Sls With Speed Below The Monitored Speed - ABB ACS880-07 User Manual

18 Option description
the SSE function activates the drive Safe torque off (STO) function either immediately or
after a deceleration ramp. The motor coasts to a stop or decelerates to zero speed.
There are four separate SLS functions in the FSO module with different parameter settings.
The SLS1 function is used as an example and in the delivered default settings of the +Q965
option.
For more information, see chapter Parameter settings and FSO-21 safety functions module
user's manual (3AXD50000015614 [English]).

SLS with speed below the monitored speed

This time scheme diagram illustrates the operation of the SLS function. The motor speed
is below the monitored speed when the user activates the SLS function.
Motor speed
A
B
D
1 2
A Safety function response time
B SLS1 limit positive (parameter 200.23)
C SLS1 trip limit positive (parameter SLSx.14)
D Zero speed with encoder (parameter FSOGEN.52). Relevant only if 2b occurs.
1. The user or a PLC activates the SLS request of the FSO module, that is, switches the
digital inputs of the FSO module from 1 to 0.
2. After the safety function response time (A), the FSO module starts to monitor the motor
speed. The FSO module energizes the digital output that indicates the SLS status.
(From (2) to (3)) The drive limits the motor speed so that it stays at or below the SLS1
limit positive. The FSO module monitors the actual motor speed.
(2b) If the motor speed still goes above the SLS1 trip limit positive (C), the FSO module
activates the SSE function and the motor coasts to a stop (in this case, the SSE function
has been configured as "Immediate STO", see section Parameters for the SSE function).
Note: In this case, the FSO activates the SLS indication when the motor speed goes
below the SLS1 limit positive (B).
Note: In the +Q978 option, the SBC function is used to control the main
contactor/breaker. If you have this option in the drive, the main contactor/breaker is
opened if the SLS trip limit is reached.
2b
3b
C
Time
3
SLS request
SLS status &
indication