Intrinsic Safety

AN9003 - A Users Guide to Intrinsic Safety

Intrinsic Safety is the natural choice for all low voltage instrumentation problems. This application note looks at the design, installation, maintenance and repair of Intrinsically Safe equipment and also considers the risks associated with dust.

Keywords: Intrinsic Safety, hazardous area, zone 1, gas, dust, installation

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Reliability & Functional Safety

AN9025 - An Introduction to Functional Safety and IEC 61508

This application note is intended to provide a brief introduction to the IEC 61508 standard, and to illustrate how it is applied. It does not claim to be a complete interpretation of the standard; that would be impossible in so few pages. However, it should be helpful, especially if the subject is new to you.

Keywords: Functional safety, SIL, IEC61508

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AN9030 - Availability, Reliability, SIL

A brief look at some of the terms that are frequently used in the world of SIL (Safety Integrity Level) and IEC 61508. Some helpful definitions of the terms and how to calculate them. Important basic information for those newly venturing into this potentially confusing area.

Keywords: SIL, MTBF, MTTR, PFD, availability, reliability.

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AN9036 - Reliability considerations for IS interfaces

There is an increasing interest in the use of a statistical approach to all tyes of reliability analysis. This looks at three aspects of the reliability of a simple Zener diode barrier used in a 4-20mA transmitter loop and suggests that this approach could lead to a different way of considering risk.

Keywords: SIL, availability, reliability, failure rate.

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Wireless Applications

AN9028 - Asset Tracking in Hazardous Areas

Asset Tracking of eqwipment and personnel is becoming an important component of a facility’s HSE compliance. The MTL range of Intrinsically Safe (I.S.) Ethernet products make it possible to have a suitable wireless infrastructure to access the associated chip readers anywhere in a facility, regardless of area classification.

Keywords: Wireless, Intrinsically Safe, Ethernet, PoEx.

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AN9029 - Wireless Plant: Complete Coverage

Wireless communications are becoming an important part of a company’s infrastructure both outside and inside a plant environment. The wireless infrastructure can be used for both network and process data communication, however coexistence must be considered early in the design of plant-wide wireless systems. MTL are unique in being able to provide a mesh network infrastructure complete with I/O, gateways and IS equipment capabilities.

Keywords: Wireless, Intrinsically Safe, Ethernet, PoEx.

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AN9033 - Wireless Modbus systems

Modbus is the most widely used communications protocol in process industries today. MTL’s wireless solutions can connect a range of Modbus devices over a standalone network, or transfer the data to a host computer for remote monitoring and control. Both Modbus TCP and RTU protocols are supported, plus the ability to convert between them, which maximises the options when adding devices to a network.

Keywords: Wireless, Modbus, WLN-2000.

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AN9038 - HART Backhaul over Wireless

Industry standard HART™ enabled instrumentation gives benefits beyond that of standard 4-20mA. MTL wireless products can transport this HART™ information over a long or short range wireless connection making this important diagnostic information available at several remote locations on a plant or site.

Keywords: Wireless, HART, RS232, RS485.

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AN9026 - FISCO Intrinsically Safe Fieldbus System

A practical guide to the selection, installation and maintenance of equipment complying with the Fieldbus Intrinsically Safe COncept (FISCO) for fieldbus systems in Zone 2 and Division 2 hazardous areas. The document begins with a discussion of the origins of FISCO and follows with a review of the main elements to be considered when assembling FISCO systems. Further sections develop each subject in more detail. The intention is to provide clear guidance to new and experienced fieldbus users.

Keywords: FISCO, fieldbus, intrinsically safe, hazardous areas, FOUNDATION Fieldbus, H1

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AN9027 - FNICO Non-Incendive Fieldbus System

A practical guide to the selection, installation and maintenance of equipment complying with the Fieldbus Non-Incendive COncept (FNICO) for fieldbus systems in Zone 2 and Division 2 hazardous areas. The document begins with a discussion of the origins of FNICO and follows with a review of the main elements to be considered when assembling FNICO systems. Further sections develop each subject in more detail. The intention is to provide clear guidance to new and experienced fieldbus users.

Keywords: FNICO, fieldbus, hazardous areas, FOUNDATION Fieldbus, H1

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AN-BYRES119 - Using Tofino to control the spread of Stuxnet Malware

This application note describes how to use the Tofino Industrial Security Solution to prevent the spread of the Stuxnet worm in both Siemens and non-Siemens environments.

Keywords: Tofino, Stuxnet, Network Security

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TAN1001 - Lightning surge protection for electronic equipment - a practical guide

This publication discusses the nature of the threat to electronic instrumentation and communications networks posed by voltage surges induced by lightning or other causes. The practical application of surge protection devices (SPDs) designed to prevent damage from such sources is described.

Keywords: Surge protection, lightning, electronic equipment

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TAN1002 - Lightning & surge protection - basic principles

This publication discusses the nature of the threat to electronic instrumentation and communications networks posed by voltage surges induced by lightning or other causes. The practical application of surge protection devices (SPDs) designed to prevent damage from such sources is described.

Keywords: Surge protection, lightning, electronic equipment, communications, networks, SPD

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TAN1003 - Earthing guide for surge protection

This publication discusses the major aspects of earthing surge protection devices (SPDs). The relationship between SPD earths and the earthing of associated instrumentation or other equipment with which the devices are used is also considered.

>Keywords: Surge protection, lightning, electronic equipment, earthing, grounding, SPD

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TAN1004 - Surge protection for intrinsically safe systems

This publication discusses the nature of the threat to intrinsically safe instrumentation in hazardous areas from voltage surges induced by lightning or other causes. The practical application of surge protection devices (SPDs) is also considered taking into account the certification/approvals requirements.

Keywords: Surge protection, lightning, electronic equipment, SPD, IS, intrinsic safety

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TAN1005 - Surge protection for Zone 0 locations

This note discusses the surge protection requirements of intrinsically safe circuits entering a Zone 0 hazardous area. It analyses the potential gradients generated by lightning strikes and their possible routes of invasion. The alleviation of the problem at the Zone 0 interface transfers the problem elsewhere and an adequately safe pragmatic solution is proposed.

Keywords: Surge protection, lightning, electronic equipment, SPD, IS, intrinsic safety, Zone 0

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TAN1006 - Surge protection for weighing systems - an application guide

This publication discusses the nature of modern weighing systems and describes the various methods by which surge protection can be applied to load cells (digital and conventional), to control systems, etc, within the weigh cabin and to external system links.

Keywords: Surge protection, lightning, electronic equipment, weighing systems, load cells

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TAN1007 - Surge protection for Local Area Networks

This publication discusses ways in which Local Area Networks can be damaged by lightning-induced transients, and how they can be protected economically.

Keywords: Surge protection, lightning, electronic equipment, LAN, networks

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TAN1009 - Surge protection for electrical power installations

This publication discusses the affects of surges and lightning induced overvoltages on ac power systems. The note will introduce the source of many common transients and surges and suggest the application of surge protection devices in this area. Finally, typical examples are shown for common installations.

Keywords: Surge protection, lightning, power systems, transients

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TAN1010 - Lightning & surge protection for fieldbus systems

This publication discusses the major aspects of a fieldbus system including the background history, highway components, I.S. applications and surge protection required to ensure that the Fieldbus system is protected against any destructive effects caused by lightning.

Keywords: Surge protection, lightning, fieldbus

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