Type B Group Safety Standard
Type A ISO12100 Series often refers to Type B IEC60204-1 (Safety of Machinery - Electrical Equipment of Machines - Part1: General requirements). As
IEC60204-1 is an important standard pertaining to electrical devices, a list of its requirements is provided as follows.
The numbers in brackets refer to article/sub-article numbers IEC60204-1.
■General requirements (4)
Electrical components and devices shall be suitable for their intended use and conform to relevant IEC standards where such standards exist.
■Incoming supply conductor terminations & devices for disconnecting and turning off (5)
■Protection against electric shock (6)
・Protection by enclosures (6.2.2)
At least IP2X or IPXXB is required to protect against direct physical contact with voltage. IP1X or IPXXA is required for a protective system in which
the opening of a door disconnects a voltage. IP2X or IPXXB is required for live parts having a voltage after opening the door. (Refer to IEC60529).
■Protection of equipment (7)
Protection of equipment against short circuit, overload current, ground fault, overvoltage due to lightning and switching surges, abnormal temperature; loss
of or reduction in the supply voltage; overspeed of machines/machine elements; incorrect phase sequence.
■Equipotential bonding (8)
■Control circuits and control functions (9)
●Control circuits (9.1)
・The normal voltage shall not exceed 277 V when supplied from a transformer. (9.1.2)
・Control circuits shall be provided with overcurrent protection (9.1.3)
●Control functions (9.2)
・Start functions (9.2.1)
・There are three categories of stop functions. (9.2.2)
Category 0: Stopping by removal of power (non-controlled stop)
Category 1: Controlled stop with power available to the machine actuators to stop and then removal of power when stopped (controlled stop).
Category 2: Controlled stop with power left available to the machine actuators.
・Emergency stop (9.2.5.4.2)
Emergency stop overrides all other functions and operations in all modes.
Emergency stop achieved by Category 0 or Category 1.
・Monitoring of command actions (9.2.5.5)
・Two-hand control (9.2.5.7)
Two-hand control type is selected by the risk assessment
・Enabling device (9.2.5.8)
Manually operated auxiliary control device used in conjunction with a start control. It should have the feature of connecting to a Category 0 stop or to
a Category 1 stop.
●Protective interlocks (9.3)
The closing or resetting of an interlocking safeguard shall not initiate machine motion or operation that can result in a hazardous condition.
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SAFETY CONCEPTS BOOK
■Operator interface and machine-mounted control devices (10)
●Location and positioning
Readily accessible for service and maintenance; selection and installation of actuators of hand-held control devices; colors and markings of
(illuminated) pushbutton switches; light indicators and displays; color of emergency stop pushbutton actuators (red); shape (mushroom) and
background color (yellow)
■Electronic equipment (11)
Programmable controllers (PLC) shall conform to IEC61131-1/-2.
■Control gear: location, mounting and enclosures (12)
Operation and maintenance; protection against external influences; protection against mechanical, electrical and heating effects.
■Conductors and cables (13)
Suitable for operating conditions (e.g., voltage, current, etc.); suitable for external influences (e.g., temperature, corrosive substances, mechanical stress,
fire, etc.)
■Wiring (14)
All connections shall be secured against accidental loosening.
■Electric motors and associated equipment (15)
Conformity to IEC60034-1 is desired. Provided with over-current and overload protection.
■Accessories and lighting (16)
Requirements for accessories and local lighting
■Marking, warning signs, and reference designations (17)
Durability of supplier's name (trademark), warning signs, etc.
■Technical documentation (18)
The information necessary for installation, operation, and maintenance of the electrical equipment of a machine shall be supplied in the form of drawings,
diagrams, charts, tables, and instructions
■Testing and verification (19)
General mechanical and electrical requirements
−Electrical equipment in compliance with technical documentation
−Continuity of protective bonding circuit
−Insulation resistance tests
−Voltage tests
−Protection against residual voltages
−Functional tests
SAFETY CONCEPTS BOOK
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Type B Group Safety Standard
Type B IEC60204-1 often references the requirements for opening/closing parts of components used, the requirements for programmable controllers, the
IEC60947 series, and the IEC61131 series.
IEC60947-1: Low-voltage switchgear and controlgear - Part 1: General rules
IEC60947-5-1: Low-voltage switch gear and control gear - Part 5-1: Control circuit devices and switching elements - Electromechanical control circuit devices
IEC61131 Series: Programmable Controllers
These standards define in details the structural requirements of components used (insulation distances), features (opening/closing functions), and
testing methods. Electrical components of a machine in conformity to these requirements are considered safe for use.
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SAFETY CONCEPTS BOOK