2. Technical specificationsSafety instructions for electrical drives and controllers
Festo.P.BE-CMMS-ST-HW-EN 0903b
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2.4.4
Protection by low voltage (PELV) against electric shock
All connections and terminals with voltages from 5 to 60 volts on the stepping motor
controller are PELVs which are designed to be safe to touch in accordance with the
following standards:
Standards
-
international: IEC 60364-4-41
-
European countries in the EU: EN 50178/1998, section 5.2.8.1.
Warning
DANGER!
High electric voltage resulting from incorrect connection!
Mortal danger, danger of injury from electric shock.
Devices, electrical components and cables may only be connected to connections and
terminals from 0 to 60 V, providing they have protective low voltage (PELV = Protective
Extra Low Voltage).
Connect only voltages and current circuits which have reliable separation of dangerous
voltages. Such separation is achieved e.g. with isolating transformers, reliable
optocouplers or battery operation separate from the mains network.
2.4.5
Protection against dangerous movements
Dangerous movements can be caused by incorrect control of connected motors.
There are various causes:
Causes
-
Unsafe or faulty circuitry or cabling
-
Faults in operating the components
-
Faults in the measured value and signal generators
-
Faults or non-EMC-compliant components
-
Faults in the software in the higher-order control system
-
Removal of end-stage enable
These faults can occur immediately after the device is switched on or after an uncertain
period of operation.
The monitoring functions in the drive components exclude to a large extent the possibility
of incorrect operation of the connected drives. With regard to the protection of human
beings, especially the danger of bodily injury and/or material damage, one must not rely
on these circumstances alone. Until the fitted monitoring functions become effective, you
must reckon with at least one incorrect drive movement, the extent of which depends on
the type of control and on the operating state.
Warning
DANGER!
Dangerous movements!
Danger of injury or death, serious bodily injury or material damage.
Содержание CMMS-ST-C8-7
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