Pepperl+Fuchs SIL LVL-M4 User manual

ISO9001
2
3
Functional Safety
Vibration Limit Switch
LVL-M4 with Electronic
Insert FEL68
Manual

With regard to the supply of products, the current issue of the following document is applicable:
The General Terms of Delivery for Products and Services of the Electrical Industry, published by the Central
Association of the Electrical Industry (Zentralverband Elektrotechnik und Elektroindustrie (ZVEI) e.V.) in its most
recent version as well as the supplementary clause: "Expanded reservation of proprietorship"
Worldwide
Pepperl+Fuchs Group
Lilienthalstr. 200
68307 Mannheim
Germany
Phone: [phone] - 0
E-mail: [e-mail]
North American Headquarters
Pepperl+Fuchs Inc.
1600 Enterprise Parkway
Twinsburg, Ohio 44087
USA
Phone: [phone]
E-mail: [email protected].com
Asia Headquarters
Pepperl+Fuchs Pte. Ltd.
P+F Building
18 Ayer Rajah Crescent
Singapore 139942
Phone: [phone]
E-mail: [email protected]
https://www.pepperl-fuchs.com

Functional Safety LVL-M4 with Electronic Insert FEL68
Contents
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1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.1 Content of this Document . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.2 Safety Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.3 Symbols Used . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2 Supplementary Documentation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.1 Further Applicable Documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.2 Technical Information (TI). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.3 Manual (BA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.4 Brief Instructions (KA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.5 Instruction Manual (SI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3 Requirements and Assumptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.1 Permitted Device Types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.2 Identification Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.3 Safety Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.4 Basic Conditions for Use in Safety-Related Applications . . . . . . . . . . 10
3.5 Useful Lifetime of Electric Components. . . . . . . . . . . . . . . . . . . . . . . . . 13
4 Characteristic Safety Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.1 Device with Electronic Insert FEL68 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5 Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.1 Requirements for Personnel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.2 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.3 Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.4 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.5 Parameter Configuration for Safety-Related Applications. . . . . . . . . . 15
6 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.1 Device Behavior During Power-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.2 Device Behavior in Safety Function Demand Mode . . . . . . . . . . . . . . . 17
6.3 Device Behavior in the Event of an Alarm . . . . . . . . . . . . . . . . . . . . . . . 17

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Functional Safety LVL-M4 with Electronic Insert FEL68
Contents
7 Proof Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
7.1 Basic Test Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
7.2 Test Sequence A, MIN Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
7.3 Test Sequence A, MAX Detection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
7.4 Test Sequence B, Simulation with Test Button or Test Magnet
on the Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
7.5 Verification Criterion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
8 Repair and Fault Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
8.1 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
8.2 Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
8.3 Modification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
8.4 Decommissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
8.5 Disposal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
9 Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
9.1 Structure of the Measuring System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Functional Safety LVL-M4 with Electronic Insert FEL68
Introduction
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1 Introduction
1.1 Content of this Document
This document contains information for usage of the device in functional safety-related
applications. You need this information to use your product throughout the applicable stages
of the product life cycle. These can include the following:
•Product identification
•Delivery, transport, and storage
•Mounting and installation
•Commissioning and operation
•Maintenance and repair
•Troubleshooting
•Dismounting
•Disposal
The documentation consists of the following parts:
•Present document
•Instruction manual
•Manual
•Datasheet
Additionally, the following parts may belong to the documentation, if applicable:
•EU-type examination certificate
•EU declaration of conformity
•Attestation of conformity
•Certificates
•Control drawings
•FMEDA report
•Assessment report
•Additional documents
For more information about Pepperl+Fuchs products with functional safety,
see www.pepperl-fuchs.com/sil.
Note
This document does not substitute the instruction manual.
Note
For full information on the product, refer to the instruction manual and further documentation
on the Internet at www.pepperl-fuchs.com.
Note
For specific device information such as the year of construction, scan the QR code
on the device. As an alternative, enter the serial number in the serial number search
at www.pepperl-fuchs.com.

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Functional Safety LVL-M4 with Electronic Insert FEL68
Introduction
1.2 Safety Information
Target Group, Personnel
Responsibility for planning, assembly, commissioning, operation, maintenance,
and dismounting lies with the plant operator.
Only appropriately trained and qualified personnel may carry out mounting, installation,
commissioning, operation, maintenance, and dismounting of the product. The personnel
must have read and understood the instruction manual and the further documentation.
Intended Use
The device is only approved for appropriate and intended use. Ignoring these instructions
will void any warranty and absolve the manufacturer from any liability.
The device is developed, manufactured and tested according to the relevant safety standards.
Use the device only
•for the application described
•with specified environmental conditions
•with devices that are suitable for this safety application
Improper Use
Protection of the personnel and the plant is not ensured if the device is not used according
to its intended use.
1.3 Symbols Used
This document contains symbols for the identification of warning messages and
of informative messages.
Warning Messages
You will find warning messages, whenever dangers may arise from your actions.
It is mandatory that you observe these warning messages for your personal safety and in order
to avoid property damage.
Depending on the risk level, the warning messages are displayed in descending order
as follows:
Danger!
This symbol indicates an imminent danger.
Non-observance will result in personal injury or death.
Warning!
This symbol indicates a possible fault or danger.
Non-observance may cause personal injury or serious property damage.
Caution!
This symbol indicates a possible fault.
Non-observance could interrupt the device and any connected systems and plants,
or result in their complete failure.

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Introduction
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Informative Symbols
Action
This symbol indicates a paragraph with instructions. You are prompted to perform an action
or a sequence of actions.
▶ Reference to another section or to further documentation
Permitted
Procedures, processes or actions that are permitted.
Forbidden
Procedures, processes or actions that are forbidden.
Symbols in Graphics
1, 2, 3 ... Item numbers
A, B, C, ... Views
Explosion-hazardous area
Non-explosion-hazardous area
Note
This symbol brings important information to your attention.
-
.

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Functional Safety LVL-M4 with Electronic Insert FEL68
Supplementary Documentation
2 Supplementary Documentation
2.1 Further Applicable Documents
•TI01403O
•BA01894O
•KA01429O
2.2 Technical Information (TI)
Planning aid
The document contains all the technical data on the device and provides an overview
of the accessories and other products that can be ordered for the device.
2.3 Manual (BA)
Your reference guide
This document contains all the information that is required in various phases of the life cycle
of the device: from product identification, incoming acceptance and storage, to mounting,
connection, operation and commissioning through to troubleshooting, maintenance
and disposal.
2.4 Brief Instructions (KA)
Guide that takes you quickly to the 1st measured value
This document contains all the essential information from incoming acceptance
to initial commissioning.
2.5 Instruction Manual (SI)
Depending on the approval, the following instruction manuals (SI) are supplied with the device.
These documents are an integral part of the manual.
Note
For further information is available on the product detail page of the devices on the Internet
at www.pepperl-fuchs.com.
Enter the order designation in the search field → Select the appropriate product →
Open the product detail page → Open the Documents tab.
Note
The nameplate indicates the instruction manual (SI) that are relevant to the device.

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Requirements and Assumptions
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3 Requirements and Assumptions
3.1 Permitted Device Types
The details pertaining to functional safety in this manual relate to the device options listed
below and are valid as of the specified firmware and hardware versions.
Unless otherwise specified, all subsequent versions can also be used for safety functions.
A modification process according to IEC 61508 is applied for device changes.
Valid device versions for safety-related use
Basic specifications
L V L – M 4 – (1) (2) (3) (4) – (5) (6) (7) (8) (9) (10) – (11) (12) . L
LVL-M4 Device
LVL-M4 Vibration limit switch for liquids
(1) Type of probe
Xall options
(2) Process connection, sealing surface
Xall options
(3) Process connection
XXX all options
(4) Sensor length, material
Xall options
(5) Housing, material
Xall options
(6) Electrical connection
Xall options
(7) Application, temperature
Xall options
(8) Surface refinement
Xall options
(9) Electrical output
MFEL68, 2-wire NAMUR with test button
(10) Display, operation
Xall options
(11) Approval
XX all options

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Functional Safety LVL-M4 with Electronic Insert FEL68
Requirements and Assumptions
Additional Options
3.2 Identification Marking
SIL-certified devices are marked with the SIL logo on the nameplate.
3.3 Safety Function
The device's safety functions are:
•Maximum level monitoring (overfill prevention, MAX detection)
•Minimum level monitoring (dry running protection, MIN detection)
3.4 Basic Conditions for Use in Safety-Related Applications
The measuring system must be used correctly for the specific application, taking into account
the medium properties and ambient conditions. Carefully follow instructions pertaining
to critical process situations and installation conditions from the instruction manuals.
The application-specific limits must be observed. The specifications in the instruction manuals
and the technical information must not be exceeded.
3.4.1 Density of the Medium
Operation is only permitted with liquids:
•Depending on the configured density setting, the density of the liquid must be as follows:
•if the switch position is > 0.7 the density must be over 0.7 g/cm³
(common water- and oil-based liquids).
•if the switch position is > 0.5 the density must be over 0.5 g/cm³
(e. g., liquefied gas, isopentane, petroleum ether).
•The gas phase above the liquid may not exceed a maximum permitted density value.
The maximum possible gas density depends on the temperature and the device.
(12) Additional approval
SL SIL Functional Safety

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Requirements and Assumptions
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Figure 3.1 Density of gas phase above the medium
3.4.2 Buildup (only for MIN Detection)
The device may only be used in media that do not tend to cause buildup. Buildup is considered
to be any deposits with a thickness of over 0.5 mm (0.02 inch). Buildup can have the effect
that the demand mode of the safety function is not detected and the device will not switch
as intended.
1Switch position for density 0.7 g/cm³
2Switch position for density 0.5 g/cm³
1.000
0.100
0.010
ρ [g/cm³]
0.001
+300
+527
-60
-76
+60
+140
+120
+248
+180
+356
+240
+464
±0
+32
[°C]
T
[°F]
1
2
Warning!
Danger of explosion due to excessive gas density!
Free status is not detected and Covered is always signaled.
The gas density may not be exceeded.
Note
•There is no minimum density for the gas phase.
•Operation in a vacuum is permitted.
•There is no maximum density for the liquid.
•For more information on the levels of diagnostic coverage, refer to IEC 61508-2:2010
Appendix A.2, Comment 2 and Table A.1.
Note
Buildup from 0.5 mm (0.02 inch) is detected with low diagnostic coverage.

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Functional Safety LVL-M4 with Electronic Insert FEL68
Requirements and Assumptions
3.4.3 Solid Particles - Heterogeneous Mixtures (only for MIN Detection)
The medium may not contain solid particles with a diameter greater than 5 mm (0.2 inch).
Solid particles lodged between the tines of the tuning fork can have the effect that the demand
mode of the safety function is not detected and the device will not switch as intended.
3.4.4 Wall Distance
The distance between the tuning fork of the device and the wall of the vessel containing
medium (e. g. tank, pipe) must be at least 10 mm (0.39 inch).
3.4.5 Corrosion
The device may only be used in media to which the wetted parts used are resistant.
Corrosion can have the effect that the demand mode of the safety function is not detected
and the device will not switch as intended.
When using coated sensors, make sure the sensor is not damaged during installation
and operation.
3.4.6 Abrasion
It is not permitted to use the device with abrasive media. The removal of material from
the sensor as a result of abrasion can result in sensor failure.
3.4.7 Flow Velocity
In the case of flowing media, the flow velocity in the area around the tuning fork may
not exceed 5 m/s. Higher flow velocities can have the effect that the demand mode
is not detected and the sensor signals that it is free (uncovered).
3.4.8 External Vibration
In systems exposed to strong external vibrations, e. g., in the 400 to 1200 Hz range
(acceleration spectral density > 1 (m/s²)²/Hz) or ultrasound with cavitation, the safety function
must be verified by simulating a demand mode prior to operation. Accidental switchings
may sporadically occur if a strong frequency from an external source is superimposed
on the frequency of the tuning fork.
Note
Lodged solid particles are detected with low diagnostic coverage.
Note
Corrosion is detected with low diagnostic coverage.
Note
Abrasion is detected with low diagnostic coverage.

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Requirements and Assumptions
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3.4.9 EMC Compatibility
The device is certified in accordance with IEC 61326-3-1 and is thus suitable for general
industrial, safety-related applications. If the specified electromagnetic ambient conditions
are exceeded, the switch status might not be reliably detected. An unshielded cable
can be used between the devices in these environmental conditions. Electromagnetic
interference immunity can be further improved by using shielded cables.
3.4.10 Mounting the Device with a Sliding Sleeve
Particular care is required when mounting the device with a pipe extension in conjunction
with a sliding sleeve. The operator must implement appropriate measures to ensure
that the switch point is not tampered with or that any tampering is reliably detected.
3.4.11 COM Interface
When used as a safety function, there is the option of connecting an additional module
to the COM interface.
Bluetooth: Bluetooth® module VU121
The module may be used for informational purposes only but not as part of the safety function.
It does not have a modifying effect on the safety function.
3.5 Useful Lifetime of Electric Components
The established failure rates of electrical components apply within the useful lifetime
as per IEC 61508-2:2010 section 7.4.9.5 note 3.
According to DIN EN 61508-2:2011 section 7.4.9.5 (national footnote N3) appropriate
measures taken by the operator can extend the useful lifetime.

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Functional Safety LVL-M4 with Electronic Insert FEL68
Characteristic Safety Values
4 Characteristic Safety Values
4.1 Device with Electronic Insert FEL68
Parameters Characteristic values
Assessment type and
documentation Full assessment
Device type B
Mode of operation Low demand mode oder high demand mode 1
Safety function Overfill prevention, MAX detection or dry running protection, MIN detection
Valid hardware version 01.00.ww (ww: any double number)
Valid software version 01.01.zz (zz: any double number)
HFT 0, SIL2 capable
≥ 1, SIL3 capable
SIL 2 – single channel use (HFT = 0)
3 – multi channel use (HFT ≥ 1)
Safety function MIN MAX
su 2 3151 FIT 167 FIT
sd 2 3 5 FIT 41 FIT
dd 2 3 140 FIT 106 FIT
du 2 3 34 FIT 19 FIT
total 2 3 331 FIT 333 FIT
SFF 90 % 94 %
PTC 4Test sequence A 92 % 90 %
Test sequence B 21 % 38 %
PFH 3 3.44 x 10-8 1/h 1.91 x 10-8 1/h
PFDavg for T1 = 1 year 3
(1-channel architecture) 1.51 x 10-4 8.35 x 10-5
Diagnostic test interval 5 60 s, except RAM check  10 min
Reaction time 6 3 s
Table 4.1
1Observe limitation by diagnostic test interval
2FIT = Failure In Time, number of failures per 109 h
3Valid for average ambient temperature up to +40 °C (+104 °F)
For continuous operation at ambient temperature close to +60 °C (+140 °F), a factor of 1.7 should be applied
4PTC = Proof Test Coverage
5All diagnostic functions are performed at least once within the diagnostic test interval
6Maximum time between fault detection and fault reaction

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Commissioning
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5 Commissioning
5.1 Requirements for Personnel
The personnel for installation, commissioning, diagnostics and maintenance must fulfill
the following requirements:
•Trained, qualified specialists must have a relevant qualification for this specific
function and task.
•Personnel must be authorized by the plant owner/operator.
•Be familiar with federal/national regulations.
•Before starting work: personnel must read and understand the instructions
in the manual and supplementary documentation as well as the certificates
(depending on the application).
•Personnel must follow instructions and comply with general policies.
The operating personnel must fulfill the following requirements:
•Personnel are instructed and authorized according to the requirements of the task
by the facility's owner-operator.
•Personnel follow the instructions in this manual.
5.2 Installation
The mounting and wiring of the device and the permitted orientations are described
in the manual pertaining to the device.
5.3 Commissioning
The device is commissioned using the Commissioning Wizard. The commissioning
procedure is described in the manual pertaining to the device.
Prior to operating the device in a safety instrumented system, verification must
be performed by carrying out a test sequence as described in section 6.
5.4 Operation
The operation of the device is described in the manual pertaining to the device.
5.5 Parameter Configuration for Safety-Related Applications
The device settings may not be changed if SIL operation is in progress.
Warning!
The safety function can be impaired.
After commissioning the measuring system, changes to the settings can impact
the safety function.
After changing the settings, perform a proof test to ensure that the safety function is working
correctly.

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Functional Safety LVL-M4 with Electronic Insert FEL68
Commissioning
5.5.1 MIN/MAX Detection Mode
Figure 5.1 Selection of MIN/MAX detection mode
5.5.2 Density Mode
Figure 5.2 Selection of density mode
AAdditional safety equipment
+–
A
>0,5
COM
–+
MIN
MAX >0,7
1
212
>0,5
MIN
MAX >0,7
1
2
ADefault setting (density >0.7 g/cm³), always use this setting where possible.
BSpecial setting (density >0.5 g/cm³), extremely light liquids (e. g., liquefied natural gas,
isopentane, petroleum ether)
U= 0 V
>0,5
COM
–+
MIN
MAX >0,7
1
212
AB

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Operation
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6 Operation
6.1 Device Behavior During Power-Up
The behavior of the device when switched on is described in the relevant manual.
6.2 Device Behavior in Safety Function Demand Mode
The safety-related output signal consists of a current signal according to the NAMUR interface
as per EN 50227(DIN 19234; NAMUR) or IEC 60947-5-6.
•If the status is OK, the current at terminal 2 is between 2.2 to 3.8 mA
•In demand mode, or if a fault is detected in the device, this current decreases
to 0.4 to 1.0 mA
•Currents < 0.4 mA or > 3.8 mA indicate a fault in the cable (short-circuit, cable open circuit
or similar).
IEC 60947-5-6 defines ranges in which the switch points may be, see "Figure 3 - Control input
of the switching amplifier" in the standard. Accordingly, the calculation of the safety-related
characteristic values is based on the requirement that the downstream evaluation detects
the following currents:
•< 0.05 mA reliably detected as a cable open circuit
•> 6.6 mA reliably detected as a short-circuit
6.3 Device Behavior in the Event of an Alarm
The behavior of the device in the event of an alarm is described in the relevant manual.
Danger!
Danger to life from missing safety function
If the safety loop is put out of service, the safety function is no longer guaranteed.
•Do not deactivate the device.
•Do not bypass the safety function.
•Do not repair, modify, or manipulate the device.

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Functional Safety LVL-M4 with Electronic Insert FEL68
Proof Test
7 Proof Test
Proof testing of the device can be performed as follows:
•Test sequence A: Approach the level, or remove and immerse in a medium
of similar density and viscosity
•Test sequence A, MIN detection
•Test sequence A, MAX detection
•Test sequence B: simulation using test button on the device
Warning!
The safety function can be impaired.
The functional integrity of the device in the SIL mode must be verified during commissioning,
when changes are made to safety-related parameters, as well as at appropriate time intervals.
The operator must determine the time intervals.
Warning!
The safety function is not guaranteed during a proof test.
Suitable measures must be taken to guarantee process safety during the test.
Note
Note the following for the test sequences:
•A demand mode or a fault takes absolute precedence over the proof test
and in the measuring system safety path. For this reason, the demand mode must first
be ended or the fault rectified before the proof test can commence.
•The proof test can and may only be performed if the device status is OK.
•The status of the individual output signal is indicated by a measuring device
or a downstream component of the safety path (e. g., PLC, actuator).
•The individual proof test coverages (PTC) that can be used for calculation
are specified in the Declaration of Conformity.
•To monitor the safety-related output signal, it is sufficient to evaluate the response
of downstream components of the safety function. If the different states are correctly
identified there, the test steps are passed.

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Proof Test
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7.1 Basic Test Sequence
Figure 7.1 Basic test sequence
1.1 Status OK
1.2 Output signal for status OK?
2.1 Establish demand mode
2.2 Output signal for demand mode?
3.1 Re-install the sensor that was removed (optional)
3.2 Establish status OK
3.3 Output signal for status OK?
1
2
3
1.1
2.1
3.1
1.2
2.2
3.2 3.3
Note
The output signal can be evaluated based on the response of the following components
of the safety function.

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Functional Safety LVL-M4 with Electronic Insert FEL68
Proof Test
7.2 Test Sequence A, MIN Detection
•Approach the level or
•Remove and immerse in a medium of similar density and viscosity
Proof Test Procedure, Step 1
1. Raise the level or immerse the tuning fork of the sensor that has been removed
into the medium until the tuning fork is fully covered.
If it is not possible to do this with the original medium, a medium of a similar density
and viscosity must be used.
2. Check if the current at terminal 2 corresponds to status OK.
The current must be between 2.2 to 3.8 mA.
Proof Test Procedure, Step 2
1. Lower the level or take the tuning fork of the sensor that has been removed out of the medium
until the tuning fork is completely free.
Wait for the switching delay to elapse (1 s, unless ordered otherwise).
2. Check if the current at terminal 2 corresponds to demand mode.
The current must be between 0.4 to 1.0 mA.
Proof Test Procedure, Step 3
1. Re-install the sensor that was removed (optional).
Wait for power-up (10 s).
2. Restore the status OK by fully covering the tuning fork.
Wait for the switching delay to elapse (1 s, unless ordered otherwise).
3. Check if the current at terminal 2 corresponds to status OK.
The current must be between 2.2 to 3.8 mA.
Note
If the current does not correspond to status OK, there is an fault in the safety path.
The proof test has not been passed and must be aborted
Note
If the current does not correspond to demand mode, there is an fault in the safety path.
The proof test has not been passed and must be aborted.
Note
If the current does not correspond to status OK, there is an fault in the safety path.
The proof test has not been passed and must be aborted.