Safety Manualé

Safety ManualSeries 854 ATG/XTG level gauges

Table of Contents

CHAPTER 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11.1 About this Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

1.1.1 Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11.1.2 Content . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11.1.3 Related Documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

1.2 Basic Skills and Knowledge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11.3 Safety Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

1.3.1 Safety Instrumented Systems, Functions and Integrity Levels . . . . . . . . . . . 1-21.3.2 What standard to use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

CHAPTER 2 Functions, Architecture and Compliance . . . . . . . . . . . . . . . . . . . . . . . . . 2-12.1 Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12.2 Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12.3 Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12.4 Safety-related Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-22.5 Safety Design. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-22.6 Principle of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-32.7 Fault Detection and Reaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

CHAPTER 3 Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13.2 Assumptions and Constraints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13.3 New Installation or Upgrade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

3.3.1 New Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13.3.2 Upgrade. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

3.4 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-23.4.1 Hardware Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-23.4.2 Software Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

3.5 Verification of the Safety Instrumented Function(s) . . . . . . . . . . . . . . . . 3-4

CHAPTER 4 Maintenance Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-14.1 Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-14.2 Diagnostic items . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-14.3 Proof Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2

Part No.: 4417.808_Rev00 854 ATG/XTG level gaugeSafety Manual i

Table of Contents

854 ATG/XTG level gauge Part No.: 4417.808_Rev00ii Safety Manual

Introduction

CHAPTER 1 INTRODUCTION

1.1 About this Manual

1.1.1 Purpose

The Safety Manual provides information about the 854 ATG/XTG level gauge that is relevant for integration of this servo-based level gaugeinto a Safety Instrumented System (SIS). This manual is aimed at technical personnel responsible for such integration.

1.1.2 Content

1.1.3 Related DocumentsIEC 61508 (2010),IEC 61511 (2004),Instruction Manual Series 854 ATG level gauge; Part No.: 4416.220,Installation guide 854 ATG level gauge; Part No.: 4416.225,Instruction Manual Series 854 XTG level gauge; Part No.: 4416.275,Installation guide 854 XTG level gauge; Part No.: 4416.276.

1.2 Basic Skills and Knowledge

Before you start to work on the 854 ATG/XTG level gauge it is assumed that you are certified to do work on safety related systems and devices (i.e. certified Enraf Service Engineer), and that you have appropriate knowledge of:

The concepts and functioning of the 854 ATG/XTG level gauge,The applicable process and equipment under control within the SIS,This Safety Manual,Site procedures,Applicable safety standards (e.g. IEC 61508 and IEC 61511).

Chapter Title Contents DescriptionIntroduction This chapter.

Functions, Architecture and Compliance

Specification of the Safety Instrumented Functions (SIF) that are applied and the architecture(s) these SIFs need to operate. Furthermore relevant certification and compliance information is given.

Implementation Description of - or reference to - details how to achieve and implement the applicable SIFs.

Maintenance Requirements Description of - or reference to - details how to maintain the required Safety Integrity Levels of the implemented SIFs.

Part No.: 4417.808_Rev00 854 ATG/XTG level gaugeSafety Manual 1 - 1

Introduction

1.3 Safety Standards

1.3.1 Safety Instrumented Systems, Functions and Integrity Levels

Processes and Equipment Under Control (PUC/EUC) in the process industry require a high level of safety. Safety Instrumented Systems (SIS) are used to perform Safety Instrumented Functions (SIF). Instrumentation that is used for SIFs, must meet minimum standards and performance levels. Standards like IEC 61508 and IEC 61511 have been developed for this purpose. One of the performance criteria that these standards apply is the Safety Integrity Level (SIL).

IEC 61508 details the design requirements for achieving the required SIL. The safety integrity requirements for each individual safety function may differ. The safety function and SIL requirements are derived from hazard analyses and risk assessments. The higher the level of adapted safety integrity, the lower the likelihood of dangerous failure of the SIS. These standards also address the safety-related sensors and final elements regardless of the technology used.

The 854 ATG/XTG level gauge can be used for a specific SIF that demands SIL 1 or SIL 2. If used in a redundant arrangement, the 854 ATG/XTG level gauge can be applied in loops that require SIL 3.

1.3.2 What standard to use

IEC 61508 has been developed as a generic standard. A framework of standards, incl. IEC 61511, for specific industry sectors were based on this one. The information in the table below is meant as a guideline.

Standard Typical application within the process industryIEC 61508

Functional safety of electrical / electronic / programmable electronic (E/E/PE) safety-related systems

If you are a manufacturer, it is strongly recommended that you apply the IEC 61508.

This generic standard is intended to provide guidance on how to develop E/E/PE safety-related devices as used in Safety Instrumented Systems (SIS).The IEC 61508 serves as a basis for the development of sector standards (e.g. for the machinery sector, the process sector, the nuclear sector, etc.).It can serve as stand-alone standard for those sectors where a sector specific standard does not exist.

IEC 61511

Functional safety - Safety instrumented systems for the process industry sector

If you are an owner/user, it is strongly recommended that you apply the IEC 61511.

This standard addresses the application of SISs for the process industries. It requires a process hazard and risk assessment to be carried out, to enable the specification for SISs to be derived. In this standard a SIS includes all components and subsystems necessary to carry out the safety instrumented function from sensor(s) to final element(s).The standard is intended to lead to a high level of consistency in underlying principles, terminology and information within the process industries. This should have both safety and economic benefits.

854 ATG/XTG level gauge Part No.: 4417.808_Rev001 - 2 Safety Manual


CHAPTER 2 FUNCTIONS, ARCHITECTURE AND COMPLIANCE

2.1 Functions

Beside its standard functions the 854 ATG/XTG level gauge can also be used for a Safety Instrumented Function (SIF) for storage tanks in the oil and gas industry. This function is:

the SIL compliant “overfill protection”.

To establish that the safety parameters for this function of the 854 ATG/XTG level gauge are in the range of SIL 2, it is necessary to:

use the correct architecture; see chapter 2.2 "Architecture",apply the function correctly; for further details see,• chapter 3 "Implementation",• chapter 4 "Maintenance Requirements".

2.2 Architecture

“Overfill protection” in the range of SIL 2 for the 854 ATG/XTG level gauge can be established with the standard architecture. However, specific hardware and software requirements do apply; for further details see chapter 3.4 "Configuration".

2.3 Compliance

Organization Relevant detailsThe 854 ATG/XTG level gauge is considered to be a Type A system in the meaning of IEC 61508. If implemented and maintained correctly, the safety parameters for the “overfill protection” are in the range of SIL 2.

Details of the assessment and cerfitication by TUV Rheinland are recorded in: Report No. W 56 2009 S 1. Certificate No. W 56 2010 C4-1.



2.4 Safety-related Data

The table below specifies the applicable data relating to IEC 61508:

*) The SFF takes into account the failure detection provided by the electronic and software components of the device.

TABLE 2-1 Safety-related data

2.5 Safety Design

The basic 854 ATG/XTG level gauge is used for “overfill protection”, although this is not a SIL compliant function. To establish SIL compliant “overfill protection” a dedicated test has been developed to prove that the gauge is able to measure an upward movement of the product. This test is called the Servo Auto Test 1, and can be executed automatically at a user defined interval. It can also be prompted by a dedicated command for Proof Test purposes. Provided the required configuration is established, the user can set this test to application needs.

Entity / parameter Value RemarksSafety Integrity Level SIL 2 As single channel safety related subsystem.

With a structure establishing a hardware fault tolerance of 1 the device is usable in SIL 3 applications.

Classification of the device Type A

Mode of operation High demand modeContinuous operation

Confidence level 1-α = 70 %

Hardware fault tolerance HFT 0

Diagnostic coverage DC 90 %

Safe Failure Fraction (SFF) SFF = 99.4 % *

Probability of Failure per Hour PFH = 9.71E-08 1/h

MTBF dangerous failures MTBFD 1.03E07 h1173 y

Dangerous failure rate λD = 9.71E-08 1/h97.1 FIT

Safe failure rate λD = 1.61E-05 1/h1387 FIT

Proof Test Interval T = 5 y Once every 5 years.

1. The “Servo Auto Test” feature is patent pending.



The Servo Auto Test makes use of the existing “Principle of measurement” as described in the Instruction Manual, and has the following features:

it is executed automatically and autonomously,it is executed immediately after tank loading, as this is a critical moment,it is executed at regular intervals to prove that the moving parts of the gauge can move as intended,in case of a detected failure,• the appropriate alarm is initiated,• the applicable hardware relays are activated/de-activated

(depending on the mode),during execution the effects of the test are hidden,• i.e. level, status and relays,• for installed equipment (e.g. CIU’s) and systems,the installed base can be upgraded (for applicable prerequisites see chapter 3.3 "New Installation or Upgrade").

2.6 Principle of Operation

Starting from the situation that the displacer (D) is in rest at the product level (PL), the Servo Auto Test consists of these basic steps:

NOTE: The duration of a Servo Auto Test mainly depends on the configuration settings. A typical Servo Auto Test running at default settings may take approximately 15 seconds.

1. The displacer is raised over a configurable distance (cd).

2. The wire tension (wt) is measured while the displacer is being raised.

3. Appropriate actions are initiated, only in case the wire tension exceeds the predetermined limit (X) caused by a mechanical obstruction.

4. The displacer is lowered to the product level.



FIGURE 2-1 shows a graph that represents the actual and measured product levels. The latter in fact is the level of the displacer. The displacer level correctly follows the actual product level, while at set intervals a Servo Auto Test occurs. This indicates that the level gauge is in a healthy state and the moving parts of the gauge can move as intended.

The Servo Auto Test occurences take place at a set interval when the product level is stable, or assumed to be stable. This is the case at product levels PL1 and PL2. During tank filling the Servo Auto Test is temporarily disabled. After end of filling is detected a certain time lapse (tl) passes 1 before the Servo Auto Test is started again. Afterwards Servo Auto Test occurences take place at the set interval again.

The product level (PL) is shown as a function of time where PL1 is the initial stable level and PL2 is the stable level after the tank was filled.

FIGURE 2-1 Servo Auto Test occurences

1. For details about parameters and settings refer to chapter 3.4.2 "Software Configuration"



2.7 Fault Detection and Reaction

During a Servo Auto Test fault detection is conducted as follows:

1. in case the wire tension exceeds its predetermined limit while the displacer is raised, the displacer cycle is interrupted; the displacer will be lowered to the product level;

2. a second displacer cycle is started; in case this cycle is also interrupted the displacer will be lowered to the product level again;

3. a third displacer cycle is started; in case this cycle is also interrupted the displacer will remain at the blocked level;

4. a failure state has now occurred.

Upon a fault detection the 854 ATG/XTG level gauge will initiate fault reaction as follows:

relevant product levels are set to “fail” in their corresponding protocol records (B, D, ZLQ); other product levels keep their last recorded values (innage, ullage and corrected product levels),all product level statuses are set to “fail”,

data item [ES] (Error SPU request) is set to code 0607 (Servo Auto Testfail),

relays (if present) are set in accordance with their “gauge fail” status configuration,

the displacer is kept at the blocked level,new gauge servo commands are not executed, unless the gauge is in maintenance mode.

NOTE: Be aware that the cause of a failure must be removed before you reset the gauge. Otherwise the gauge will come into a fail state again.

The fail state of the 854 ATG/XTG level gauge due to a Servo Auto Testfailure ends when one or more of these actions occur:

the user initiates a reset directly via the reset command (item [RS]),the user initiates a reset indirectly via the exit command (item [EX]),a power down / power up sequence.

Two typical fault situations exist in which faults are detected as described above. Figures 2-2 and 2-3 both show a graph that also represents the actual product level and the displacer level. Each figure shows a typical situation. They represent identical failure states - under different conditions - as a result of a mechanical obstruction.



FIGURE 2-2 shows fault situation 1 (FS1). The product level is raising due to tank filling. Before it actually stops, end of filling is detected. After a certain time lapse (for details see 3.4.2) a Servo Auto Test is initiated and the wire tension exceeds the limit in three subsequent attempts. One of the results of the fault reaction is that filling is stopped. In this situation PL2 represents the intended product level after filling.

FIGURE 2-2 Failure State example - during tank filling

FIGURE 2-3 shows fault situation 2 (FS2). The product level is stable, in this case at PL2. The Servo Auto Test is initiated at set intervals. During a Servo Auto Test the wire tension exceeds the limit in three subsequent attempts.

FIGURE 2-3 Failure State example - product level is stable


Implementation

CHAPTER 3 IMPLEMENTATION

3.1 General

This chapter provides the information that is relevant for correct implementation of the safety-related function(s) of the 854 ATG/XTG level gauge.

3.2 Assumptions and Constraints

The user must install, implement and use the 854 ATG/XTG level gaugeaccording to the conditions that are specified in this manual. The SIL compliant “overfill protection” will operate as intended when:

the standard architecture is present,the correct configuration is installed and commissioned.

Any servo-based level gauge of the type 854 ATG/XTG level gauge that does not comply with these features cannot be used for this purpose.

3.3 New Installation or Upgrade

3.3.1 New Installation

In case you have purchased an 854 ATG/XTG level gauge that is suitable for SIL compliant “overfill protection”, this function is included by design. This means that the required architecture, hardware and software is present in the device. Correct implementation of the function is obtained by setting the required configuration during commissioning.

3.3.2 Upgrade

In case you own an 854 ATG/XTG level gauge, the SIL compliant “overfill protection” can be included by upgrading the device. By ordering the option for SIL compliant “overfill protection” you will receive the required features. Implementation of the upgrade needs to be done by a qualified Service Engineer.

Implementation of the upgrade implies:

for models that have an XPU-2 board installed, a firmware update (EPROM) is required,for models that have an XPU-1 board installed, this must be replaced by an XPU-2 board and a firmware update (EPROM) is required,“commissioning” is done according to the instructions in the 854 ATG/XTG level gauge Installation Manual.


E400083

Notitie

Note: It's highly recommended to use a solid displacer if the 854 ATG/XTG is used for overfill protection.

Implementation

3.4 Configuration

Hardware and software features contribute to the SIL compliant “overfill protection”. TABLE 3-1 specifies the relevant boards the 854 ATG/XTG level gauge must consist of and the relevant firmware. Further details are described in the next paragraphs.

TABLE 3-1 Required boards and firmware

3.4.1 Hardware Configuration

This paragraph describes aspects of the design and integration of the applicable hardware. The required hardware configuration of the 854 ATG/XTG level gauge is achieved by correct use of the specified hardware elements (see TABLE 3-1). No further requirements apply to the hardware configuration.

Board type Revision Firmware VersionXPU-2 current EPROM ≥ H2.8

SPU-1 current No density option ≥ A2.3

With density option ≥ C2.3

SPU-2 current No density option ≥ B2.3

With density option ≥ D2.3


Implementation

3.4.2 Software Configuration

This paragraph describes the steps to achieve the correct software configuration of the 854 ATG/XTG level gauge. The are:

execution of the software settings (commissioning),verification of the function (see chapter 3.5).

To guarantee correct functioning of the “overfill protection” the Servo Auto Test configuration parameters must be set correctly. TABLE 3-2 provides an overview of the applicable items and their settings for configuration (N/A means: not aplicable).

1. Values for heights and distances are given in meters.

2. LD is the standard item to set the Level Dimension: (M = metres; F = feet; I = inches; P = fractions).

3. Protection levels are provided for all Items, depending on the importance of an item.

TABLE 3-2 Software settings

Relevant configuration details per item are described below.

Item [SE]. In case compliant “overfill protection” is required the default value <E>must be kept. In case this function is not required set the value to <D>.

Items [SH] and [SI]. The default settings provide for most common applications. The user can adapt the values in accordance with application or process needs.

Item [SY]. With this item the visibility of Servo Auto Test details on a display and host system is controlled. Preferably the default value <N> of this item is kept. If the value is set to <Y> the host system can show that the gauge is in test.

Item Description Default 1 Min - Max values 1 Eng. unit 2 Prot. level 3

[SE] Servo Auto Test enabled <E> N/A N/A 1

[SH] Servo Auto Test raise height +000.0200 +000.0100 - +000.2500 see [LD] 2

[SI] Servo Auto Test interval time 00060 00001 - 40320 minutes 1

[SY] Servo Auto Test invalidates display and level

<N> N/A N/A 1

[XI] Servo Auto Test level movement detector sample interval

60 10 - 200 seconds 1

[XT] Servo Auto Test level movement detector trip distance

+000.0030 +000.0010 - +000.3000 see [LD] 1


Implementation

Items [XI] and [XT]. These items are related to the movement detector that samples the level in the tank at regular intervals. They are also closely related to each other. They are used to determine if the product level in a tank is stable or moving.

With item [XI] the user determines the time between two consequetive samples by the movement detector. Item [XT] represents the trip distance. If the absolute difference between two samples exceeds the trip distance it is assumed that the tank is being loaded or unloaded.

This movement detection is necessary to disable the Servo Auto Testduring loading and unloading of the tank. It is also used to determine that the product movement stops and a Servo Auto Test can be initiated again. Detection takes place after a certain time lapse. In theory the minimum time lapse is zero (0) seconds and the maximum time lapse is 2 x [XI].Although the default values for items [XI] and [XT] are based on field data and experience, they cannot be automatically used. As circumstances of different tank systems can strongly vary, appropriate values have to be determined for any specific system. It is advised to follow the steps below in the given order to determine the values for these items to avoid over or underrated responses.

1. Determine the maximum deviation of the measured product level in the tank when the product level is stable (PLSTAB-Δ), i.e. no loading or unloading. Level deviations can occur due to weather conditions, e.g. wind on a floating roof tank system.

2. Set the value of item [XT] in the engineering units of the gauge so that it equals: PLSTAB-Δ + 1 mm.

3. Determine the average product level increase per second during loading of the tank in the engineering units of the gauge. This is variable A.

4. Calculate item [XI] as follows: [XI] = [XT] / (1/2 A).

The greater the value for item [XI] the longer it will take before the Servo Auto Test is executed after tank loading is finished. Preferably, this period must be as short as possible to prevent tank overfill due to a mechanical obstruction. This effect occurs because tank loading and unloading does not start and stop suddenly. If these would occur abruptly parts of the tank system can get damaged (e.g. pipes). Therefore opening and closing of valves and starting and stopping of pumps is done gradually.

3.5 Verification of the Safety Instrumented Function(s)

To verify the correct functioning of the “overfill protection” function carry out the procedure of chapter 4.3 "Proof Testing".


Maintenance Requirements

CHAPTER 4 MAINTENANCE REQUIREMENTS

4.1 Purpose

This chapter provides the information that is relevant for correct maintenance of the safety-related function(s) of the 854 ATG/XTG level gauge.

4.2 Diagnostic items

To determine correct functioning of the “overfill protection” the Servo Auto Test a number of diagnostic items are available.

TABLE 4-1 provides an overview of the applicable items and their corresponding value ranges (N/A means: not aplicable).

1. Values for heights and distances are given in meters.

2. LD is the standard item to set the Level Dimension: (M = metres; F = feet; I = inches; P = fractions).

3. Protection levels are provided for all Items, depending on the importance of an item.

TABLE 4-1 Software settings

Relevant details about these diagnostic items are described in chapter 4.3 "Proof Testing".

Item Description Default 1 Min - Max values 1 Eng. unit 2 Prot. level 3

[PE] Level at which the Servo Auto Test last failed

+999.9999 +999.9999 - +999.9999 see [LD] 1

[PL] Level at which the Servo Auto Test was last executed

+999.9999 +999.9999 - +999.9999 see [LD] 1

[PX] Minimum level at which the Servo Auto Test was performed

+999.9999 +999.9999 - +999.9999 see [LD] 1

[PY] Maximum level at which the Servo Auto Test was performed

+999.9999 +999.9999 - +999.9999 see [LD] 1

[PZ] Highest number of Servo Auto Test retries

0 0 - 9 N/A 1

[SN] Number of executed Servo Auto Tests

00000 00000 - 99999 N/A 0

[SQ] Servo Auto Test status N/A N/A N/A 0

[SZ] Time elapsed since last Servo Auto Test

00000 00000 - 99999 minutes 0


Maintenance Requirements

4.3 Proof Testing

To make sure that the “overfill protection” remains SIL compliant a proof test has to be performed once per 5 years.

Points of attention:

It is strongly recommended not to open the 854 ATG/XTG level gauge for proof testing unless test results or other findings demand internal maintenance and/or repair.For the purpose of this procedure it is assumed that the Service Engineer performs the proof test:• preferaby from the control system, using available diagnostic

tools,• as an alternative at the gauge, using a Portable Enraf Terminal

(PET).It is advised to compare the test results with historic data, if available. In this way trends in behavior can be determined.

Follow the steps below in the sequence given:

1. Determine that the examined gauges are certified for SIL compliant “overfill protection”. If not OK - contact plant management for further action. If OK - continue with the next step.

2. Determine the actual status and values of the relevant configuration items for each gauge (refer to TABLE 3-2). Record this data for later reference. Make sure that the values of the configuration items comply with the settings as conducted during commission and/or approved changes. Pay special attention to item [SE] ‘Servo Auto Test enabled’; this should have the default value [E], enabled. If not OK - contact plant management for further action. If OK - continue with the next step.

3. Perform a ‘predictive diagnosis’ for the relevant diagnostic items (refer to TABLE 4-1). Do this for the gauge(s) involved. Record this data for later reference. Note: in this way the behavior of the gauge with respect to the “overfill protection” since the previous diagnosis is shown.

4. Analyze the results of step 3. above: - look for unusual and/or exceptional behavior, - compare the data with historical data, and look for trends, - prepare a report for plant management; discuss any highlights, - initiate preventive and/or corrective maintenance if necessary.

5. Reset the relevant diagnostic items to their default values. This applies to the items that have a ‘Protection level 1’ (see TABLE 4-1).

6. Finally, execute the required certification renewal procedure.


E400083

Notitie

Different time interval maybe applicable, depending on application or local safety regulations

4417808 - Revision 0February 2011© 2011 Honeywell International Inc.

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