Siemens SINAMICS G120 Manual page 163

p1226[0...n] Threshold for zero speed detection / n_standst n_thresh
Access level: 2
Can be changed: U, T
Units group: 3_1
Min
0.00 [rpm]
Description: Sets the speed threshold for the standstill identification.
Acts on the actual value and setpoint monitoring.
When braking with OFF1 or OFF3, when the threshold is undershot, standstill is identified.
Dependency: Refer to: p1227
Notice: For reasons relating to the compatibility to earlier firmware versions, a parameter value of zero in indices 1 to 31 is
overwritten with the parameter value in index 0 when the Control Unit boots.
Note: Standstill is identified in the following cases:
- the speed actual value falls below the speed threshold in p1226 and the time started after this in p1228 has
expired.
- the speed setpoint falls below the speed threshold in p1226 and the time started after this in p1227 has expired.
The actual value sensing is subject to measuring noise. For this reason, standstill cannot be detected if the speed
threshold is too low.
p1227 Zero speed detection monitoring time / n_standst t_monit
Access level: 3
Can be changed: U, T
Units group: -
Min
0.000 [s]
Description: Sets the monitoring time for the standstill identification.
When braking with OFF1 or OFF3, standstill is identified after this time has expired, after the setpoint speed has
fallen below p1226 (also refer to p1145).
Dependency: The parameter is pre-assigned depending on the size of the power unit.
Refer to: p1226
Notice: For p1145 > 0.0 (RFG tracking) the setpoint is not equal to zero dependent on the selected value. This can there-
fore cause the monitoring time in p1227 to be exceeded. In this case, for a driven motor, the pulses are not sup-
pressed.
Note: Standstill is identified in the following cases:
- the speed actual value falls below the speed threshold in p1226 and the time started after this in p1228 has
expired.
- the speed setpoint falls below the speed threshold in p1226 and the time started after this in p1227 has expired.
For p1227 = 300.000 s, the following applies:
Monitoring is de-activated.
For p1227 = 0.000 s, the following applies:
With OFF1 or OFF3 and a ramp-down time = 0, the pulses are immediately suppressed and the motor "coasts"
down.
Once the Control Unit has been booted up for the first time or if the factory settings have been defined accordingly,
the parameter is defined in accordance with the power unit.
© Siemens AG 2011 All Rights Reserved
SINAMICS G120 Control Units CU230P-2 Parameter Manual (LH9), 01/2011
Calculated: -
Scaling: -
Unit selection: p0505
Max
210000.00 [rpm]
Calculated: -
Scaling: -
Unit selection: -
Max
300.000 [s]
Parameters
List of Parameters
Data type: FloatingPoint32
Data set: DDS, p0180
Factory setting
20.00 [rpm]
Data type: FloatingPoint32
Data set: -
Factory setting
300.000 [s]
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