Summary
Preface
P. 6
Chapter 2
P. 17
Technical data
Chapter 5
P. 76
Reception, storage
and installation
Chapter 4
P. 54
General information
Chapter 3
P. 47
Application notes
Chapter 6
P. 115
Options
Chapter 7
P. 129
Preventive maintenance
Chapter 1
P. 15
Overview
and installation diagram
Answer Drives 1000
123
6
6.5.1 FIELD OF APPLICATION
The STO safety function is designed to ensure the “SAFE TORQUE OFF”
with asynchronous motors supplied by drive. If this function is active, in
fact, the motor connected to the drive is no longer powered.
The safety function is activated by two independent channels of different
technology.
A first channel, via a safety relay, off the power of the electronic devices
(drivers, photocouplers, optical fibres, buffers) that send the control
pulses to the power section and in these conditions, even if the control
electronics should generate command pulse, the power unit could no
longer move the connected motor.
A second channel inhibits both the generation of the pulses by the
microprocessor and their propagation to the control part.
The safety relay (RL1) has two contacts, one closing and one opening,
mechanically connected to each other in such a way that also the fault
status (e.g. welded contacts for closing and/or opening) cannot be closed
or open at the same time. The NO (Normally Open) contact feeds the
drivers and the NC (Normally Closed) acts as a signalling of the safety STO
status by an external system.
The activation status of the second channel is signalled via a digital output
of the microswitch that controls the relay RL2.
6.5.2 SAFETY FUNCTIONS AND RELATED LEVEL
The “STO” safety function is designed to prevent an unexpected motor
starting. A motor stopped through the “STO” safety function can be put in
the “SAFE TORQUE OFF” status. In this condition, even without electrical
isolation between the motor and drive or between the network and the
drive it is possible to perform mechanical work on the drive.
CAUTION!
• The terminals of the motor in the “SAFE TORQUE OFF” status are not
isolated from the network and can be under hazardous voltage!
• The “STO” is expected to prevent the unexpected motor start-up,
not to carry out the stop procedure: if activated with the motor rotation
determines an uncontrolled stop. If an uncontrolled stop is not desired, it
will be necessary, before activating the “STO”, to make a stop sequence.
The motor in the “SAFE TORQUE OFF” mode cannot generate torque.
To ensure the blocking of the rotation with the load torque applied to
the axis it is necessary to provide a mechanical brake.
6.5.1 FIELD OF APPLICA
TION - 6.5.2
Содержание AD1A008FBBNH
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