Settings
Setting
Meaning
Velocity tolerance
p9548
During the down ramp, the converter continually adds the speed tolerance to
the actual speed. The converter reduces the monitoring threshold until the
"Shutdown speed" has been reached.
● If the speed temporarily increases, the monitoring threshold remains at
the last value.
● If the drive accelerates by the velocity tolerance, then SAM identifies this,
and a STOP A is initiated.
Calculation
● The following applies when parameterizing the SAM tolerance:
– The maximum speed increase after SS1 or SS2 is triggered results
from the effective acceleration (a) and the duration of the acceleration
phase.
– The duration of the acceleration phase is equivalent to one monitor‐
ing clock cycle (delay from detecting an SS1/SS2 until n
set
= 0):
● Calculating the velocity tolerance:
Actual speed for SAM = acceleration × acceleration duration
The following setting rule is obtained:
– For linear axes:
SAM tolerance [mm/min] = a [m/s
2
] x MC [s] x 1000 [mm/m] x 60 [s/
min]
– For rotary axes:
SAM tolerance [rpm] = a [rev/s
2
] x MC [s] x 60 [s/min]
● Recommendation
The SAM tolerance value entered should be approx. 20 % higher than
the calculated value.
● With the tolerance, the "overshoot", which is automatically obtained
when reaching standstill when braking along the OFF3 ramp, must be
tolerated. However, it cannot be calculated as to just how high this is.
Shutdown speed acceleration monitoring
p9568
Sets the speed limit for the "SAM" and "SBR" functions.
SAM is deactivated once the set velocity limit has been fallen below. SBR is
deactivated if the safe braking ramp falls below the set speed limit.
Ramp-down time (OFF3)
p1135[0]
Sets the ramp down time from the maximum velocity or maximum speed to
standstill for the OFF3 command.
This time can be exceeded if the maximum the DC link voltage is reached.
Maximum velocity or maximum speed
(linear axis or rotary axis/spindle)
p1082[0]
Sets the highest possible velocity or speed.
Commissioning and configuring
6.6 Configuring safety functions integrated in the drive
Safety Integrated (with SINAMICS S120)
Commissioning Manual, 02/2020, A5E46305916B AB
279
