WARNING
When the Safe Torque Off circuit is enabled, the motor can no longer generate torque. When external forces act on the axis
(e.g. the force of gravity on the vertical axis), adequate protection must be provided, such as an automatic mechanical
blocking system or weight equalisation system
WARNING
The Safe Torque Off function does not provide any electrical insulation. It does not provide any protection against electric
shock. The machine or complete system must be electrically insulated from the power line using the main disconnecting
device, locked in an open position, before carrying out any work on the machine or system, for example maintenance, servicing
or cleaning (see EN 60204-1: 2006, section 5.3). Personnel must be aware that the busbars may have hazardous voltages
after being turned off (capacitive voltage) and the discharge time is approximately 6 minutes
7.5. Safe Torque Off circuit
The Safe Torque Off function has been designed using redundant blocking devices that act independently of the power
module controls. The function makes it possible to keep the drive to be turned off powered, to avoid the normal re-
start procedure.
WARNING
The STO function is automatically restarted when safety inputs are enabled. The machine manufacturer is
responsible for checking and installing a manual reset function, if necessary, that prevents the motor from restarting
automatically
AVERTISSEMENT
La fonction STO est automatiquement redémarrée lorsque les entrées de sécurité sont activées. Le fabricant de la
machine est responsable de la vérification et de l'installation d'une fonction de réinitialisation manuelle, si nécessaire,
qui puisse empêcher le redémarrage automatique du moteur.
The DR2020 drive controls the movements of an AC three-phase motor by generating a rotating magnetic field. For
this purpose the microprocessor generates a complex pulse model (PWM), which are amplified and used to drive the
power semiconductors. The Safe Torque Off function of the DR2020 operates through hardware with two channels
that interrupt pulses directed to IGBT.
Two monitoring modes are provided to detect dangerous faults: the "Hardware Feedback" monitoring system shows
the operating status of the circuit; the same information is available through the system "Software Feedback"
consisting of a binary digital signal defined by the IEC 61800-7-201 standard, CIA 402 Object 60FD, (digital inputs) bit
3.
7.6. Safe Torque Off
Connection
The management channels, including the "hardware feedback" signal, of the Safe Torque Off circuit are monitored
using the X1 connector. Both monitoring channel work modes are always available; the user has the right to choose the
type of monitoring; the "Hardware feedback" type or the "Software feedback" type or both the functions at the same
time.
DR2020
MAR2-E-191
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