Siemens SINAMICS G120 Function Manual page 33

Scenario 2: The absolute value of the load speed is higher than the monitoring threshold.
● After a definable "SS1 delay" has elapsed, the inverter uses the SBR (Safe Brake Ramp)
● The inverter switches from SBR monitoring to "SLS monitoring" as soon as one of the
● When you deselect SLS, the motor continues following its speed setpoint.
Safety Integrated Function Manual, SINAMICS G120 and G120C
Function Manual, 01/2011, FW 4.4, A5E03052391B AB
function to determine whether the load speed has decreased. The delay is the same as
that for the SS1 function.
Note
Normally, the inverter brakes the motor when selecting SLS with the OFF3 ramp-down
time (parameter p1135). If you do not want that the inverter automatically brakes the
motor, then you must disconnect the interconnection between the "SLS" function and the
ramp-function generator of the inverter: p1051 = 9733 → 1083 and p1052 = 9733 → 1086.
If the motor does not automatically brake the inverter, then the machine control must
ensure that the motor speed lies below the monitoring threshold in sufficient time.
following two conditions is fulfilled:
– The SBR ramp has reached the "SLS monitoring" value.
– The load speed has decreased to the "SLS monitoring" value and the "SS1 delay" has
elapsed. This case is illustrated in the diagram below.
Figure 2-10 Selecting and deselecting the SLS safety function at high speeds
Description
2.5 Safely Limited Speed, SLS
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