ABB FSO-21, User Manual

Page: 109 / 540

Safety functions 109
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SSE with immediate STO, SBC after STO
The operation of the SSE with immediate STO, SBC after STO (positive SBC delay)
is described in the time diagrams and tables below. For configuration, see section
How to configure SSE with immediate STO, SBC after or before STO on page 353 .
Without an encoder
A SBC delay (parameter SBC.12 ): Time from the activation of the drive STO function to the
moment when the FSO activates the SBC function (brake). In this case, the value is
positive and the FSO activates the SBC after the drive STO. If the value is zero, the FSO
activates the SBC and drive STO functions at the same time.
Note : It is possible to set
the SBC delay so that the SBC is activated while the motor is still rotating.
B SBC time to zero speed (parameter SBC.13 ): Time from the SBC activation to the
moment when the safety function is completed and the SSE completed indication
(parameter
SSE.22 ) goes on. The acknowledgment becomes allowed. You must set this
to the estimated time in which the motor brakes to a stop from the maximum speed.
Drive STO state
& indication
SSE request
Motor speed
Time
SSE completed
indication
1 4
A
2
SBC output
B
5
3
SBC.12
SBC.13
SSE state &
indication