Operation Principle - ABB ACS880-07 User Manual

20 Option description
Note: The option +Q978 uses the Safe brake control (SBC) function of the FSO module to
control the main contactor/breaker. If you use this option, you cannot use the FSO module
to control a mechanical brake.
Note: In the option +Q978, the drive STO function is used together with the SBC function
of the FSO module, which controls the main contactor/breaker. Thus, every time the drive
STO is opened also the main contactor/breaker is opened. For example, if the Safely-limited
speed (SLS) function (option +Q965) is included in the drive, the main contactor/breaker is
opened after trip limit hits. For more information, see Safely-limited speed with the encoder
interface (option +Q965) for ACS880-07/07LC/17/17LC/37/37LC drives user's manual
(3AXD50000019727 [English]).

Operation principle

The operation and configuration of the emergency stop function is slightly different with and
without a safety encoder. Only the FSO-21 module supports the safety encoder interface,
and you can also use it without a safety encoder.
Note: The Emergency stop, stop category 1 function uses the SS1 function of the FSO
module. The SS1 function uses SAR1 parameters to define the stop ramp. In some situations
(for example, in internal fault situations or due to another safety function) the FSO module
can activate the Safe stop emergency (SSE) function. The SSE function uses SAR0
parameters to define the stop ramp.
Note: If the FSO module activates the SSE function while the SS1 function is active, the
SSE function overrides the SS1 function. Therefore, SAR0 parameters are used instead of
SAR1 parameters to define the stop ramp. You must take this into account when you use
the SS1 function to implement an emergency stop (stop category 1).