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

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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

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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

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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.

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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

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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:

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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