Lenze 8400 motec - Manual (Page 232)

7 Technology applications
7.3 TA "Actuating drive speed (AC Drive Profile)"
232 Lenze · 8400 motec · Reference manual · DMS 4.1 EN · 08/2013 · TD05
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7.3.2 Scaling of the speed and torque values (Ref from Net)
Scaling of the speed values
On the bus side, the speed setpoint is defined in [rpm]. In the controller, however, all speed-related
signals are processed in percentage with regard to a reference variable ( C00011 ). For the scaling
required in this case, the LS_Convert_1 system bus is used (see also Internal signal flow ).
• The type of conversion can be adapted in C01354/2 .
• A conversion of [rpm] to [%] is preset for the "AC Drive Profile" application according to the
following formula.
• Optionally, an additional scaling can be executed via a scaling factor adjustable in C01353/1 .
For the output of the actual speed value to the bus, the following conversion is made:

Note!
The scaling parameterisable via C01353/1 is carried out as "Shift Operation". Overflows
are not absorbed!
Equation for scaling the speed setpoint
Parameter Name Description
C00011 Appl.: Reference speed Reference variable for speed-related signals
C01353/1 ACDrive: Speed scaling Scaling factor (-128 ... 127)
• In the Lenze setting "0", no scaling takes place (2 0 = 1)
Arithmetic example
Assumption:
• Reference speed ( C00011 ) = 2000 rpm
• Speed setpoint selection via bus = 500 rpm (≡ 25 % of the reference speed)
Conversion of the internal scaling (16384 ≡ 100 %) in percentage:
Equation for scaling the actual speed value
Parameter Name Description
C00011 Appl.: Reference speed Reference variable for speed-related signals
C01353/1 ACDrive: Speed scaling Scaling factor (-128 ... 127)
• In the Lenze setting "0", no scaling takes place (2 0 = 1)
Speed setpoint
Application
Speed setpoint
Bus
[rpm]
16384
Reference speed [rpm]
----------------------------------------------------------
1
2 Scaling factor
-------------------------------- ⋅ ⋅ =
Speed setpoint
Application
500[rpm]
16384
2000 [rpm]
----------------------------- 1
2 0
------ ⋅ ⋅ 4096 = =
4096 100 [%]
16384
------------------- ⋅ 25 [%] (of C00011) =
Actual speed value
Bus
[rpm] Actual speed value
Application
Reference speed [rpm]
16384
---------------------------------------------------------- 2 Scaling factor
⋅ ⋅ =