Siemens SITRANS P. Operating Instructions (2019)

Functional Safety

10.1 Safety concept

See also

General functional safety (http://www.siemens.com/safety )

Functional safety in process instrumentation (http://www.siemens.com/SIL )

10.1.3

Safety function

The safety function of the device is the pressure measurement or the measurement of certain

process values which can be calculated from the pressure value.

The 4 to 20 mA analog output can be used as part of a safety instrumented function (SIF).

Ensure that you have only connected one device per channel and that the current output is

activated.

Besides the application-specific measuring errors under default reference conditions, an

additional safety accuracy of ± 2% of the maximum measuring range must be added:

Total tolerance (safety function) = ± [application-specific measurement error + 2 % safety

accuracy].

Example

A silo is to be securely monitored to check that the level does not exceed 10 meters.

Application-specific measurement error: 0.1%

Safety accuracy: 2.0%

Total tolerance: 2.1%

2.1% of 10 meters is 21 centimeters. When process monitoring is set to 9.79 meters, safe

shutdown is guaranteed even in the event of a random individual error within the safety

accuracy.

Note

Use of remote seals

If remote seals are used, the application-specific measurement error is the product of the

pressure transmitter and remote seal measurement errors.

Safety allowance

The diagnostics function reacts within 2 seconds after detection of an error.

Note

For use outside the standard reference conditions, contact Siemens to define an additional

safety accuracy.

See also

Remote seals and primary element for devices with functional safety (Page 41)

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Safety-instrumented system in single-channel operation (SIL 2)

Transmitter

Automation system

Final controlling

Figure 10-1

Safety-instrumented system in single-channel operation

The combination of pressure transmitter, automation system and final controlling element

forms a safety-instrumented system that performs fail-safe behavior. The focus of this

description is on the pressure transmitter. For information on requirements for the automation

system or final controlling element, please refer to the corresponding standards.

The pressure transmitter generates a process-related measured value that is transferred to the

automation system. The automation system monitors this measured value. If the measured

value violates the high or low limit, the automation system generates a shutdown signal for the

connected final controlling element, which switches the corresponding valve to the specified

safety position.

Only one SITRANS P device is required for single-channel operation for SIL 2.

Safety-instrumented system in multi-channel operation (SIL 3)

Transmitter

Automation system

Final controlling elements

Figure 10-2

Safety-instrumented system in multi-channel operation

The combination of transmitter, automation system and final controlling element forms a safety-

instrumented system that performs a safety function. The emphasis of this description is on the

transmitter. For information on requirements for the automation system or final controlling

element, please refer to the corresponding standards.

The transmitter generates process-related measured values that are transferred to the

automation system. The automation system monitors these measured values. In the event of

a fault, the automation system generates shutdown signals for connected final controlling

elements that set the associated valve to the defined safety position. Faults are:

● Violations of the preset high or low limits

● Deviations between the two measured values

The automation system program must monitor the measured values of both SITRANS

P devices. As soon as the measured values differ by e.g. 2% or more, the system must be

brought into the safe state and the fault must be located.

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10.1 Safety concept

Two SITRANS P devices are required for multi-channel operation for SIL 3. Operation with one

device is not permitted.

Note

Switching-off of system at high monitoring accuracy

The two transmitters are connected to the process at different positions. Actual differences in

pressure ≥ the total tolerance (safety function) can occur when the process is started up or if

there are other pressure variations. A difference in pressure ≥ the total tolerance (safety

function) will shut down the system.

● Match the monitoring accuracy of the automation system to the process.

● Mount the two transmitters exposed to equal conditions.

10.1.3.1

Device states

The following table provides a definition of the states of the device:

Device state

Description

Error class

Normal mode (4-20 mA)

The safe current output outputs

the measured value within the

defined safety accuracy.

Detected failure (safe state)

The safe current output is

(λ_DD) Rate of dangerous detec-

ted errors

≤ 3.6 mA or > 21.5 mA (specified

as failure signal).

Dangerous state

A dangerous state exists when a

(λ_DU) Rate of dangerous undetec-

current output is in the range

ted errors

4-20 mA and deviates from the

correct process value by more

than the specified safety accura-

cy (Page 160) for more than 2

seconds.

10.1.3.2

Safety characteristic values

You can find the safety characteristic values in the SIL Declaration of Conformity.

Note

Useful lifetime

Constant failure rates are assumed for the calculation of PFD/SFF. This assumption is valid for

environmental conditions that are typical for an industrial environment, corresponding to IEC

60654-1 class C (weatherproof locations) with an average long-term temperature of 40°C. After

14 years, however, the failure rates may increase.

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10.1 Safety concept

10.1.4

Operating modes of the device

The device can be operated as follows:

● "Functional Safety disabled" is used for operation in non-safety-related applications.

● "Functional Safety enabled" is used for operation in safety-related applications.

See also

Enabling Functional Safety (Page 166)

10.1.5

Device mode

When Functional Safety is disabled, the following device modes are displayed via the display

or remote operation:

Device mode

Display

Description

Current output val-

Safe current output

Functional Safety

STD

Used for operation

Operating signal

disabled

in non-safety-rela-

(4 to 20 mA)

ted applications.

The safety-related

parameters of the

device are set.

FUNCT

The safety-relevant

parameters and the

safety function are

validated.

Out of service, non-

O/S

The device is out of

Failure signal

safe mode

service (e.g. a firm-

(≤ 3.6 mA or >

ware update is run-

21.5 mA)

ning)

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10.1 Safety concept

When Functional Safety is enabled, the following device modes are displayed via the display

or remote operation:

Device mode

Display

Description

Current output val-

Safe current output

Functional Safety

SAFE

Ensures safe meas-

Operating signal

Yes

enabled

urement output at

(4 to 20 mA)

the current output.

Safety-related error

ERROR

The system has de-

Failure signal

Yes

tected a safety-criti-

(≤ 3.6 mA or >

cal error in "Func-

21.5 mA)

tional Safety ena-

bled" device mode.

The errors are lis-

ted in the error list

of the device. Once

the errors have

been eliminated,

the device can only

be put back into

safe operation by

performing the

safety validation.

See also

Active device mode [28] (Page 140)

Safety-related parameters (Page 165)

Enabling Functional Safety (Page 166)

10.1.5.1

Validation

In "Functional Safety disabled" device mode, you have the option of making the following

validations before you enable Functional Safety:

● Validation of safety-related parameters.

This validation ensures that all safety-related parameters are correctly transferred to the

device.

● Validation of the safety function (function test).

See also

Enabling Functional Safety (Page 166)

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10.1.5.2

Safety-related parameters

The following parameters are the safety-related parameters of the device:

Parameter ID

Parameter name on

Meaning

the display

PV SELECT

Pressure is the primary variable. The parameter cannot be

changed.

DAMPING

Damping value [04] (Page 110)

UPPER RANGE

Set upper range value parameter [03] (Page 108)

LOWER RANGE

Set lower range value parameter [02] (Page 108)

APPLICATION

Application [05] (Page 110)

OVERLD BEHAV

Overload behavior [36] (Page 145)

SATURAT HIGH

Upper saturation limit (Page 126)

To set these parameters, change the device mode to "Functional Safety disabled".

10.1.5.3

Device mode "Functional Safety enabled"

In "Functional Safety enabled" device mode, an internal diagnostics process of the device

performs the following safety-related checks:

● Sensor breakage monitoring

● Continuous testing of execution and logic behavior of CPU, analog-to-digital converter and

memory

● Temperature monitoring

● Pressure monitoring, depending on the setting of the Overload behavior [36] (Page 145)

parameter.

● Integrity of safety-related parameters

● Plausibility check of current output

When a safety-related critical error is detected in the device, the current output signal

corresponds to the fault current (≤ 3.55 mA) and is independent of the settings of the following

parameters:

Select fault current [10] (Page 124),

Lower fault current [11] (Page 124),

Upper fault current [12] (Page 125),

Lower saturation limit [13] (Page 125),

Note

As long as the device is in the "Functional Safety enabled" device mode, all parameters are

protected against changes.

● To change the parameters, disable Functional Safety.

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10.2 Enabling Functional Safety

Note

Before you enable Functional Safety, follow these steps:

● Setting safety-relevant parameters

● Setting the zero point (Page 119)

● Sensor calibration (Page 151)

● Digital-to-analog converter trim (DAC trim) (Page 152)

The items listed above are tested with the function test (Page 164) of the Functional Safety.

10.2

Enabling Functional Safety

You enable or disable Functional Safety with the "Functional Safety" wizard.

The wizard is available via the device with a display and via remote operation.

For a device without display, enable Functional Safety via remote operation.

You have the following options for enabling Functional Safety:

1. Enable Functional Safety after validation of safety-related parameters and safety function

(recommended).

2. Enabling Functional Safety after validation of safety-related parameters and without

validation of safety function (recommended).

3. Enable Functional Safety without validation.

See also

Validation (Page 164)

Acknowledging safety-related errors (Page 174)

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10.2 Enabling Functional Safety

10.2.1

Enabling Functional Safety over device with display

Requirement

● You have checked the settings of the safety-related parameters.

Safety-related parameters (Page 165)

Note

The main line of the display has a measured value display with a maximum of five digits.

● To completely display the measured values for upper range value [S3] and lower range

value [S4] by means of the maximum five digits available, set the pressure units

(Page 107) correspondingly.

● You have selected one of the following characteristic curves using the "Application"

parameter [05]:

- Linear, proportional to pressure (PRESS).

- Linear, proportional to level (LEVEL).

- Proportional to flow rate, two-step linear up to the application point (VSLN2 or MSLN2).

● You have enabled the "User PIN" parameter [27].

The user PIN you use is not the preset user PIN (2457).

Procedure

1. Navigate to the parameter view.

Navigating in the views (Page 76)

2. Select the parameter "Functional Safety" [29].

3. To start the wizard, enter the user PIN if needed.

4. Use the

button to confirm.

The display test runs automatically.

5. Check that the numbers, texts and symbols are displayed correctly.

6. Once the display test is complete, start the validation of the safety-related parameters and

the safety function.

When you select "ENABL", you enable Functional Safety directly without validation of the

safety-related parameters and the safety function.

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10.2 Enabling Functional Safety

Validating safety-related parameters

1. Select "VALID".

2. Use the

button to confirm.

3. Navigate to the safety-related parameters with the

button.

To correct the safety-related parameters, exit the wizard with the

button. Use the

button to confirm.

Note

Write protection via user PIN is automatically enabled 10 minutes after the last button

operation. The wizard therefore aborts and the validation of the safety-related parameters

is lost.

● To start the wizard again, enter the user PIN.

4. To complete validation of the safety-related parameters, confirm with YES.

5. To validate the safety function, start the function test with "START".

When you select "SKIP", you skip the function test and enable Functional Safety directly

without validation of the safety function.

Validate safety function

1. Check the correct execution of the safety function in which the device is used.

2. In the parameter view, select the "Functional Safety" parameter [29].

3. To continue with the wizard, enter the user PIN if needed.

4. Select "START".

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10.2 Enabling Functional Safety

5. Use the

button to confirm.

6. When you have successfully validated the safety function, restart the wizard and select

"PASSD".

The message "SAFETY MODE ON" (Functional Safety enabled) appears.

Result

The device is in the "Functional Safety enabled" device mode.

Figure 10-3

Parameter view

● The "SIL" symbol is displayed.

● The "DSABL" command appears (Disable Functional Safety).

● All parameters are protected against changes.

● When a safety-related error is detected on the device, the device changes to "Safety critical

error" device mode (Page 174).

See also

Troubleshooting (Page 197)

Diagnostic messages (Page 192)

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10.2 Enabling Functional Safety

10.2.2

Enabling Functional Safety over remote operation

Requirement

● You have documented the device identification:

- During installation, you have read and documented the product name and the serial

number on the nameplate of the device.

- You have defined and documented a long tag (Page 146).

● You have checked the settings of the safety-related parameters.

Safety-related parameters (Page 165)

● You have selected one of the following characteristic curves using the "Application"

parameter [05]:

- Linear, proportional to pressure

- Linear, proportional to level

- Volume flow: two step linear, square root.

- Mass flow: two step linear, square root.

● You have enabled the "User PIN" parameter [27].

The user PIN you use is not the preset user PIN (2457).

Procedure

1. Select the menu command "Functional Safety".

2. Enter the user PIN.

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10.2 Enabling Functional Safety

3. Validate the following settings:

- Identification data of your device: Long tag, product name, serial number.

- Settings of the safety-related parameters

To change the settings, exit the wizard with "Cancel".

4. Write down the fingerprint.

Whenever you start the validation, the device generates a fingerprint. By comparing the

fingerprint, you determine whether or not the device and the safety-related parameters have

changed erroneously during activation of the functional safety.

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10.2 Enabling Functional Safety

3. Enter the user PIN.

4. Validate the identification data of your device.

5. Check that the displayed fingerprint matches the fingerprint you have written down.

6. Confirm the successful function test.

Result

The device is in the "Functional Safety enabled" device mode.

● All parameters are protected against changes.

● When a safety-related error is detected on the device, the device changes to "Safety critical

error" device mode (Page 174).

Note

The system shows unexpected data or behaves differently than described in this procedure.

● Repeat the entire procedure.

See also

Diagnostic messages (Page 192)

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10.3 Acknowledging safety-related errors

10.3

Acknowledging safety-related errors

10.3.1

"Safety critical error" device mode

When a safety-related error is detected on the device, the current output signal corresponds to

the fault current and the diagnostic message is displayed.

Figure 10-4

Example: Diagnostic message for overview

Acknowledge the safety-related error with the "Functional Safety" parameter [29] via local

operation or via the menu command "Functional Safety" through remote operation. (Page 175)

The device then restarts and returns to the "Functional Safety disabled" device mode.

Note

The system shows unexpected data or behaves differently than described in this procedure.

● Repeat the entire procedure.

Note

Damaged device

● Replace the device.

See also

Select fault current [10] (Page 124)

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10.4 Disabling Functional Safety over device with display

4. To acknowledge the safety-related error, click on "Acknowledge".

The device restarts automatically.

5. Validate the identification data of your device again: Long tag, product name and serial

number.

Result

● The safety-related error is acknowledged.

● The device returns to the "Functional Safety disabled" device mode.

Note

The system shows unexpected data or behaves differently than described in this procedure.

● Repeat the entire procedure.

10.4

Disabling Functional Safety over device with display

Requirement

The device is in the "Functional Safety enabled" device mode.

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10.5 Disabling Functional Safety over remote operation

Procedure

1. Navigate to the parameter view.

Navigating in the views (Page 76)

2. Select the parameter "Functional Safety" [29].

3. Enter the user PIN.

The wizard starts.

4. Select YES immediately and confirm wit the

button.

Result

The device switches to "Functional Safety disabled" device mode.

● The "SIL" symbol is displayed.

● The "ENABL" command appears (Enable Functional Safety mode).

Note

If Functional Safety remains enabled, repeat the procedure described above without any

interruptions.

10.5

Disabling Functional Safety over remote operation

Requirement

The device is in the "Functional Safety enabled" device mode.

Procedure

1. Select the menu command "Functional Safety".

2. Enter the user PIN.

3. Validate the identification data of your device: Long tag, product name and serial number.

4. Confirm with "Ok" that you want to disable Functional Safety.

5. Validate the identification data of your device again: Long tag, product name and serial

number.

6. Confirm with "OK".

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10.6 Proof test

Result

The device is in the "Functional Safety disabled" device mode.

Note

The system shows unexpected data or behaves differently than described in this procedure.

● Repeat the entire procedure.

10.6

Proof test

Proof tests can detect errors in the device that are not detected by the integrated diagnostics

of the device.

Proof tests performed at regular intervals uncover undetected errors that can otherwise cause

safety-related functions to function not as intended.

The interval between two proof tests is dependent on the safety-related system, based on the

combined calculations of failure rates for the system.

10.6.1

Intervals and rules for proof test

To ensure reliable operation of the safety function, perform the following proof tests at the

following intervals:

All devices

Read the information on maintenance intervals and checking the seals and cable glands in the

section Maintenance and repair work (Page 182).

Absolute pressure devices

Set the zero point every 5 years for the following variants:

Measuring cell

Absolute pressure from the rela-

Absolute pressure from the dif-

tive pressure/Absolute pressure

ferential pressure series

with front-flush diaphragm

250 mbar a/25 kPa a/100 H₂O

7MF0.2. - .F ... -

7MF0.3. - .G ... -

1300 mbar a/130 kPa a/525 H₂O

7MF0.2. - .L ... -

7MF0.3. - .L ... -

5000 mbar a/500 kPa a/72.5 psi a

7MF0.2. - .P ... -

7MF0.3. - .P ... -

30 bar a/3 MPa a/435 psi a

7MF0.2. - .R ... -

7MF0.3. - .R ... -

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10.7 Repair and service

You can find information on how to set the zero point for absolute pressure in section Adjusting

zero point (absolute pressure) (Page 121)

Note

To set the zero point, first disable Functional Safety.

10.6.2

Documenting a proof test

Documentation of the results of the proof test must be part of the safety management system

of the installation. Errors that are of critical importance for Functional Safety must be reported

to Siemens Technical Support.

10.7

Repair and service

NOTICE

Repair and service

Repair and service work may only be performed by personnel authorized by Siemens.

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Service and maintenance

11.1

Basic safety instructions

The device is maintenance-free. However, a periodic inspection according to pertinent

directives and regulations must be carried out.

An inspection can include, for example, check of:

● Ambient conditions

● Seal integrity of the process connections, cable entries, and cover

● Reliability of power supply, lightning protection, and grounds

WARNING

Dust layers above 5 mm

Risk of explosion in hazardous areas. Device may overheat due to dust build up.

● Remove dust layers in excess of 5 mm.

WARNING

Use of a computer in a hazardous area

If the interface to the computer is used in the hazardous area, there is a risk of explosion.

● Ensure that the atmosphere is explosion-free (hot work permit).

CAUTION

Releasing button lock

Improper modification of parameters could influence process safety.

● Make sure that only authorized personnel may cancel the button locking of devices for

safety-related applications.

NOTICE

Penetration of moisture into the device

Device damage.

● Make sure when carrying out cleaning and maintenance work that no moisture penetrates

the inside of the device.

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Service and maintenance

11.3 Maintenance and repair work

11.2

Cleaning

11.2.1

Cleaning the enclosure

● Clean the outside of the enclosure with the inscriptions and the display window using a cloth

moistened with water or a mild detergent.

● Do not use any aggressive cleansing agents or solvents, e.g. acetone. Plastic parts or the

painted surface could be damaged. The inscriptions could become unreadable.

NOTICE

Improper cleaning of diaphragm

Device damage. The diaphragm can be damaged.

● Do not use sharp or hard objects to clean the diaphragm.

11.2.2

Servicing the remote seal measuring system

The remote seal measuring system usually does not need servicing.

If the mediums are contaminated, viscous or crystallized, it could be necessary to clean the

diaphragm from time to time. Use only a suitable solvent to remove the deposits from the

diaphragm. Do not use corrosive cleaning agents. Prevent the diaphragm from getting

damaged due to sharp-edged tools.

11.3

Maintenance and repair work

WARNING

Impermissible repair of explosion protected devices

Risk of explosion in hazardous areas

● Repair must be carried out by Siemens authorized personnel only.

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11.3 Maintenance and repair work

WARNING

No maintenance interval has been defined

Device failure, device damage, and risk of injury.

● Define a maintenance interval for recurring tests depending on the use of the device and

your own experience.

● The maintenance interval will vary from site to site depending on corrosion resistance.

WARNING

Maintenance during continued operation in a hazardous area

There is a risk of explosion when carrying out repairs and maintenance on the device in a

hazardous area.

● Isolate the device from power.

- or -

● Ensure that the atmosphere is explosion-free (hot work permit).

WARNING

Impermissible accessories and spare parts

Risk of explosion in areas subject to explosion hazard.

● Only use original accessories or original spare parts.

● Observe all relevant installation and safety instructions described in the instructions for the

device or enclosed with the accessory or spare part.

WARNING

Hot, toxic or corrosive process media

Risk of injury during maintenance work.

When working on the process connection, hot, toxic or corrosive process media could be

released.

● As long as the device is under pressure, do not loosen process connections and do not

remove any parts that are pressurized.

● Before opening or removing the device ensure that process media cannot be released.

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Service and maintenance

11.3 Maintenance and repair work

WARNING

Improper connection after maintenance

Risk of explosion in areas subject to explosion hazard.

● Connect the device correctly after maintenance.

● Close the device after maintenance work.

Refer to Technical data (Page 199).

CAUTION

Hot surfaces

Risk of burns during maintenance work on parts having surface temperatures exceeding

70 °C (158 °F).

● Take corresponding protective measures, for example by wearing protective gloves.

● After carrying out maintenance, remount touch protection measures.

11.3.1

Checking the seals

Inspect the seals at regular intervals

Note

Incorrect seal changes

Incorrect measured values will be displayed. Changing the seals in a process flange of a

differential pressure measuring cell can alter the lower range value.

● Changing seals in devices with differential pressure measuring cells may only be carried out

by personnel authorized by Siemens.

Note

Using the wrong seals

Using the wrong seals with flush-mounted process connections can cause measuring errors

and/or damage the diaphragm.

● Always use seals which comply with the process connection standards or are

recommended by Siemens.

1. Clean the enclosure and seals.

2. Check the enclosure and the seals for cracks and damage.

3. If necessary, lubricate the seals or replace them.

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11.3 Maintenance and repair work

11.3.2

Check cable glands

● Check the tightness of the cable glands at regular intervals.

● Tighten the cable glands if necessary.

11.3.3

Replacing spare parts

11.3.3.1

Replacing electrical connections and cable entries

Procedure

1. Read the operating data and the approval information on the nameplates of your device.

2. Order a suitable electrical connection or cable entry for your device (cable gland, sealing

plug or device plug).

To do this, use the article number "7MF7906-..".

Notes for cable glands and device plugs

● When you order a cable gland or a device plug as spare part, consider the following criteria:

- Thread

- Material

- Approval

- IP degree of protection

- Permissible ambient temperature

● The permissible ambient temperature for devices with dust explosion protection deviates

from the permissible ambient temperature of the cable gland and the device plug.

You should therefore not use any cable glands or device plugs from third-party

manufacturers for devices with dust explosion protection.

11.3.3.2

Replacing the display

Removing the display

1. De-energize the device.

2. Use a 3 mm Allen key to loosen the front safety catch.

3. Unscrew the front cover.

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11.3 Maintenance and repair work

11.3.3.3

Replacing the termination board

Removing the termination board

1. De-energize the device.

2. Use a 3 mm Allen key to loosen the front safety catch ②.

3. Open the cover of the electronic connection compartment.

4. Disconnect the cables from the termination board.

5. On the left and right side, remove the recessed-head screws ① that hold the termination

board to the enclosure.

6. Remove the termination board.

Installing the termination board

1. Insert the new termination board so that its contact pins ③ fit on the rear of the termination

board.

2. Work in the reverse order to that described in "Removing the termination board".

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11.5 Disposal

11.4

Return procedure

Enclose the bill of lading, return document and decontamination certificate in a clear plastic

pouch and attach it firmly to the outside of the packaging.

Required forms

● Delivery note

● Return document (http://www.siemens.com/processinstrumentation/returngoodsnote )

with the following information:

- Product (item description)

- Number of returned devices/replacement parts

- Reason for returning the item(s)

● Decontamination declaration (http://www.siemens.com/sc/declarationofdecontamination )

With this declaration you warrant "that the device/replacement part has been carefully

cleaned and is free of residues. The device/replacement part does not pose a hazard for

humans and the environment."

If the returned device/replacement part has come into contact with poisonous, corrosive,

flammable or water-contaminating substances, you must thoroughly clean and

decontaminate the device/replacement part before returning it in order to ensure that all

hollow areas are free from hazardous substances. Check the item after it has been cleaned.

Any devices/replacement parts returned without a decontamination declaration will be

cleaned at your expense before further processing.

11.5

Disposal

Devices described in this manual should be recycled. They may not be

disposed of in the municipal waste disposal services according to the Di-

rective 2012/19/EC on waste electronic and electrical equipment (WEEE).

Devices can be returned to the supplier within the EC, or to a locally ap-

proved disposal service for eco-friendly recycling. Observe the specific

regulations valid in your country.

Further information about devices containing batteries can be found at:

Information on battery/product return (WEEE) (https://

support.industry.siemens.com/cs/document/109479891/)

Note

Special disposal required

The device includes components that require special disposal.

● Dispose of the device properly and environmentally through a local waste disposal

contractor.

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Diagnostics and troubleshooting

12.1

Device status symbols

Device status is shown using symbols on the local display. Additionally, the symbol and

respective text message for each device status can be seen in remote engineering, asset

management or process control systems.

Locally, in measurement view, alarms are shown as a symbol in the lower line of the display.

If several diagnostic states are active at the same time, the symbol for the most critical state is

shown.

Device status characteristics

The following table provides possible cause of device status and actions for the user or service.

The symbols used on the local display are based on NAMUR status signals, whereas symbols

used in SIMATIC PDM are based on Siemens standard alarm classes.

Note

Device status priority conflict - Namur vs Siemens standard

When more than one diagnostic event is active simultaneously, a conflict in priorities may arise.

In this case, the Namur symbol on the local display will differ from that shown in SIMATIC PDM.

● For example: if both diagnostic states "Maintenance demanded" and "Configuration error"

are active,

- Local display (using Namur symbols) will show "Configuration error" as higher priority.

- SIMATIC PDM (using Siemens standard symbols) will show "Maintenance demanded"

as higher priority.

Be aware of the priority for each device status, depending on the interface used.

Note

Namur device status priorities

This device uses Namur device status priorities based on HCF specification.

The sequence of symbols in the table corresponds to the priority of the device status, beginning

with the most critical.

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Diagnostics and troubleshooting

12.1 Device status symbols

Device status symbols

Display

NAMUR

SIMATIC PDM/PLC

– NAMUR NE 107

- HCF

Symbol

Device status

Priority *

Symbol

Device status

Priority *

Failure

Maintenance alarm

Cause: Output signal invalid due to fault in the field device or in the peripherals.

Measure: Maintenance is required immediately.

Maintenance

Maintenance demanded

required

Cause:Output signal is still valid, but wear reserve is almost exhausted and/or a function will be limited soon.

Measure:Maintenance is strongly recommended as soon as possible.

Maintenance

Maintenance required

required

Cause: The output signal is still valid. No functional restrictions have been determined but the wear reservice will most likely

be exhausted in the next few weeks.

Measure: Maintenance of device should be planned.

Function test

Manual operation

Cause: Output signal temporarily invalid (e.g. frozen) due to work being performed on the device.

Measure: Manual mode over HMI or disable the engineering system.

Function test

Simulation mode

Cause: The output signal does temporarily not reflect the process because the output is based on a simulation value.

Measure: Simulation mode over HMI or disable the engineering system or restart device.

Failure

Out of service

Cause: The output signal does not represent the process value. The device mode is set to "Out of service".

Measure: Disable "Out of service" and enable normal operation.

Failure

Configuration error

(red)

Cause: Output signal invalid due to parameter setting, connection error or configuration error in the HW.

Measure: Check hardware configuration of the device over HMI or engineering system.

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Diagnostics and troubleshooting

12.1 Device status symbols

Display

NAMUR

SIMATIC PDM/PLC

– NAMUR NE 107

- HCF

Symbol

Device status

Priority *

Symbol

Device status

Priority *

Out of specifica-

Process value alarm

tion

Cause: Deviations from permissible ambient or process conditions detected by the device (by means of self-monitoring or

based on warnings/errors in the device) indicate that the measured value is unreliable or that deviations from the set value in

the actuators are most likely greater than anticipated under normal operating conditions.

Process or ambient conditions can damage the device or result in unreliable results.

Measure: Check ambient temperature or process conditions. If possible, install device at different location.

Function test

Configuration warning

(yellow)

Cause: Safety validation is not complete.

Measure: Acknowledge safety event in the Functional Safety menu and repeat safety commissioning.

Out of specifica-

Process value warning

tion

Cause: Deviations from permissible ambient or process conditions detected by the device (by means of self-monitoring or

based on warnings/errors in the device) indicate that the measured value is unreliable or that deviations from the set value in

the actuators are most likely greater than anticipated under normal operating conditions.

Process or ambient conditions can damage the device or result in unreliable results.

Measure: Check ambient temperature or process conditions. If possible, install device at different location.

No symbol is

Process value tolerance

displayed

Cause: At least one process value violates one of the process tolerance limits set in the device parameters.

Measure: Check the parameter settings for limits for this application.

No symbol is

Configuration changed

displayed

Cause:The device configuration has changed due to a work process.

Measure: Reset configuration bit memory to delete the diagnostic message.

No symbol is

Good - OK

No symbol is

No assignment

displayed

Cause: Device state ok. No errors from active diagnostics.

Measure: No action required.

* The smallest number indicates the highest level of error severity.

** In SIMATIC PDM, the Siemens standard symbol as well as the corresponding NA\ symbol is

displayed (by the device display).

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Diagnostics and troubleshooting

12.2 Diagnostic messages

12.2

Diagnostic messages

The following table shows the IDs of diagnostic messages and possible causes and

instructions for corrective actions.

Symbols

Message

Cause/Remedy

Event counter 1

The number of overruns of the process value (set in parameters

"Upper limit" and "Monitored value") has reached the threshold.

Number overruns above

threshold

Reset and acknowledge event counter.

Maintenance alarm

Check process conditions.

Check limit monitoring and event counter settings.

Event counter 1

The number of underruns of the process value (set in parameters

"Lower limit" and "Monitored value") has reached the threshold.

Number underruns above

threshold

Reset and acknowledge event counter.

Process value alarm

Check process conditions.

Check limit monitoring and event counter settings.

Event counter 1

The number of underruns of the process value (set in parameters

"Lower limit" and "Monitored value") has reached the threshold.

Number underruns above

threshold

Reset and acknowledge event counter.

Maintenance required

Check process conditions.

Check limit monitoring and event counter settings.

Event counter 1

The number of underruns of the process value (set in parameters

"Lower limit" and "Monitored value") has reached the threshold.

Number underruns above

threshold

Reset and acknowledge event counter.

Maintenance alarm

Check process conditions.

Check limit monitoring and event counter settings.

Event counter 2

The number of overruns of the process value (set in parameters

"Upper limit" and "Monitored value") has reached the threshold.

Number overruns above

threshold

Reset and acknowledge event counter.

Process value alarm

Check process conditions.

Check limit monitoring and event counter settings.

Event counter 2

The number of overruns of the process value (set in parameters

"Upper limit" and "Monitored value") has reached the threshold.

Number overruns above

threshold

Reset and acknowledge event counter.

Maintenance required

Check process conditions.

Check limit monitoring and event counter settings.

Event counter 2

The number of overruns of the process value (set in parameters

"Upper limit" and "Monitored value") has reached the threshold.

Number overruns above

threshold

Reset and acknowledge event counter.

Maintenance alarm

Check process conditions.

Check limit monitoring and event counter settings.

Event counter 2

The number of underruns of the process value (set in parameters

"Lower limit" and "Monitored value") has reached the threshold.

Number underruns above

threshold

Reset and acknowledge event counter.

Process value alarm

Check process conditions.

Check limit monitoring and event counter settings.

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Diagnostics and troubleshooting

12.2 Diagnostic messages

Symbols

Message

Cause/Remedy

Event counter 2

The number of underruns of the process value (set in parameters

"Lower limit" and "Monitored value") has reached the threshold.

Number underruns above

threshold

Reset and acknowledge event counter.

Maintenance required

Check process conditions.

Check limit monitoring and event counter settings.

Device lifetime: Maintenance

Forthcoming end of configured device's lifetime.

demanded

Maintenance is strongly recommended as soon as possible.

Device lifetime: Maintenance

Forthcoming end of configured device's lifetime.

required

Maintenance of device should be planned.

Sensor lifetime: Maintenance

Forthcoming end of configured sensor's lifetime.

demanded

Maintenance is strongly recommended as soon as possible.

Sensor lifetime: Maintenance

Forthcoming end of configured sensor's lifetime.

required

Maintenance of device should be planned.

Service: Maintenance deman-

Forthcoming end of the configured service interval.

ded

Maintenance is strongly recommended as soon as possible.

Service: Maintenance required

Forthcoming end of the configured service interval.

Maintenance of device should be planned.

Calibration: Maintenance de-

Forthcoming end of the calibration interval.

manded

Maintenance is strongly recommended as soon as possible.

Calibration: Maintenance re-

Forthcoming end of the calibration interval.

quired

Maintenance of device should be planned.

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Diagnostics and troubleshooting

12.2 Diagnostic messages

Symbols

Message

Cause/Remedy

Limit monitoring 1

Monitored value is above limit (set in parameter "Upper limit").

Above limit

Process value alarm

Limit monitoring 1

Monitored value is below limit (set in parameter "Lower limit").

Below limit

Process value alarm

Limit monitoring 2

Monitored value is above limit (set in parameter "Upper limit").

Above limit

Process value alarm

Limit monitoring 2

Monitored value is below limit (set in parameter "Lower limit").

Below limit

Process value alarm

Event counter 1

The number of overruns of the process value (set in parameters

"Upper limit" and "Monitored value") has reached the threshold.

Number overruns above

threshold

Reset and acknowledge event counter.

Process value alarm

Check process conditions.

Check limit monitoring and event counter settings.

Event counter 1

The number of overruns of the process value (set in parameters

"Upper limit" and "Monitored value") has reached the threshold.

Number overruns above

threshold

Reset and acknowledge event counter.

Maintenance required

Check process conditions.

Check limit monitoring and event counter settings.

Out of service

The output signal does not represent the process value. The device

mode is set to "Out of service".

Maintenance alarm

Repair required. Contact Technical Support.

Device restart due to unexpec-

Watchdog function has detected an internal device error.

ted program error

Restart the device.

Maintenance alarm

If the problem persists, contact Technical Support.

Alarm sensor limit exceeded

Process value has reached the sensor limit.

Process value alarm

Review process conditions versus product specifications.

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Diagnostics and troubleshooting

12.2 Diagnostic messages

Symbols

Message

Cause/Remedy

Event counter 2

The number of underruns of the process value (set in parameters

"Lower limit" and "Monitored value") has reached the threshold.

Number underruns above

threshold

Reset and acknowledge event counter.

Maintenance alarm

Check process conditions.

Check limit monitoring and event counter settings.

Simulation mode

The device is in simulation mode and one or more of its device vari-

ables are not representative of the process.

Disable the simulation to return to normal operation.

Diagnostics simulated

The device is in simulation mode.

Simulation mode

Disable the simulation to return to normal operation.

Loop current fixed

The loop current is being held at a fixed value and is not responding

to process variations.

Manual operation

Enter the loop current output value for simulation.

Disable the simulation to return to normal operation.

Loop current in saturation

The loop current has reached its upper (or lower) saturation limit and

cannot increase (or decrease) any further.

Process value warning

Adjust loop current scaling.

PV status: uncertain

The value is outside of the physical sensor range. Accuracy may

decrease.

Process value alarm

Check for changes in process conditions or obstructions in vessel.

PV status: bad

The measured value is 10% higher than the physical sensor range.

Maintenance alarm

Review process conditions versus product specifications.

Use a device that fulfills your process conditions.

Supply voltage below limit.

The supply voltage is too low.

Maintenance demanded

Make sure input voltage is within product specification.

Supply voltage above limit

The supply voltage is too high.

Maintenance alarm

Make sure input voltage is within product specification.

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Diagnostics and troubleshooting

12.2 Diagnostic messages

Symbols

Message

Cause/Remedy

Loop current read back error

The loop current does not correspond to the expected value.

Maintenance demanded

Check DAC trim settings.

Restore to factory DAC calibration.

If the problem persists, contact Technical Support.

Process conditions outside the

Uncertain values due to process conditions.

specification

Check installation for abnormal operating conditions.

Process value warning

Connection error to sensor

Potential product damage.

electronics.

Restart the device.

Maintenance alarm

If error continues, sensor electronics may have a defect.

Repair required. Contact Technical Support.

Sensor break

Potential product damage.

Maintenance alarm

Sensor has malfunctioned.

A replacement of sensor is recommended.

Contact Technical Support.

Internal power supply is out of

A replacement of the device is recommended.

allowable range.

Contact Technical Support.

Process value warning

Electronics defect

Defect of device electronics.

Maintenance alarm

A replacement of the device is recommended.

Contact Technical Support.

Non-volatile memory check fail-

Device electronics error.

ure

Restart the device.

Maintenance alarm

If error continues, device electronics may have a defect.

Repair is required. Contact Technical Support.

Volatile memory check failure

Device electronics error.

Maintenance alarm

Restart the device.

If error continues, device electronics may have a defect.

Repair is required. Contact Technical Support.

Invalid device configuration

One or more of parameters are set to invalid values.

Configuration error

Review configuration values and adjust as necessary.

(red)

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Diagnostics and troubleshooting

12.3 Troubleshooting

Symbols

Message

Cause/Remedy

Safety validation mode

Device is in safety validation mode.

Configuration warning

Complete the functional test and confirm that it was successful in the

Functional Safety wizard.

(yellow)

Safety critical device error

Acknowledge the error in menu "Functional Safety". If the device

does not display an error, repeat the safety start up.

Maintenance alarm

Acknowledging safety-related errors (Page 174)

If the problem persists, contact Technical Support.

12.3

Troubleshooting

Symptom

Cause of error

Remedy

Display empty,

No or incorrect supply voltage

Check the voltage at the terminals, the connections and

no transmission

the wiring.

pulses

Display shows

Value too large to appear on the display

Adjust the unit so that a lower value can be displayed,

"#####" instead

e.g. by selecting bars instead of millibars.

of the current

Pressure units [01] (Page 106)

measured value

Below you can find explanations on how to correct problems when enabling Functional Safety.

Information mes-

Cause of error

Remedy

sage on the dis-

play

INVALID CFG

Write protection via user PIN disabled.

Activate write protection via the user PIN.

ACCES

Enable user PIN (Page 139)

INVALID CFG

Wrong characteristic curves selected.

Select one of the following characteristic curves:

TRNFK

● Linear, proportional to pressure (PRESS).

● Linear, proportional to level (LEVEL).

● Proportional to flow rate, two-step linear up to the

application point (VSLN2 or MSLN2).

INVALID CFG

Loop current fixed. Loop test or multidrop

To return to normal operation, disable the loop test or

mode are enabled.

multidrop mode.

LOOPT

Loop test [31] (Page 141)

INVALID CFG

Device in simulation mode: Pressure meas-

Disable simulation to return to normal operation.

ured value is simulated.

SIMUL

Simulate constant pressure values (Page 147)

INVALID CFG

Device in simulation mode: Diagnostics are si-

Disable simulation to return to normal operation.

mulated.

STSIM

Simulate diagnostics (Page 148)

INVALID CFG

Factory settings for Functional Safety are faul-

Replace the device.

ty.

PARAM

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Technical data

13.1

Input

13.1.1

Gauge pressure

Gauge pressure input

Measured variable

Gauge pressure

Measuring span (continuous-

Measuring span¹⁾

Maximum permissible

Maximum test

ly adjustable) or measuring

operating pressure MAWP

pressure

range, max. operating pres-

(PS)

sure (in accordance with

8.3 … 250 mbar

4 bar

6 bar

2014/68/EU Pressure Equip-

0.83 ... 25 kPa

0.4 MPa

0.6 MPa

ment Directive) and max. test

pressure (in accordance with

0.12 … 3.6 psi

58 psi

87 psi

DIN 16086) (for oxygen

0.01 … 1 bar

6 bar

9 bar

measurement, max. 100 bar

1 ... 100 kPa

0.6 MPa

0.9 MPa

and 60 °C ambient tempera-

ture/process temperature)

0.15 … 14.5 psi

87 psi

130 psi

0.04 … 4 bar

20 bar

30 bar

4 ... 400 kPa

2 MPa

3 MPa

0.58 … 58 psi

290 psi

435 psi

0.16 … 16 bar

45 bar

70 bar

0.016 ... 1.6 MPa

4.5 MPa

7 MPa

2.3 … 232 psi

652 psi

1015 psi

0.63 … 63 bar

80 bar

120 bar

0.063 ... 6.3 MPa

8 MPa

12 MPa

9.1 … 914 psi

1160 psi

1740 psi

1.6 … 160 bar

240 bar

360 bar

0.16 ... 16 MPa

24 MPa

36 MPa

23 … 2321 psi

3480 psi

5221 psi

4 … 400 bar

400 bar

600 bar

0.4 ... 40 MPa

40 MPa

60 MPa

58 … 5802 psi

5802 psi

8702 psi

7 … 700 bar

800 bar

0.7 ... 70 MPa

80 MPa

102 ... 10153 psi

11603 psi

Gauge pressure measuring limits

Low measuring limit²⁾

● Measuring cell with silicone oil filling

30 mbar a/3 kPa a/0.44 psi a

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Siemens SITRANS P. Operating Instructions (2019) - page 5