Time Schemes With A Speed Estimate (No Safety Encoder); Emergency Stop, Stop Category 0 - ABB ACS880-07 User Manual

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Time schemes with a speed estimate (no safety encoder)

Emergency stop, stop category 0

This time scheme diagram illustrates the operation of the Emergency stop, stop category
0 safety function. This option uses the Safe torque off (STO) function of the FSO module.
Motor speed
STO.13
B
1
A SBC time to zero speed: Time from the activation of the STO function to the moment when
the STO completed indication becomes active and the indication lamp comes on. The user
must set this time longer than the time the motor coasts from the maximum speed to zero
speed (parameter SBC.13 SBC time to zero speed).
B Restart delay: Delay from pushing the emergency stop button (and activation of the STO
function) to the moment when the user can push the reset button at the earliest (and acknow-
ledge the STO function). With this parameter, it is possible to allow a restart of the drive while
the motor is still running (fly-start) (parameter STO.13 Restart delay after STO).
1. The user pushes the emergency stop button. The FSO module activates the FSO and
drive STO functions and opens the main contactor/breaker. The FSO module starts
timers for delays A and B.
2. The user releases the emergency stop button.
3. Time B elapsed. The user can push the reset button, that is, the acknowledgement of
the STO function is possible.
4. Time A has elapsed. The emergency stop indication lamp comes on.
5. The user pushes the reset button (this resets the emergency stop circuit and
acknowledges the STO function).
6. The FSO module deactivates the STO function in the drive and closes the main
contactor/breaker. The emergency stop indication lamp goes off. The drive is ready for
a restart.
SBC.13
A
2 3
Option description 21
4 5 6
Time
E-stop button
(STO request)
Drive STO
status
Contactor
(SBC output)
Reset button
Indication lamp