SH 8387-3S EN
Translation of original instructions

TROVIS SAFE 3731-3 Electropneumatic Ex d Positioner
Communication: HART®

Edition July 2020

Definition of signal words! DANGER
Hazardous situations which, if not avoided,
will result in death or serious injury! WARNING
Hazardous situations which, if not avoided,
could result in death or serious injury

2! NOTICE
Property damage message or malfunction
Note
Additional information
Tip
Recommended action

SH 8387-3S EN

Purpose of this manual
The Safety Manual SH 8387-3S contains information relevant for the use of the TROVISSAFE 3731-3S Positioner in safety-instrumented systems according to IEC 61508 andIEC 61511. The safety manual is intended for planners, constructors and operators of safetyinstrumented systems.
! NOTICE
Risk of malfunction due to incorrect mounting, connection or start-up of the positioner.
Î Refer to the Mounting and Operating Instructions EB 8387-3S on how to mount thepositioner, perform the electric and pneumatic connections as well as start up the
positioner.
Î Observe the warnings and safety instructions written in the Mounting and Operating
Instructions EB 8387-3S.
Further documentation
The documents listed below contain descriptions of the start-up, functioning and operation of
the positioner. You can download these documents from the SAMSON website.
TROVIS SAFE 3731-3 Positioner
u T 8387-3S: Data sheet
u EB 8387-3S: Mounting and operating instructions
u KH 8384-3: Configuration manual
EXPERTplus diagnostics
u T 8389S:
Data sheet
u EB 8389S:
Operating instructions

Note
In addition to the positioner documentation, observe the documentation for the pneumatic
actuator, valve and other valve accessories.

SH 8387-3S EN

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4SH 8387-3S EN

Contents

1
1.1
1.2
1.3
1.4

Scope............................................................................................................6
General.........................................................................................................6
Use in safety-instrumented systems...................................................................6
Versions and ordering data.............................................................................6
Attachment.....................................................................................................62

Technical data (excerpt from EB 8387-3S)........................................................7

3
3.1
3.2

Safety-related functions..................................................................................8
Fail-safe action...............................................................................................8
Protection against unauthorized changes to the configuration.............................94

Mounting, connection and start-up..................................................................9

5
5.1
5.2
5.3

Required conditions........................................................................................9
Selection........................................................................................................9
Mechanical and pneumatic installation...........................................................11
Electrical installation......................................................................................12

6
6.1
6.2

Proof testing (periodic)..................................................................................12
Visual inspection to avoid systematic failure....................................................13
Function testing.............................................................................................13

7

Maintenance and repair...............................................................................15

8

Safety-related data and certificates...............................................................16

SH 8387-3S EN

5Scope1 Scope
1.1 General
The TROVIS SAFE 3731-3 Electropneumatic Ex d Positioner is a single-acting positioner for
mounting on pneumatic rotary and linear actuators with spring-return mechanism. The positioner is used to position control valves.
The positioner is ready configured for 'On/off valve' type of application. In this type of
application, it is used to shut off or open on/off valves on demand. The positioner is used toposition control valves when the 'Control valve' is selected as the type of application. The
type of application does not have any effect on the safety-instrumented function.

1.2 Use in safety-instrumented systems
Observing the requirements of IEC 61508, the systematic capability of the pilot valve for
emergency venting as a component in safety-instrumented systems is given.
Use of the positioner is possible on observing the requirements of IEC 61511 and the required hardware fault tolerance in safety-instrumented systems up to SIL 2 (single device/
HFT = 0) and SIL 3 (redundant configuration/HFT = 1).
The Ex d positioner is regarded as a type A device according to IEC 61508-2 in view of its
safety functions.

1.3 Versions and ordering data
All versions of the TROVIS SAFE 3731-3 Positioner are suitable for use in safety-instrumented
systems.

1.4 Attachment
The positioner is suitable for the following types of attachment in combination with various
mounting parts:− Direct attachment to SAMSON Type 3277 Linear Actuators− Attachment to linear actuators according to IEC 60534-6 (NAMUR)− Attachment to SAMSON Type 3510 Micro-flow Valve− Attachment to rotary actuators according to VDI/VDE 3845

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SH 8387-3S EN

Technical data (excerpt from EB 8387-3S)

2 Technical data (excerpt from EB 8387-3S)
TROVIS SAFE 3731-3 · Technical data in test certificates additionally apply to explosion-protected devices.
Action on fault detection

TROVIS SAFE 3731-3xxxxxx000x1x00: Emergency shutdown at 0 mA
TROVIS SAFE 3731-3xxxxxx100x1x00: Emergency shutdown at <3.8 mA

Minimum current

3.6 mA for display · Load impedance <9 V corresponding to 450 Ω at 20 mA

SupplySupply air

TROVIS SAFE 3731-321, TROVIS SAFE 3731-327: 1.4 to 7 bar (20 to 105 psi),
TROVIS SAFE 3731-323: 1.4 to 6 bar (20 to 90 psi)

Air quality acc. toISO 8573-1(2004 edition)

Maximum particle size and density: Class 4 · Oil content: Class 3
Moisture and water: Class 3 · Pressure dew point at least 10 K below the lowest
ambient temperature to be expected

Signal pressure (output)
Characteristic

0 bar up to the supply pressure
Can be limited to 1.4 bar/2.4 bar/3.7 bar ± 0.2 bar by software
Linear/Equal percentage/Reverse equal percentage
Butterfly valve, rotary plug valve or segmented ball valve: Linear/equal percentage
User-defined: adjustable over operating software and communication

Deviation<1 %Hysteresis<0.3 %

Sensitivity<0.1 %

Transit time

Exhaust and supply adjustable separately up to 240 s by software

Direction of action

Reversible

Air
Steady state
consumption

Independent of supply air approx. < 110 ln/h

Air output
capacity

Actuator (supply)

At Δp = 6 bar: 8.5 mn³/h · At Δp = 1.4 bar: 3.0 mn³/h · KVmax(20 °C) = 0.09

Actuator (exhaust) At Δp = 6 bar: 14.0 mn³/h · At Δp = 1.4 bar: 4.5 mn³/h · KVmax(20 °C) = 0.15

Permissible ambient temperature

Use in safety-instrumented
systems (SIL)–40 to +80 °C, the limits in the test certificate additionally apply.
Observing the requirements of IEC 61508, the systematic capability of the pilot
valve for emergency venting as a component in safety-instrumented systems isgiven.
Use is possible on observing the requirements of IEC 61511 and the required hardware fault tolerance in safety-instrumented systems up to SIL 2 (single device/
HFT = 0) and SIL 3 (redundant configuration/HFT = 1).

Communication
Local communication

SAMSON SSP interface and serial interface adapter

Software requirements (SSP)TROVIS-VIEW with database module TROVIS SAFE 3731-3

HART® communication

HART® field communication protocol
Impedance in HART® frequency range: Receiving approx. 455 Ω · Sending approx.
185 Ω

SH 8387-3S EN

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Safety-related functions

For handheld

communicator
Softwarerequirements(HART®)For computer

Device description for TROVIS SAFE 3731-3
DTM file certified according to specification 1.2, suitable for integrating the device
into frame applications that support the use of FDT/DTM (e.g. PACTware); Integration into AMS™ Suite available

3 Safety-related functions
TROVIS SAFE 3731-3xxxxxx000x1x00: Emergency shutdown at 0 mA
In automatic mode, the PD controller (3) compares the valve position to the DC control signal
from 4 to 20 mA issued by the microcontroller. In case of a system deviation, the activationof the i/p converter is changed so that the actuator (1) is either vented or supplied with air.
Fail-safe action is triggered and the actuator is vented when no signal (0 mA) is applied toterminals for 4 to 20 mA, HART® and, as a result, to the i/p converter.
TROVIS SAFE 3731-3xxxxxx100x1x00: Emergency shutdown at <3.8 mA
In automatic mode, the PD controller (3) compares the valve position to the DC control signal
from 4 to 20 mA issued by the microcontroller. In case of a system deviation, the activationof the i/p converter is changed so that the actuator (1) is either vented or supplied with air.
Fail-safe action is triggered when a signal smaller or equal to the shutdown signal (<3.8 mA)
is applied to terminals for 4 to 20 mA, HART® and, as a result, to the i/p converter.

3.1 Fail-safe action
Fail-safe action is triggered by the i/p converter upon supply air failure (TROVIS SAFE
3731-3xxxxxx000x1x00) or when the shutdown signal falls below a certain value(<3.8 mA, TROVIS SAFE 3731-3xxxxxx100x1x00). The positioner fully discharges its pneumatic output to the atmosphere, causing the pneumatic actuator to be vented. As a result, thevalve moves to the fail-safe position. The fail-safe position depends on how the springs arearranged in the pneumatic actuator (air-to-close or air-to-open).
When the air supply fails, all positioner functions, except for open/closed-loop control, remain active (including diagnostics and communication).

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SH 8387-3S EN

Mounting, connection and start-up

Note
The pneumatic output of the positioner can also be vented to the atmosphere over the software, e.g. by entering a suitable set point. This procedure is not a safety-instrumented function.

3.2 Protection against unauthorized changes to the configuration
A change to the configuration cannot affect the safety function nor cause it to be deactivated.

4 Mounting, connection and start-up
Refer to Mounting and Operating Instructions u EB 8387-3S on how to mount, perform theelectric and pneumatic connections as well as start up the positioner.
Only use the specified original mounting parts and accessories.

5 Required conditions! WARNING
Risk of malfunction due to incorrect selection or wrong installation and operating conditions.
Î Only use control valves in safety-instrumented systems if the necessary conditions in theplant are fulfilled. The same applies to the mounted positioner.

5.1 Selection
Î The required transit times of the control valve are observed.
The transit times to be implemented are determined by the process engineering requirements.
Tip
The minimum OPEN and CLOSE transit times can be read in Codes 40 and 41 after the
positioner has been initialized.
Î The positioner is suitable for the prevailing ambient temperature.

SH 8387-3S EN

9Mounting, connection and start-up

Signal:(polarity insensitive)
Options:

4...20 mA
HART®

Two-wire transmitter supply unit forthe position transmitter

A B C

Binary output
PLC DC/AC

A B C

A
+ _
11...35 V DC

Forced venting

Binary input
Voltage input (polarity insensitive)

A B C

A B C

L/+ N/_
0...40 V DC
0...28 V AC

0...24 V DC

Binary output
Switching amplifier EN 60947-5-6

Binary input
Contact input for an external contact

A B C

+

A B C

_

Fig. 1: Electrical connection

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SH 8387-3S EN

Required conditions

Versions

Temperature rangeAll–40 to +80 °C

The temperature limits for the explosion-protected devices may be further restricted by the limits specified in the test certificates.

Î The temperature limits are observed.

5.2 Mechanical and pneumatic installation
Î The positioner is mounted properly as described in the mounting and operating instructions and connected to the air supply.
Tip
Error codes 50 to 58 indicate incorrect attachment. For safety-instrumented systems, werecommend assigning the 'Maintenance alarm' status to these errors to quickly recognize
them when they occur (indicated by on the display).
Î The supply pressure does not exceed the maximum limit specified below.
–

TROVIS SAFE 3731-321 and 3731-327: 7 bar–

TROVIS SAFE 3731-323: 6 bar

Î The pneumatic air supply meets the instrument air specifications.
Particle size and quantity

Oil content

Moisture and water

Class 4

Class 3

Class 3< 5 µm and 1000/m³< 1 mg/m³

Pressure dew point: at least 10 K below thelowest ambient temperature to be expectedTip
We recommend installing a supply pressure regulator/filter upstream of the device. For
example, the SAMSON Type 4708 Supply Pressure Regulator with 5 µm filter cartridge
can be used.
Î The supply air line has a minimum inside diameter of 4 mm.
Select the cross section and length of the line to ensure that the supply pressure at thepositioner on supplying air to the actuator does not fall below the minimum limit.
Î The positioner is mounted as prescribed.
Î The vent opening at the back of the positioner remains open when the positioner is installed on site.

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Proof testing (periodic)

5.3 Electrical installation
Î The positioner is connected to the electric power supply properly as described in themounting and operating instructions.
Î Only cables whose outside diameters are suitable for the cable glands are used.
Î When the positioner is connected according to the type of protection Ex d, cable entries
or conduit systems are used that comply with EN 60079-1 Explosive Atmospheres –Part 1: Equipment Protection by Flameproof Enclosures "d", Clauses 13.1 and 13.2 andfor which a separate test certificate is available.
Î When the positioner is connected according to the type of protection Ex e, cable entries
and blanking plugs are used, which are certified according to type of protection Ex e
(ATEX) and have a separate test certificate.
Î The cable glands and cover screws are fastened tightly to ensure that the degree of protection is met.
Î The installation requirements for the applicable explosion protection measures are observed.
Î The special conditions specified in the explosion protection certificates are observed.

6 Proof testing (periodic)
The proof test interval and the extent of testing lie within the operator's responsibility. The
operator must draw up a test plan, in which the proof tests and the interval between them
are specified. We recommend summarizing the requirements of the proof test in a checklist.
! WARNING
Risk of dangerous failure due to malfunction in the event of emergency (actuator is notvented or the valve does not move to the fail-safe position).
Î Only use devices in safety-instrumented systems that have passed the proof test according
to the test plan drawn up by the operator.
Regularly check the safety-instrumented function of the entire SIS loop. The test intervals are
determined, for example on calculating each single SIS loop in a plant (PFDavg).

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SH 8387-3S EN

Proof testing (periodic)

6.1 Visual inspection to avoid systematic failure
To avoid systematic failure, inspect the positioner regularly. The frequency and the scope of
the inspection lie within the operator's responsibility. Take application-specific influences into
account, such as:− Dirt blocking the pneumatic connections− Corrosion (destruction primarily of metals due to chemical and physical processes)− Material fatigue− Aging (damage caused to organic materials, e.g. plastics or elastomers, by exposure tolight and heat)− Chemical attack (organic materials, e.g. plastics or elastomer, which swell, leach out or
decompose due to exposure to chemicals)! NOTICE
Risk of malfunction due to the use of unauthorized parts.
Î Only use original parts to replace worn parts.

6.2 Function testing
Regularly check the safety function according to the test plan drawn up by the operator.
Note
Record any positioner faults and e-mail (aftersalesservice@samsongroup.com) them to
SAMSON.
TROVIS SAFE 3731-3xxxxxx000x1x00: emergency venting by applying a 0 mA signal to
the terminals for 4 to 20 mA, HART®
1. Supply the positioner with air within the permissible supply pressure range (max. 7 barfor TROVIS SAFE 3731-321 and TROVIS SAFE 3731-327 or 6 bar for TROVISSAFE 3731-323) which allows the valve to move to the maximum travel/angle of rotation.
2. Connect an electric input signal >3.6 mA to the positioner (terminals for 4 to 20 mA,
HART®).
3. Switch the positioner to automatic mode (if it has not already been done).

SH 8387-3S EN

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Proof testing (periodic)

4. Set the input signal (terminals for 4 to 20 mA signal, HART®) over a local current sourceor over the control system in such a way that the valve moves to the operating position.
Check whether the valve moves to this position.
Tip
The travel/angle of rotation in automatic mode can be read at the positioner in Code 0.
5. Set the electric input signal to 0 mA or disconnect it. This must cause the valve to move toits fail-safe position.
6. Check whether the actuator is fully vented within the demanded time.
Tip
Connect a pressure gauge to check that the actuator has completely vented.
TROVIS SAFE 3731-3xxxxxx100x1x00: emergency venting by applying a <3.8 mA signal
to the terminals for 4 to 20 mA, HART®
1. Supply the positioner with air within the permissible supply pressure range (max. 7 barfor TROVIS SAFE 3731-321 and TROVIS SAFE 3731-327 or 6 bar for TROVISSAFE 3731-323) which allows the valve to move to the maximum travel/angle of rotation.
2. Connect an electric input signal ≥3.8 mA to the positioner (terminals for 4 to 20 mA,
HART®).
3. Switch the positioner to automatic mode (if it has not already been done).
4. Set the input signal (terminals for 4 to 20 mA signal, HART®) over a local current sourceor over the control system in such a way that the valve moves to the operating position.
Check whether the valve moves to this position.
Tip
The travel/angle of rotation in automatic mode can be read at the positioner in Code 0.
5. Set the electric input signal to <3.8 mA. This must cause the valve to move to its fail-safe
position.
6. Check whether the actuator is fully vented within the demanded time.

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SH 8387-3S EN

Maintenance and repair

Tip
Connect a pressure gauge to check that the actuator has completely vented.
Proof test
A full stroke test must be performed as the proof test. The following value can be used for
Proof Test Coverage to calculate PFDavg:
PTC (Proof Test Coverage) = 92 % for a proof test

7 Maintenance and repair
Only perform the work on the positioner described in u EB 8387-3S.
! NOTICE
Safety function impaired due to incorrect repair.
Î Only allow trained staff to perform service and repair work.
For devices operated in the low demand mode, a useful lifetime of 11 years (plus 1.5 years
storage time) is confirmed by TÜV Rheinland® from the date of manufacture while taking into
account the specific conditions of use specified in the Safety Manual and the Mounting andOperating Instructions.
The results of the proof test must be assessed and the maintenance scheduled based on it. In
particular, after changes (e.g. signs of aging in elastomers, changed switching times or leakage etc.), it is essential that the manufacturer performs maintenance or repair work on thedevice.
MTC (Maintenance Coverage) > 99 %SH 8387-3S EN

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Safety-related data and certificates

8 Safety-related data and certificates
PSTC (Partial Stroke Test Coverage)

68 %PTC (Proof Test Coverage)

92 %MTC (Maintenance Coverage)>99 %Further safety-related data are listed in the following certificate.

16

SH 8387-3S EN

SH 8387-3S EN

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SH 8387-3S EN

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SAMSON AKTIENGESELLSCHAFT
Weismüllerstraße 3 · 60314 Frankfurt am Main, Germany
Phone: +49 69 4009-0 · Fax: +49 69 4009-1507
samson@samsongroup.com · www.samsongroup.com

2020-08-24 · English

SH 8387-3S EN