S

+
SPUR 4
S

+
Power Management
S

+
Foundation fieldbus H1
or Profibus PA Trunk
not
Ex i
not
Ex i
T1
T2 T
I
I
I
I
TRUNK IN
S

+
TRUNK OUT
Ex i
Ex i
Ex i
Ex i
SPUR 5
S

+
SPUR 6
S

+
SPUR 7
S

+
SPUR 8
S

+
I
I
I
I
Figure 8: Circuit

11
INM9312-FB-ST-SS-1 Oct 2008 11
Trunk
TRUNK IN and TRUNK OUT (+,–,S) are interconnected in the Fieldbus Barrier.
 Ensure that the fieldbus trunk cable is de-energised before commencing wiring .
 Open enclosure/cover.
 Insert leads in the corresponding terminals:
TRUNK IN: Cable from host / fieldbus power supply
TRUNK OUT: If applicable, cable to the next Fieldbus Barrier
 Secure the terminals using an appropriate tool.
 Close cover/enclosure.
Spurs
Intrinsically safe spur connections can be worked on while power is connected to the Fieldbus Barrier.
Only one field device should be connected per spur connection.
 Open enclosure.
 Insert leads in the corresponding terminals.
 Secure the terminals using an appropriate tool.
 Close enclosure.
WARNING
IP30 cover open on the non-intrinsically safe trunk:
Explosion protection is not in force when the cover is open.
Power to the fieldbus must be de-energised before opening the cover.
If the isolating switch is inside the hazardous area it must be suitably protected.
The fieldbus trunk must be secured against unauthorised activation at this time.
Ex
Figure 9: Trunk and spur connections

12
INM9312-FB-ST-SS-1 Oct 2008 12
8.5 Earthing / Grounding
The 9312-FB-ST-SS-SP Fieldbus Barrier incorporates galvanically isolated safety barriers for the spur
wiring, so an intrinsic safety earth connection is not required.
A number of options for grounding cable screens is available on the 9312-FB-ST-SS-SP barrier, including
‘capacitive’ and direct grounding.
Option 1 - Single point of grounding; trunk and spur shields interconnected
In many installation, the preferred method of grounding is to ground the fieldbus cables 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. Cable connections to
the Fieldbus Barrier should then be as shown above in Figure 10.
Note: In order to maintain a single point of grounding, neither the Fieldbus Barrier module nor the
cable shield earth bar should be connected to an external ground. For the 9312-FB-ST-SS-SP Fieldbus
Barrier, the grounding stud (1) is not connected to the enclosure body. The earth cable (2) is supplied
pre-assembled into the enclosure, but this does not connect the shields of the trunk and spur cables to
ground.
Figure 10: Trunk and spur cable shields to earth bus bar

13
INM9312-FB-ST-SS-1 Oct 2008 13
Option 2 - Local grounding of spur cable shields
If plant or local regulations require that the spur cable shields be grounded at the Fieldbus Barrier, then
the arrangement shown in Figure 11 may be adopted.
With this arrangement, the spur cable shields are connected to local ground via the cable shield busbar.
The trunk cable shields are connected to ground via 4,7μF capacitors that are internally connected
between the ‘S’ terminals of the trunk terminal block and the grounding stud (2).
The connection between the cable shield busbar and local ground (3) can be omitted if the Fieldbus
Barrier is installed into a steel enclosure using mounting screws, as there is electrical continuity between
the grounding stud (2) and the enclosure body.
Capacitive grounding of the spur cables can also be configured by connnecting the spur cable shield to
the ‘S’ terminals of the spur terminal blocks.
Figure 11: Spur cable shields to earth busbar

14
INM9312-FB-ST-SS-1 Oct 2008 14
Option 3 - Multiple points of grounding
In installations where potential equalisation is known to provide a consistent, low impedance ground
plane throughout the plant, the fieldbus cable may be grounded at more than one point.
This is illustrated in Figure 12 where the trunk and spur cable shields are interconnected at the cable
shield busbar (1) and the busbar is connected to local ground (2).
Figure 12: Multiple point grounding

15
INM9312-FB-ST-SS-1 Oct 2008 15
8.6 Fieldbus Terminating
A fieldbus terminator is required at both ends of the trunk.
Spurs are operated without terminating resistors.
Fieldbus Barrier is located at the end of the trunk
In this case, the terminals on the "TRUNK OUT" terminal block are not to be used.
 Remove the factory-provided jumper from its storage position (1).
 Insert the jumper in terminals "1" and "2" on the terminal block (2).
 Close/screw tight the terminals.
 The built-in terminator is activated.
Fieldbus Barrier is not located at the end of the trunk
The terminals on the terminal block are not to be used.
 Ensure the factory-provided jumper is in its storage position (1).
 The built-in terminator is not activated.
Figure 13: - Terminator jumper fitted
Figure 14: - Terminator jumper not required
T
T

16
INM9312-FB-ST-SS-1 Oct 2008 16
9 COMMISSIONING AND OPERATION
Before commissioning
 Test the components for correct operation and installation in accordance with the operating instruc-
tions and other applicable specifications.
 Check that cables and lines are clamped properly.
 Inspect housing for damage.
 Inspect housing for foreign bodies.
 Check whether all unused cable glands and holes are sealed off properly.
 The voltage on the trunk must be at least 16 V DC.
 The voltage to the connected field devices must be at least 9 V DC.
Commissioning
 Observe the national regulations when commissioning.
 Follow the IEC 60079-17 when conducting function inspections.
LED indicators, functional description
PWR (green) ERR (red) S1 – S8 (yellow) Description
OFF – – Voltage on trunk <16V
ON – – Voltage on trunk OK ( >16V )
– OFF OFF Spur open-circuit ( I ≤1mA )
– OFF ON Spur current in range ( 3 – 40mA )
(field device connected)–
– flashing flashing Spur short-circuit
( Current 40 – 50mA )
– ON – Internal fault in Fieldbus Barrier
Figure 15: LED indicators

17
INM9312-FB-ST-SS-1 Oct 2008 17
10 MAINTENANCE
The enclosure may be opened while connected to power.
Intrinsically safe spurs can be worked on while connected to power.
10.1 Regular maintenance work
The type and scope of the checks that must be made are defined in the appropriate national regulations
(e.g. IEC 60079-17) .
 Plan the intervals so that any defects in the equipment which may be anticipated are promptly
detected.
To check as part of the servicing/maintenance schedule:
♦Check that cables and lines are clamped properly.
♦Check tightness of the cable glands.
♦Inspect housing for visible damage.
♦Check the seal between the enclosure and cover (where appropriate).
♦Look for signs of moisture in the enclosure.
♦Check of operation within the published ambient temperature range.
10.2 Repair work
10.3 Cleaning
♦Clean with a damp cloth only, using water or mild, non-abrasive, non-scratching cleaning agents.
♦Never use aggressive cleaning agents or solvents.
WARNING
Danger from energised parts!
Switch off the power to the fieldbus before opening the cover of the trunk
connections.
Secure the fieldbus against unauthorised activation.
Ex
WARNING
Danger due to improper maintenance/repairs!
Explosion protection is not guaranteed any longer.
Repairs to the device must only be performed by MTL
or an authorised representative
Ex

18
INM9312-FB-ST-SS-1 Oct 2008 18
APPENDIX 1 - TECHNICAL DATA
Explosion protection
Fieldbus Barrier II 2 (1) G D Ex mb e ib [ia] IIC/IIB T4
module BVS 06 ATEX E 135X
Ta = –40°C to +75°C
Spurs “FISCO“ according to IEC 60079-27
suitable enclosure neccessary
Fieldbus Barrier II 2 (1) G EEx mb ed ib [ia] IIC T4
enclosure: PTB 01 ATEX 1001
Ta = –40°C to +70°C
Spurs “FISCO“ according to IEC 60079-27
Installation in Zones 1 and 2, Zones 21 and 22 (dust), with suitable enclosure
Safety data (CENELEC)
each spur
FISCO (IEC 60079-27)
Max. voltage Uo15.7V
Max. current Io245mA
Max. power Po960mW
Max. connectable capacitance
Cofor IIC / IIB 476nF / 2878nF
Max. connectable inductance
Cofor IIC / IIB 0.58mH / 2.9mH
Max. internal capacitance Ci1.1nF
Max. internal inductance Li~ 0mH
Insulation voltage Um253V
Power supply powered from the trunk
Galvanic isolation
(to EN 50020)
Ex i spurs to Ex e trunk 1.5kV (test voltage)
Ex i spur to Ex i spur no isolation
Data transmission
between trunk and spurs passive, no repeater function
Trunk,
non intrinsically safe / Ex e
Connections 2 trunk connections (in, out), internally interconnected
Voltage range 16 – 32V
Low voltage monitoring U < 16V, spurs de-energized
Max. DC current at 16 V at 24V at 32V
0 mA each spur 32mA 26mA 23mA
20 mA each spur 223mA 147mA 112mA
7 spurs @ 20 mA,
1 spur in short-circuit 265mA 172mA 132mA
short-circuit all spurs < 90mA < 70mA < 60mA
Max. power dissipation 1.8W
Indication LED green “PWR“
(U ≥16V on trunk)