KEB COMBIVERT G6, Safety Manual

Page: 10 / 24

GB - 10
Safety Function STO
Electric
Shock
Continue mains voltage with active STO function.
Compared to the disconnection by line contactors or motor contactors the integrated safety
function enables a simple integration of drives to functional groups of a system. Thereby safe
torque off can be limited to certain systems. A further advantage is that the recharge and dis-
charge time of the inverter DC link must not be considered. Thus the unit is faster again ready
for operation after an interruption.
Regular electromechanical equipment are liable to abrasion. Loss of these equipment occurs
by using the STO function and the maintenance costs are reduced.
Characteristic data for „Safe torque off“
• Power supply for the rotation direction of the motor is interrupted (free-wheeling motor)
• Used when monitoring of standstill is not necessary
• Unintentional starting of the motor is prevented
• No galvanic isolation of the motor from the inverter DC link
What is realized by the STO function related to EN 60204 ?
Emergency stop can be realized by the STO function, since the mains voltage may remain
effective.
Emergency stop can be realized only in connection with a line contactor, which disconnects
the mains voltage !
2.1 Emergency stop according EN 60204
By using suitable safety switchgear units, stop category 0 and 1 according to EN 60204 can
be reached by the STO function in the system. Note chapter 6 for safety switchgear units.
Stop category 0
„uncontrolled stop“, i.e. stop by immediate removal of power to the
actuators.
Stop category 1
„controlled stop“, i.e. power to the actuators is retained to apply
braking until the stop is achieved. The energy is switched off at
standstill.
Emergency stop to EN 60204 must be functional in all operating modes of the drive module.
The reset of emergency stop may not lead to an uncontrolled start of the drive.
Restart only
after confir-
mation
The drive restarts if function STO is no longer released. In order
to comply with EN 60204, it must be ensured by external meas-
ures that the drive restarts only after confirmation.
Without mechanical brake the drive leads to coast; motor is free-wheeling. Additional protec-
tive devices must be installed (e.g.locking systems) if damage to persons or property can
occur.
Ensure coast
of the motor
If danger to persons occur after switching off the motor control
by STO, the entrance to hazard areas must remain closed until
the drive stops.