1 Scope
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 3.26.1 "interlocking device", 3.25.4 "interlocking guard" and 3.25.5 "interlocking device with guard locking" of GB/T 15706.1-2007).
It also provides requirements specifically intended for electrical interlocking devices (see Chapter 6).
This Standard covers the parts of guards which actuate interlocking devices.
Note: The processing of the signal from the interlocking device to stop and immobilize the machine is dealt with in GB/T 16855.1.
2 Normative References
The following documents contain provisions which, through reference in this text, constitute provisions of this Standard. For dated reference, subsequent amendments to (excluding any corrigendum), or revisions of, any of these publications do not apply. However, parties to agreements based on this Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. For any undated references, the latest edition of the document referred to applies.
GB 5226.1-2008 Electrical Safety of machinery - Electrical Equipment of Machines - Part 1: General Requirements (IEC 60204-1:2005, IDT)
GB 14048.5-2008 Low-voltage Switchgear and Controlgear - Part 5-1: Control Circuit Devices and Switching Element - Electromechanical Control Circuit Devices (IEC 60947-5-1:2003, MOD)
GB/T 14048.13 Low-voltage Switchgear and Controlgear - Part 5-3: Control Circuit Devices and Switching Elements - Requirements for Proximity Devices with Defined Behaviour under Fault Conditions (PDF) (GB/T 14048.13-2006, IEC 60947-5-3:1999, IDT)
GB/T 15706.1-2007 Safety of Machinery - Basic Concepts General Principles for Design - Part 1: Basic Terminology Methodology (ISO 12100-1:2003, IDT)
GB/T 15706.2-2007 Safety of Machinery - Basic Concept General Principles for Design - Part 2: Technical Principles (ISO 12100-2:2003, IDT)
GB/T 16855.1 Safety of Machinery - Safety-related Parts of Control Systems - Part 1: General Principles for Design (GB/T 16855.1-2008, ISO 13849-1:2006, IDT)
GB/T 16856.1 Safety of Machinery - Risk Assessment - Part 1: Principles (GB/T 16856.1-2008, ISO 14121-1:2007, IDT)
GB/T 19670 Safety of Machinery - Prevention of Unexpected Start-up (GB/T 19670-2005, ISO 14118:2000, MOD)
GB 23821 Safety of Machinery - Safety Distances to Prevent Danger Zones Being Reached by the Lower Limbs (GB 23821-2009, ISO 13857:2008, IDT)
IEC 62061 Safety of Machinery - Functional Safety of Safety-related Electrical, Electronic and Programmable Electronic Control Systems
3 Terminologies and Definitions
For the purposes of this Standard, the following terminologies and definitions apply:
3.1
Interlocking device
Interlock
Mechanical, electrical or other type of device, the purpose of which is to prevent the operation of hazardous machine elements under specified conditions (generally as long as a guard is not closed).
[see GB/T 15706.1-2007, 3.26.1]
3.2
Interlocking guard
Guard associated with an interlocking device, used together with machine control system to achieve the following functions:
- the hazardous machine functions "covered" by the guard cannot operate until the guard is closed;
- if the guard is opened while the hazardous machine functions are operating, a stop instruction is given;
- when the guard is closed, the hazardous machine functions "covered" by the guard can operate, but the closure and locking of the guard do not by themselves initiate their operation.
[see GB/T 15706.1-2007, 3.25.4]
3.3
Interlocking guard with guard locking
Guard associated with an interlocking device and a guard locking device, used together with machine control system to achieve the following functions:
- the hazardous machine functions "covered" by the guard cannot operate until the guard is closed and locked;
- the guard remains closed and locked until the risk of injury from the hazardous machine functions "covered" by the guard has passed;
- when the guard is closed and locked, the hazardous machine functions "covered" by the guard can operate, but the closure and locking of the guard do not by themselves initiate their operation.
[see GB/T 15706.1-2007, 3.25.5]
3.4
Guard locking device
Foreword i
Introduction ii
1 Scope
2 Normative References
3 Terminologies and 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 Device
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 (see 3.4 and 4.2.2)
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 GB 5226.1
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
Appendix A (Informative) Guard-operated Interlocking Device With One Cam-operated Position Detector (See Introduction)
Appendix B (Informative) Guard-operated Interlocking Device with Tongue-operated Switch (See Introduction)
Appendix C (Informative) Direct (Mechanical) Interlocking Between Guard and Start/Stop Manual Control (See Introduction)
Appendix D (Informative) Captive-key Interlocking Device (See Introduction)
Appendix E (Informative) Trapped-key Interlocking Device (See Introduction)
Appendix F (Informative) Plug and Socket Interlocking Device (Plug/Socket Combination) (See Introduction)
Appendix G (Informative) Guard-operated Interlocking Device Incorporating Two Cam-operated Position Detectors (See Introduction)
Appendix H (Informative) Mechanical Interlocking Between a Guard and a Movable Element (See Introduction)
Appendix I (Informative) Electrical Interlocking Device Incorporating Magnetically Actuated
(Magnetic) Switches (See Introduction)
Appendix J (Informative) Electrical Interlocking Device Incorporating Two Proximity Detectors (See Introduction)
Appendix K (Informative) Pneumatic/Hydraulic Interlocking Devices (See Introduction)
Appendix L (Informative) Interlocking Device with Spring-applied/Power-released Guard Locking Device
Appendix M (Informative) Interlocking Device with Guard Locking, with Manually Operated Delay Device
Bibliography
