EN 1088:1995+A2:2008

Foreword
Introduction
1 Scope
2 Normative references
3 Definitions
4 Operating principles and typical forms of interlocking devices
  associated with guards
  4.1 Interlocking principles
  4.2 Typical forms of interlocking devices
  4.3 Technological forms of interlocking devices
5 Provisions for the design of interlocking devices (independent
  of the nature of the energy source)
  5.1 Actuation modes of mechanically actuated position detectors
  5.2 Arrangement and fastening of position detectors
  5.3 Arrangement and fastening of cams
  5.4 Reducing the possibility of common cause failures
  5.5 Guard locking device
  5.6 Delay devices
  5.7 Design to minimize defeat possibilities
  5.8 Environmental considerations
6 Additional technological requirements for electrical interlocking
  devices
  6.1 Compliance with EN 60204-1
  6.2 Interlocking devices incorporating mechanically actuated
      position switches
  6.3 Interlocking devices incorporating non-mechanically actuated
      position switches (proximity switches and magnetic switches)
7 Selection of an interlocking device
  7.1 General
  7.2 Conditions of use and intended use
  7.3 Risk assessment
  7.4 Stopping time and access time
  7.5 Frequency of access (frequency of opening the guard for
      access to the danger zone)
  7.6 Performance considerations
Annex A (informative) Guard-operated interlocking device with
        one single cam-operated position detector
Annex B (informative) Guard-operated interlocking device with
        tongue-operated switch
Annex C (informative) Direct (mechanical) interlocking between
        guard and start/stop manual control
Annex D (informative) Captive-key interlocking device
Annex E (informative) Trapped-key interlocking device
Annex F (informative) Plug and socket interlocking device
        [plug/socket combination]
Annex G (informative) Guard-operated interlocking device
        incorporating two cam-operated position detectors
Annex H (informative) Mechanical interlocking between a guard and
        a movable element
Annex J (informative) Electrical interlocking device incorporating
        magnetically actuated [magnetic] switches
Annex K (informative) Electrical interlocking device incorporating
        two proximity detectors
Annex L (informative) Pneumatic/hydraulic interlocking devices
Annex M (informative) Interlocking device with spring
        applied/power released guard locking device
Annex N (informative) Interlocking device with guard locking,
        with manually operated delay device
Annex ZA (informative) Relationship between this European
         Standard and the Essential Requirements of EU
         Directive 98/37/EC
Annex ZB (informative) Relationship between this European
         Standard and the Essential Requirements of EU
         Directive 2006/42/EC
Bibliography

This standard specifies principles for the design and selection - independent of the nature of the energy source - of interlocking devices associated with guards (as defined in 3.23.1 'interlocking device [interlock]', 3.22.4 'interlocking guard' and 3.22.5 'interlocking guard with guard locking' of EN 292-1). It also provides requirements specifically intended for electrical interlocking devices (see clause 6). This standard covers the parts of guards which actuate interlocking devices. Requirements for guards are given in prEN 953. The processing of the signal from the interlocking device to stop and immobilize the machine is dealt with in prEN 954-1.