6.6
Safely Limited Speed (SLS)
6.6.1
Overview
What can you find in this Chapter?
The relevant operating cases for the SLS function are described in this chapter.
Table 6-5
Response of the SLS function when the motor is switched on (ON/OFF1 = 1)
Selecting and de‐
selecting SLS
Selecting and deselecting SLS when the motor is switched on (Page 253)
Switching over
SLS levels when
SLS is active
Switching over from a higher SLS level to a lower SLS level (and vice versa).
Switching over SLS levels (Page 260)
Discrepancy in
the input signal
The fail-safe digital input to select SS1 identifies an error.
Response to a discrepancy when SLS is active (Page 268)
Limit value viola‐
tion
The speed of the motor exceeds the set SLS limit value.
Limit value violation when SLS is active (Page 270)
Table 6-6
Switching the motor on and off when SLS is active or not active
Switching on the motor (ON/OFF1 =
0 → 1)
Switching off the motor (ON/OFF1,
OFF2 or OFF3 = 1 → 0)
SLS is not active If SLS is not active, then there are no restrictions for switching on and switching off
the motor.
SLS is active
If your application requires that SLS al‐
ways remains active, then you must take
into account several special issues when
switching on the motor.
Switching on the motor when SLS
The drive response depends on the sig‐
nal that you use to switch off the motor.
Switching off the motor when SLS
6.6.2
Selecting and deselecting SLS when the motor is switched on
Selecting SLS when the motor is switched on
As soon as the inverter detects the selection of SLS via a fail-safe digital input or via the
PROFIsafe safe communication, the following happens:
● The inverter limits the speed to a value below the SLS monitoring and brakes the motor
with the OFF3 ramp-down time.
● You can select whether the inverter monitors motor braking using the SMR (Safe Brake
Ramp) function.
Operation
6.6 Safely Limited Speed (SLS)
Safety Integrated - SINAMICS G110M, G120, G120C, G120D and SIMATIC ET 200pro FC-2
Function Manual, 01/2017, FW V4.7 SP6, A5E34261271B AD
253