Machine Safety Training for Beginners Introduction to Machine Safety

Machine Safety Training forBeginners

Introduction to Machine Safety

Schneider Electric 2- Division - Name – Date

Contents

●Introduction to Machine Safety

●Annexes:●Additional Products Info

●Standards

●Safety Principles

Introduction to Machine Safety

Safety basics and offer presentation


Danger and Risk

●Most people have a misunderstanding between danger / hazard and risk. A danger is ever present whereas risk is the possibility of that danger happening.

Consider the following two statements: ● A hungry tiger is dangerous

● A hungry tiger is risky

●A hungry tiger is dangerous, but it is only a risk if it is in your vicinity.●We can avoid or reduce risk by bounding danger

(tiger is locked in the ZOO, so the risk to be attacked is very low)

ZOO

Risks are events or conditions that may occur, and whose occurrence, if it does take place, has a harmful or negative effect


●Investing in machine safety● Health & safety for all personnel

● Cut costs associated with:● Physical injuries● Insurance premiums● Lost production, penalties ● …

● Increased productivitydue to the prevention of accidents

● Better failure detection● Worker confident at work● Improving maintenance efficiency● …

Protect People and Increase Productivity


Safety - Acceptable Risk Level

●Risk 0 does not exist but it must be reduced up to an acceptable level

●Safety is the absence of risks which could cause injury or damage the health of persons.

●It’s one of the machine designer job to reduce all risks to a value lower than the acceptable risk.


Machine Safety as Global Concept

●Safety must be taken into account:

● already in the design phase● and must be kept in place throughout

all stages of a machine’s life cycle:> Transportation> Installation> Adjustment> Operation, Production> Maintenance> Dismantling

●Safety is necessary to obtain CE mark

Maintenance

Design and production

Installation and implementation

Operation


Safety Chain Principle

Use devices that comply with

safety standards

Monitor & analyze the information

Safety-oriented signal processing

Catch the information

Safeguarding to protectpeople from hazard

Initializing & control of hazardous machine

Emergency stopoperations

Stop the dangerous machine

Signaling

Disconnectionand locking

power supply

Safe drive technology

Safe signal transmission

Safe connection & communication of functional units or segments


●Catch the information● Emergency stop/ Trip wire

● Control of access of hazardous zones

●Occasional

●Free to continuous

● Starting & enabling of dangerous movements

Preventa - Your Full Safety Chain Solution


●Monitor the information● Safety modules

● Controllers

● Safety PLC

● ASi safety at work



●Stop the machine● Variable drives

● Vario

● Contactors

●Audible and visible warnings



European legislation and the standards

●The EU Machinery Directive (98/37/EC), ● As a European law, defines the targeted levels of Machine Safety.● Compliance with machinery directive is necessary

● to get the CE mark, and to Allow the free circulation of machinery within the European Union.

● A new version will be effective at the end of 2009

●The European harmonised standards ● Established technical specifications which comply with the requirements of

the related directives.● Compliance with European Harmonised standard give compliance with the

related directive

●Comply with the European harmonized Standards is the simplest way to comply with the Machinery Directive


The Process to Comply with CE Marking

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Safety Switches offer

Heavy Industrial Machines (Metal enclosure)

Light Industrial Machines (Plastic enclosure)

Guard switches

XCS A / B / C / E

XCS MP / PA / TA / TE

Safety switches with rotary or spindle actuator

XCS PL / TL / TR / PR

Limit switches

XCS D / M

XCS P

Coded magnetic

XCS DM / DM3 / DM4

Additionaloffer info


Safety Mats offer

XY-TP1 XY-TP4XY-TP3XY-TP2

All pieces can be electrically interconnected depending on the shape and size needed to protect

from accessing danger area

500x500 mm 500x750 mm 750x750 mm 750x1250 mm



Light Curtains offerType 4 Type 2

Finger and Hand protection Body protection

Compact model Slim model

Hand protection Body protection

XUS-LBXUS-LPZ XUS-LPB XUS-LNG

XPS-CM

XU2-S XU2-S

Modular beam

XUS-LDM

XUS-LDScascadablesegments

2 versions are possible:- active (left) receiverSn: 0,8…70 m- passive (right) rcvrSn: 0,8…8 m

52 mm X 55 mm2x PNP + 1x PNPIP67

XUS LPDMProgramming and Diagnostic Module

Sn: 0.3…15 m

28.5 mm X 32 mm

2 solid-state PNP

IP65

Sn: 0,75…1,2 m

Diam 18

2x N/O + 4x PNP

IP67

Sn: 0.3…20 m

38 mm X 50 mm

2x PNP + 1x PNP(or NPN)

IP65

NEW

NEW


NEW


Positioning of the Safety Solutions

Machine Complexity

One Safety Function

Multiple Safety

Functions

Process and Safety Island

Safety System

Safety

Simple Machines

Repetitive Machines

Complex Machines

Manufacturing Process

Batch Process

Safety Devices (Dialogue and Detectio

n)

Safety Modules

Safety PLC

AS-interfa

ce Safety

Decentralised I/O

Safety Controlle

rs

Centralised I/O


Safety Processing Devices offer overview

Non-configurable modules

Configurable controllersProgrammable

PLCs No software With software

XPS-A/B/C/D/T/V XPS-MP XPS-MC ASISAFEMON XPS-MF

1 safety

function

2 independent

functions

Multiple independent

functions

1 or 2

independent

functions

Multiple

functions


Safety PLC offer

Compact Solution: 90% ofapplications

- Wiring cost reduction - Network flexibility

Modular Solution: 10% of applications– Speed: Response time– Large application memory– High network flexibility

Safety Remote IO

XPSMF IO Cards

Digital & Analogue IO

XPSMF1 Digital Input

XPSMF3 Input & output

XPSMF2Digital Output

Rack Power supply unit

Central processing unit

Digital: Input; Output; Input & OutputAnalogue: Input;

Output Counter Input

XPSMF35 Safety PLC

XPSMF40 Safety PLC

Digital IO

XPSMF30 Safety PLC

XPSMF31 Safety PLC

Digital IO

Digital IO



Safety Controller offer

ModbusModbus, CANopen

Modbus, Profibus DP

XPS MC XPS MP

Bus connection



Safety Modules offer

XPSAC XPSAF XPSATE XPSAV

Time Delay fnc

XPSAFL XPSAR XPSAK XPSVC XPSBA XPSBC XPSBF

Additional safety contacts modules

XPSECMXPSECP

4 or 8 N/O

XPSLCD XPSLCM XPSCM XPSDMB

Enabling

switch

E-stop, Switch, Trip-wire

Light curtains

Two-hand control stations

Light curtains

Type 2 or Type 4

Single beam sensors

Single beam sensors

XPSDME

For applications requiring safety time delay

XPSTSAXPSTSW

XPSVNE XPSDA

Zero speed detection

Liftscontrol

XPSPVTXPSPVK

XPSOT

Press application

Type 2



AS-i Safety@Work offer

ManagementSafe and logical functions

ASI SSSLB ASI SSLC ASI SSLLS ASI SE ASI SSL ASI SAFEMON.. ASI SA01

Network

Slave

MonitorSoftware

ASi-Safety at Work on the standard ASi cable

EmergencyStop M12 entries ISO M16 entry Control stations

Category 4 monitor Analyser

ASI TER

Adjustment terminal


Stéphane Lagache

Picture?+ software name?


Safety Dialogue Solutions

Emergency stop function to avoid the accident or reduce

it’s consequences

Allow access to a danger zone and stop the machine when it is

not actuated

Start or Stopthe machine

Authorize starting of a dangerous machine

movement once people are outside the danger zone

E-stop and Trip wire switches Two-hand control Enabling grip switch Foot switches


E-stop and Trip wire offer● Emergency Stop

pushbuttons for:● machine tools,● foundries, presses,● automobile industry

● Emergency Stop pushbuttons for:

● assembly and packaging machines

● paper, cardboard and woodworking machines

● food/beverage processing and chemical industries

● Control stations for:● assembly and packaging

machines,● paper, cardboard and

woodworking machines,● food/beverage processing,

chemical and automobile industries, mechanical presses

Metal bezel and fixing collar Plastic bezel and fixing collar Plastic enclosure

XAL KXB5 AXB4 B

● Trip wire switches for:● conveyor systems,● materials handling,

machine tools,● electrical testing

stations

Protection ≤15 m Protection ≤50 m Protection ≤100 mor 2x 100 m

XY2 CH XY2 CE XY2 CB



Two-hand Control Station

XY2 SB

Enabling Switch

XY2 AU

Single pedal switches - Metal

Double pedal switches - Metal

XPE RXPE M

Single pedal switches - Plastic

XPE G XPE B

XPE Y XPE A




Control and Signaling offerTwo-hand Control Station, Enabling Switch and Foot Switch offer


Mini-Vario and VARIO Switch Disconnectors

Front Mounting Enclosed

VCCD / VCCF

Backplate mounting in enclosure

VCD / VCF

Door mounting

VCFN / VCF*



Reminder

●The safety chain protects your personnel, material and increases your productivity

●Safety must be taken into account from the design stage to end of the life of your installation

●Schneider Electric offers complete safety chain solutions


T hanksfor your attention

Additional Products Info


Safety Switches

● Working principle: ● The start command for the machine can only be initiated following correct operation of

the guard switch.● On its release, the N/C safety contacts are opened by positive action or, for coded

magnetic switches, change state (must be monitored using a PREVENTA safety module)

● Advantages:● The guard only has to move a small distance

for the switch to be activated.● Ideal for:

− Guards without hinges or guides connectingthem to the machine

− Guards that can be disassembled without tools

● Disadvantage:● Can be bypassed if an actuator key not attached

to the guard is used

Open Closed

Guard

Key

Key


Functionality

● Actuator Key● Common to all metal or plastic case safety switches

● Square turret head which can be rotated through 360° in 90° steps● Contact states remain unchanged when loosening the

fixing screw (head remains attached to the body)

● Safety of operation● 3-pole contacts for metal cases and 2-pole or 3-pole for plastic cases● Without or with intelocking and locking of actuator by solenoid● Manual locking/unlocking by pushbutton or key operated lock

● Correspondence to environment● XCS metal for heavy duty environment● XCS plastic for light and normal environment


Functionality - Lever or Spindle

● Application● Immediate stopping of the dangerous movement as soon as the lever or spindle

reaches an angle of +5° or -5° from the home point 0°

● Degrees of freedom● Lever-operated XCSPL and XCSTL: +180°, +/-90° or -180° depending on the product

reference● Spindle-operated XCSPR and XCSTR: +/-270°

● Levers – Straight or elbowed, making the lever switches suitable

for use with all types of hinged guards:● flush with the machine framework (use a switch with an elbowed flush lever)● overhanging in relation to the machine framework (use a switch with a straight lever)

● Spindle operators● 2 spindle lengths: 30 or 80 mm


Coded magnetic Switches and Systems

●Plastic case system for use on machines with low inertia

(quick rundown times)

●Coded Magnetic Switches● 2-pole (XCS DMC/XCS DMR/XCS DMP) or 3-pole (XCS DMP) contacts

● In safety circuits must always be used in conjunction with a Preventa safety module

●Coded Magnetic Systems● Self-contained range: category 3 (SIL 2) XCS DM3 and

category 4 (SIL 3) XCS DM4

● Integrated self-monitoring using micro-processors, no need to use external safety module


Mounting and Directions of Approach

●3 options for transmitter/receiver mounting: face to face, side to side, face to side

● 2 directions of approach for each type of mounting (except XCS-DMR)

XCS-DM3 /4


Functionality – Coded Magnetics 1

●Working principle – Reed Switch:

● Use Reed technology: contact activated by magnetic field

● Composition: A pair of ferromagnetic blades encapsulated in a hermetically sealed glass tube containing inert gas which prevents any oxidation/corrosion of the blades

S N

Safety output contacts

Coded magnets

=

S N

N S


Functionality – Coded Magnetics 2

●Working principle – Hall Effect:● The receiver part has a conductor (Hall element) with an established current

flow

● The presence of a perpendicular magnetic field will cause a difference of potential on opposite edges of the hall element, this is what is known as the Hall Effect

● In the absence of a magnetic field, the measured voltage is insignificant

● The hall voltage is directly proportional to the strength of the magnetic field

Image source = Wikipedia

Hall Voltage

1 – Electrons2 – Conductor (Hall sensor)3 – Magnet4 – Magnetic field5 – Power supply


Miniature Safety Limit Switches

●With head for linear movement (plunger) or rotary movement (lever)● narrow metal miniature case XCS M

● compact metal XCS D or plastic XCS P case

●With protective plate, preventing both access to the fixing screws or adjustment of the head by no authorised personnel.

●Torx fixing screws.

●Used for machines without or with low inertia:● Used in pairs, with one switch in positive mode,

and the other in negative mode

● In combined mode, they can, when connected to

Preventa modules, provide a Category 4 safety control system

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Safety Mats

●The safety mats function is to protect operator in front of the dangerous machines in the harsh environnent (where optical solution can‘t be used)

●Features● Detect of people or objects weighing more than 20Kg crossing or falling on

the mats surface

● Modular surface – electrically interconnectable, without loss of sensitivity

● “Protect Area Design” software configuration tool is available for simplification of installation

● Simple wiring

● Insensitive to dusty environment


Safety Mats Characteristics

● A safety mat comprises:● a sensing zone 1● a border comprising aluminium rails 2● and rail corners which secure the assembly 3

● Working principle: ● Two stainless steel plates separated by polyurethane foam● On activation (object on mat) short-circuit between plates will be detected

● Advantages● Rigidity for transport● Detection at any point

● Disadvantage● Too heavy objects can damage plates and they

will short-circuit permanently (max. load 800N/cm2)However, the short-circuit guarantees tripping safety


Protect Area Design software● Main function:

● Creation of an application based on light curtains and/or safety mats

● Benefits:● Quick chose of the products needed for the application● Huge winning time compare to the application manage without

PAD* software● Allow, with the “SysQuote” software associated in

option to quote the complete applications

● Results:● Component selection (products description)

● Graphical representation of the configuration● List of selected components (references and

quantities)● Configuration of products

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Light Curtains

● This is an electro-sensitive optical safety device used to protect people working near dangerous machines.

● When the light curtain senses entry into the protected zone by an object, it sends a stop signal to the guarded machine

● Light curtains can replace mechanical guards IF the operating environment is not polluted (splashing, spattering etc. )

● Facilitate operator’s work if frequent access to the danger zone is needed● Easier access for maintenance operations

● Applicable for machines where dangerous movement can be stopped quickly

● Mechanical and hydraulic presses● Molding presses● Stamping, forming and automated assembly machinery


Light Curtains System Components


Light Curtains Characteristics

●Detection Capacity (d) is the smallest object (diameter) that safety light curtain is capable of detecting with absolute certainty (finger, hand or body detection)

d = P + e● P - distance between the axis of 2 adjacent beams

● e - diameter of the beams

●Protected Height (Hp) is the zone (or height) within which an object of equal diameter to the detection capacity d is detected with absolute certainty

d 14 mm – finger

d 30 mm – hand

d 70 mm – body


Light Curtains Standard Functions – 1/2

●Automatic/Manual protection mode is what standard EN/IEC 61496 calls start (or restart) interlock of the safety light curtain

● in AUTO mode: on power-up or after the beams have been cleared, the light curtain resets itself automatically

● in MANUAL mode: on power-up or after the beams have been cleared, the light curtain keeps its output safety circuits in the “open” position. Pressing (and releasing) the reset button will cause actual resetting of the light curtain

●Monitoring of external switching device (EDM - External Devices Monitoring)

● consists of monitoring the function (open or closed), together with the time taken to reach that condition, of the machines power switching components (contactors)

On power-up, the XUS-L system looks for an EDM closed condition. If this is found, it will enter a state consistent with the selected operating mode. When the XUS-L system enables its safety outputs, it monitors the EDM for a closed-to-open transition. This transition must occur within 300 ms or the XUS-L system considers the EDM alarmed and will then enter an alarm state.


Light Curtains Standard Functions – 2/2

●Test function is a feature that allows a machine controller to simulate an interruption of the sensing field.

● The order to start the test is given by the machine during a non-hazardous phase in which it performs a self-test of the entire safety system including the light curtain (ex., on power-up)

● If the result of the test is not conclusive, the light curtain controller sends a stop signal to the connected machine

●Response time – the maximum time between detection of the beam being interrupted and the change in state of the OSSD of the light curtain

● OSSD – Output Switching Safety Device


Light Curtains Specific Functions – 1/3

●Muting is the temporary automatic disabling of the light curtain’s detection function, which allows objects to access the hazardous zones during the process without stopping the machine

● Activation (or deactivation) is achieved by means of standard sensors (photo-electric or other)

● When activated, a signal is sent to the automation system and signaling informs the operator that they are not protected


●Blanking is the disabling of a selected group of light beams in the light curtain (and not all the beams as with muting)

● This function allows the presence of objects during process operations

● Caution when using:● The detection capacity changes This imposes a greater safety distance● Additional protection is necessary on each side of the "blanked" zone, in

order to prevent any intrusion into the free areas




●Floating Blanking – is the inhibition of one or two light beams (adjacent or otherwise), anywhere in the light curtain

● An obstruction can move or "float" inside the sensing zone without generating a stop signal

●Blanking plus floating blanking

functions can be combined. This prevents the light curtain from being accidentally tripped if the part blanking the beam starts to vibrate (making it interrupt or trigger the signal)

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Safety Processing Devices

●The safety processing devices contains one or two safety circuit(s) for processing input signals provided by Detection or/and Control units and forming safety or/and signaling outputs.

●They provide safety solutions for each safety function. The Schneider Electric range of safety control solutions comprises four product families:

● dedicated safety modules with one or two safety functions● configurable controllers managing several safety functions● safety PLCs used within complex and distributed over SafeEthernet safety

system● safety monitors and interfaces dedicated to the AS-Interface system,

allowing use of a single medium for control and safety

Input Logic Outputim im

Input Logic Outputim im


Programmable Safety PLC

● The XPS-MF range of Safety PLCs and I/O are Programmable Electronic Systems (PES) that can be interfaced to safety and non-safety devices to carry out safety or non-safety related tasks for machinery and equipment

● XPS-MF safety PLCs and Distributed I/O modules are tested and certified by TÜV for functional safety in accordance to CE and standards:

● IEC 61508 up to SIL 3,● EN 954-1 up to category 4

● SafeEthernet protocol over Ethernet is certified for safety-related communication between XPS-MF products

● XPSMFWIN is the project management software used to:● Configure the safety PLCs,● Develop the user applications using FBD and SFC languages (IEC 61131-3),● Carry out on-line tests and diagnostics…

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Safety Controllers

● XPS-MP – safety controller module with 15 preprogrammed (only 2 independent fncts can be chosen) safety functions provide a solution for the majority of safety applications up to category 4 conforming to the standard EN 954-1/ISO 13849-1

● 6 safety outputs (3 N/O per function)● 3 solid-state outputs (for signaling to the process PLC)

● XPS-MC – configurable safety controller designed to provide a safety solution with conformity up to category 4 of standard EN 954-1/ISO 13849-1 and up to SIL3 requirement of standard IEC 61508

● Safety inputs: 16 or 32● Safety outputs: 6 solid-state + 2 x 2 relay outputs (4 relay outputs with guided contacts)● NON-safety communication via: CANopen, Profibus and Modbus

● XPSMCWIN configuration software for XPS-MC● Free of charge “Service version” is available for customers

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Safety Modules

●Safety Modules – designed to provide a safety solution for the majority of safety applications. Each safety module performs one or few preprogrammed safety functions (emergency stop, switch, light curtains, two-hand control station, etc. monitoring)

●Modules enclosed into housings of width:● 22,5 mm– 2 to 3 safety outputs + 1 to 2 additional outputs

● 45 mm – 3 to 6 safety outputs + 2 to 5 additional outputs

● 90 mm – 6 to 8 safety outputs + 2 to 6 additional outputs

●Up to the Category 4 max● depends on the structure and other products used in the solution

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AS-i Safety@Work Concept

●The Actuator/Sensor Interface or AS-Interface is the only worldwide standardized bit-oriented fieldbus:

● Power supply, standard data and safety-oriented data transfers on the same 2-wire yellow cable

● The AS-i Safety at Work system can be used to create safety functions up to Category 4

●AS-interface "Safety at Work" allows direct safety components connection on the cable:

● Emergency stops

● Limit switches

● Light curtains

● Contact less sensors, etc.

SAFETY AT WORK


AS-i Cabling - Maximum security

● AS-i significantly improves machine’s reliability, availability and safety:● Cabling errors are eliminated:

● A rubberized 2-wire cable (2 x 1.5 mm2)● The profile section prevents stations being

connected with incorrect polarity● Risk of electrical connection failure greatly reduced● High immunity to electromagnetic interference (EMC)● The machine’s safety function is fully integrated with AS-Interface Safety at Work.

● Connecting modules:● Contact blades penetrate the rubber jacket and make contact with the two wires● Removing blades from cable causes no problems - cable is “self-healing”.

● holes made in the rubber jacket of the cable close themselves and revert to the type of protection IP67


AS-i Modules

●This diagram illustrates an active AS-i module for four connections

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●the emergency stop device is part of the emergency stop function system of the machine

Emergency stop & Emergency switching off



Emergency StopEmergency Switching Off

Eliminate the risk induced by the machine operation

- Safety risk assessment -

Eliminate the risk of electrical shock by

switching off the electrical supply

Machinery

EN/IEC 60204-1

Safety of machinery

EN/ISO 13850Emergency Stop Equipment

TRIGGER


●What is an emergency stop operation● Is « an emergency operation intended to stop a process or a movement

that has become hazardous » is part of the emergency stop function system of the machine

●What is an emergency switching off operation● Is « an emergency operation intended to switch off the supply of

electrical energy to all or part of an installation where a risk of electric shock or another risk of electrical origin is involved »

is directly linked to risk of electrical origin, related to the machine or not



Trigger action & non trigger action

●What is a « Trigger action » product● When the operator is pushing the mushroom head (actuator), the head is

translating to a position where, even if the action on the actuator is discontinued, the mechanism will continue automatically its translation, switch the associated contacts and generate the emergency stop command + the latching-in of the device.

as soon as the NC contact starts to become open, the product will latch in the open

position even if you stop to push on the head, or pull the cable.

●What is a « non-trigger action » product● When the operator is pushing on the mushroom head (actuator) up to the

mechanical stop (over travel), switch the associated contacts and automatically latch-in.

when the contact is open and the head is not in its « latching » position, the fact to stop to

push on the head or pull on the cable will close the NC contact again. it is consequently necessary to push on the head up to its latching point to guarantee and maintain the opening status of the NC contact.


Zoom on solutions

●In Machinery it is obligatory to use an Emergency Stop with Trigger function and circular yellow legend

●However, in Building sector there are no restrictions on use of the trigger or non-trigger E-stops

MachineryBuilding

Emergency Stopor

Emergency

Switching offfunction

Emergency

Switching offfunction

EMERGENCY

STOP

EMERGENCY

SWITCHING OFF

++TRIGGER

TRIGGER or

Non-TRIGGER

=


Emergency Stop Trip-wire

● An e-stop trip wire switch is designed to be triggered by a single human action when a normal e-stop function cannot be used

● This applies to:● Long installations ● Situations where operations are necessary

around the machine

● It is used to transmit a stop command:● At any point in the work zone ● Regardless of the direction in which the wire is

activated

● These components conform with standard EN/ISO 13850:2006

Three essential principles:● Positive operation● Latching● Resetting


XY2 CH

● Simple to install

Direct mounting of cable with integral tensioner

Mechanical indication of the cable tension

Only 2 screws to attach the cover

● Simple to use

Visual indication of safety contact

ON

OFF Option: Yellow beacon

with incandescent bulb

24V

48V

130

V

230

V Low operating force


Anchor point to the left

XY2 CE

● Simple to install

Reset device

Optional window for cable tension indication

Polychloroprene

or silicon (for low temperatures) bellows

Anchor point to the right

Optional indicator light with incorporated incandescent bulb to show state of contacts

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Two-hand Control Station

●It requires simultaneous operation by both hands inorder to start and maintain operation of a machine.It therefore provides protection exclusively for the person operating it.

●The control station can be mounted:● directly on the machine housing

● on a pedestal, enabling 3 directional adjustment:●height●rake●skew

●Two-hand control station can be operated differently

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Enabling Switch

●Enabling switches, allow authorised personnel to carry out maintenance, adjustment or programming operations within hazardous zones of machines, provided certain conditions are met

●Operating principle - The three possible states are:

● position 0: contact open(control operator at rest)

● position 1: contact closed(control operator depressed to

normal enabling position)

● position 2: contact open (controloperator fully depressed)

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Foot Switch

●Foot switches are an ideal solution for providing start and stop instructions for many types of industrial machines, running in various operating modes

●Additional protection and safety possibilities:● The cover avoids the risk of accidental starting

resulting from a human action or falling object

●Positive action is required on the toe plate 1 before

the pedal 2 can be depressed to start the machine

● Can be mounted directly on the baseplate of the pedestal XY2 for two-hand control stations

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Switch Disconnectors

● Mini-Vario and Vario rotary switch disconnectors from 12 to 175A

● Used for equipment isolation from electrical supply and disconnection (interrupt current running through equipment)

● Can be safely used for «on-load» making and braking of circuits

● Pad-lockable handle in the Open position

● They does not include any protection mechanism

● May be used as an Emergency Stop button (with yellow cover and red handle)

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Standards

How to obtain CE marking?!


Directives and Standards

●European Directives are mandatory● must be translated locally and applied within two years from publication;

● define the "essential requirements", e.g. protection of health and safety requirements, that product must meet before placed on the European market

●Standards are not mandatory, ● unless they are mentioned in a legislative text on the country level

●The European standards bodies are mandated to draw up the technical specifications (Harmonized Standards) meeting the requirements of the Directives

●Comply with the Harmonized Standards is the simplest way to comply with the Machinery Directive


Standardization Institutes

OSHA

ANSI

IEC (electrical standards)

ISO (other standards: mechanical parts...)

CEN (mechanical standards)

CENELEC (electrical standards)

JIS

BSDIN

CEI

SAA

UNE

GOST

NFCSA

UL

SIS

ISO: International Organization for StandardizationIEC: International Electrotechnical Commission CEN: Comité Européen de NormalisationCENELEC: Comité Européen de Normalisation Electrotechnique

(PCB making machines)


Standardization Bodies

●All countries use IEC and ISO standards or adapt them locally. ●All the main institutes work jointly with other international organizations.


European Standard’s Subordination

A basic std

EN ISO 12100Fundamental notions,Design main principles

EN 693hydraulic Presses

EN 692Mechanical presses

C specific class of machines

EN 1088Locking devices

EN 953Fixed and mobile protectors

EN/ISO 13850:2006Emergency

Stop equipment

EN 574Bi-manual

command devices

B2 safety devices

EN 1050 = EN/ISO 14121Risk assessment

EN 954-1 = ISO 13849-1:1999 EN ISO 13849Safety of machinerySafety-related part of ctrl sys

EN 60 204-1Machines electrical

equipment

EN 294 and 999Safety distances

B1 specific safety aspect


European Machinery Directive 98/37/EC

● European Machinery Directive, an early example of the “New Approach” to technical harmonisation and standardisation for products, relies on:

mandatory essential health and safety requirements (which must be met before machinery is placed on the market)

voluntary harmonised standards drawn up by the European Committees for Standardisation (CEN) and Electro-technical Standardisation (Cenelec)

conformity assessment procedures tailored to the type and level of risks associated with machinery and,

the CE marking, affixed by manufacturers to signify compliance with all relevant directives. Machinery bearing this marking may circulate freely within the European Economic Area

● A new version of the Machinery Directive 2006/42/EC will be effective in November 2009

● At the moment both versions are valid

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Basic concepts

●According to the requirements of standard EN/ISO 12100-1, the machine designer’s job is to reduce all risks to a value lower than the acceptable risk

● It gives guidelines for the selection and installation of devices which

can be used to protect persons and identifies those measures that are implemented by the machine designer and those dependent on its user

●This standard recognises two sources of hazardous phenomena:● moving parts of machines● moving tools and/or workpieces

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●Machines are sources of potential risk and the Machinery Directive requires a risk assessment to ensure that any potential risk is reduced to less than the acceptable risk

●Risk assessment consists of a series of logic steps which make it possible to systematically analyse and evaluate machinery-related risks

●Risk assessment steps:● Identification of the potential hazard● Risk estimation● Risk evaluation

●EN/ISO 13849-1 => Performance Level (PL)●EN/IEC 62061 => Safety Integrity Level (SIL)

● Risk reduction

Risk Assessment Principles

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Risk Evaluation

●On the basis of the risk assessment, the designer has to define the safety related control system. To achieve that, the designer will chose one of the two standards appropriate to the application:

● either standard EN/ISO 13849-1, which defines performance levels (PL)

● or standard EN/IEC 62061, which defines safety integrity levels (SIL)

●The table below gives relations between these two definitions

●To select the applicable standard, a common table in both standards gives indications:

-

(1) For designated architectures only

d


Remark: Change of Standards

● The qualitative approach of the EN 954-1 is no longer sufficient for modern controls based on new technologies (Electronic and Programmable Electronic systems):

● insufficient requirements for programmable products,● The reliability of the components is not taken into account,● too deterministic orientation (designated architectures).

● Standard EN ISO 13849-1 will totally replace the EN 954-1 in November 2009, and will upgrade the qualitative approach by the new quantitative (probabilistic) approach and is consistent with safety standards in general.

● At the moment both standards EN 954-1 and EN/ISO 13849-1 are valid

● For complex machines using programmable systems for safety-related control, the sector specific standard EN/IEC 62061 has to be considered

● EN/IEC 62061 based on EN/IEC 61508


Standard EN/IEC 62061

●Specific to the machine sector within the framework of EN/IEC 61508:● gives rules for the integration of safety-related electrical, electronic and

electronic programmable control systems (SRECS)

● does not specify the operating requirements of non-electrical control components in machine (ex.: hydraulic, pneumatic)

●The probability of failure associated to the required SIL (Safety Integrity Level) depends on the frequency of usage of the safety function to be performed

Safety of Machineryapplication

EN/IEC 62061back


Standard EN/ISO 13849-1

●The Standard gives safety requirements for the design and integration of safety-related parts of control systems, including software design.

●The Risk Graph helps to determine the required PL (Performance Level) of each safety function

● S - Severity of injury

>S1 Slight injury

>S2 Serious or permanent injury or death

● F - Frequency and / or exposure to a hazard

>F1 Seldom to less often and / or short time

>F2 Frequent to continuous and / or long time

● P - Possibility of avoiding the hazard or limiting the harm

>P1 Possible under specific conditions

>P2 Scarcely possible


Relationship Between Different Criteria

●Relationship between Categories, DCavg, MTTFd and PL

*In several application the realisation

of performance level c by category 1

may not be sufficient. In this case a

higher category e.g. 2 or 3 should

be chosen.

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●Standard EN/IEC 60204-1 completes the safety standards by giving setting-up rules for each component of a machine’s electrical functions.

It specifies, amongst other things:● the type of connection terminals and disconnection and breaking devices,

● the type of electric shock protection,

● the type of control circuits,

● the type of conductors and wiring rules,

● the type of motor protection.

Electrical Equipment ofMachines

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● Schneider Electric wants to support the customers of PREVENTA safety products in order to achieve easily the certification of their machines.

● There are 6 steps in the process of certification and CE marking of machines:

1. Applying all relevant directives and standards

2. Complying to the essential health and safety requirements

3. Draw up the technical documentation

4. CE-Type-examination (if applicable proceed with the conformity examination)

5. Draw up the Declaration of Conformity

6. Affix the CE marking

● Anyway for all machines listed in annex IV the customer needs a document from the notified body before affixing the CE mark on the machine

Summary: 6 steps to getthe “passport”


Recommendations

●Today there are 575 harmonised standards under the machinery directive, and out of that we find about 350 standards for machines. Nevertheless there are only a few harmonised standards for the machines listed in annex IV.

● In order to ensure the adequate consideration of all applicable standards it is advisable to have made a CE Type-Examination.

●Specially in all cases where an CE Type-Examination is made, the Notified Body should be involved from the beginning of the project in order to detect discrepancies as early as possible during the development phase and also in order to achieve the certification as soon as possible at the end of the project.

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Safety Principles

Focus on basic safety concept


Positive Opening Operation●The achievement of contact separation as the direct result of a

specified movement of the switch actuator through non-resilient members

●Safety switches employ a rigid mechanical link from the actuator to open Normally Closed contacts. The normal operation of the switch will force apart contacts, even those that are welded shut. For more information see ISO14119 and IEC 60947-5-1


Operation in Negative Mode

●In case of welded contacts or broken spring contacts stays in the closed position, which may result on the safety of machine and personnel


Combined Mode

●To clear faults due to positive mode, use combined mode


Mechanically Linked Electrical Contacts

●Mechanical guiding (forced guiding) makes it impossible to close the normally closed and normally open contacts simultaneously

● If a failure occurs: contact A welded; then contact B stays open.


Locking and Interlocking Devices

●Stops the machine and allow immediate access as soon as the access request is detected

● XCS-MP, XCS-M, XCS-TA, XCS-PA, etc.

●Allow access to the machine only after

it’s complete stop● XCS-TE, XCS-E, XCS-B /C, etc.

Interlockingdevices with

locking function

Interlockingdevices

Monitoring device

Normalapproach

Dangerzone

S

Access time = Time to cover distance S

Stopping time < access time

Stopping time > access time


Mirror Contacts

●An electrical auxiliary contact mechanically linked to the power poles is an N/C auxiliary contact which can never be closed at the same time as the power poles

● If one of the power pole contacts

becomes welded, the mechanical

link prevents the N/C auxiliary

contact from closing when the coil

is de-energised


Redundancy and Self-monitoring

Consists of compensating for the failure of one component by correct operation of another, based on the assumption that

both will not fail simultaneously

Consists of automatically checking the operation of each of the components which change state at each cycle

Redundancy Self-monitoring


Redundancy + Self-monitoring

= the risk of not operating safely is hardly reduced down to an acceptable level compared to the consequences

An initial fault in the safety circuit is detected before a second fault occurs (next cycle inhibited)

Redundancy Self-monitoring

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T hanksfor your attention

Documents

Machine Safety Training for Beginners Introduction to Machine Safety