Sse With Immediate Sto - ABB FSO-21 User Manual

94 Safety functions
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SSE with immediate STO

The operation of the SSE with immediate STO function is described in the time
diagrams and tables below. For configuration, see section
immediate STO on page 284.
Without an encoder
Motor speed
1
A Time to zero speed (parameter STO.14): Time from the STO activation to the moment
when the safety function is completed, the SSE completed indication (parameter
SSE.22) goes on and the acknowledgment becomes allowed. You must set this to the
estimated time in which the motor coasts to a stop from the maximum speed.
Step Description
1 The SSE request is received (for example, from the I/O). The FSO activates the drive
STO function and starts a counter for time A.
2 After time A has elapsed, the FSO module defines the motor as stopped and the SSE
completed indication goes on. The acknowledgement becomes allowed as soon as
the SSE request has been removed (step 3).
3 The SSE request is removed.
4 After the acknowledgement, the SSE and STO functions are deactivated, and the
control is given back to the drive. The indications goes off.
STO.14
A
How to configure SSE with
4
2 3
SSE request
Drive STO state
& indication
SSE state &
indication
SSE completed
indication
Time