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5.5.2
Compensation of acceleration torque
The torque of the drive required for acceleration is defined by the moment of inertia of the system
which is made up of a constant and a diameter-dependent component.
The torque is determined “experimentally” after setting the parameters mentioned before, with deac-
tivated speed controller (limitation of speed to 0).
5.5.2.1
Compensation of constant acceleration torque
For compensation of the constant component of the acceleration, a mechanical time constant is set in
[ms] in Parameter
Mech. Time Constant at Dmin
870
. This is the time the drive needs (at rated
torque) to accelerate the empty winder to rated speed.
Parameter
Unit
Setting range
Default settings
No.
Identifier
870
Mech. Time Constant at Dmin
ms
0 .. 60000
0
Adjustment Parameter 870
•
To identify and verify the value, accelerate the empty winder.
•
First, set Parameter
Mech. Time Constant at Dmin
870
to the minimum value.
•
The frequency ramp is to be set to the highest value occurring in operation at which the output
figure of the speed controller is not yet limited.
•
Set Parameter
Minimum Deviation for Comp. Acceleration
869
(see Chapter 5.5.2.3 “Limit for
detection of acceleration process”) to 50% of the set acceleration ramp. In this way, it is ensured
that the acceleration pre-control becomes active.
•
Increase Parameter
Mech. Time Constant at Dmin
870
until the time is reached which the drive
needs (at rated torque) to accelerate the empty winder to rated speed.
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ACU
Winding Drive
37
5.5.2.2
Compensation of diameter-dependent acceleration torque
In addition to the constant component of the moment of inertia, there is a component which depends
on the current winder diameter. It increases proportionally to the fourth degree of the diameter and
reaches its maximum at maximum diameter. This component is considered by setting Parameter
Mech. Time Constant at Dmax
871
.
Parameter
Unit
Setting range
Default settings
No.
Identifier
871
Mech. Time Constant at Dmax
ms
0 .. 60000
0
This Parameter is set like Parameter
870
, the following requirements must be met:
•
To identify and verify the value, accelerate the winder with maximum diameter.
•
Note the setting of Parameter
870
, and reset it to 0.
•
Reset the Diameter Calculator to the maximum diameter by the digital signal selected in Parame-
ter
Reset Dact to Dmax
890
, see Chapter 0 “
•
Parameters for Operation Mode 10 – Estimation”.
Compensation via Parameter 871
−
The function is only useful if the mass density of the winding material does not
change (i.e. when the same material is wound up).
−
The maximum diameter is limited internally to
Dmax
888
.
•
First, set Parameter
Mech. Time Constant at Dmax
871
to the minimum value.
•
The frequency ramp is to be set to the highest value occurring in operation at which the output
figure of the speed controller is not yet limited.
•
Set Parameter
Minimum Deviation for Comp. Acceleration
869
(see Chapter 5.5.2.3 “Limit for
detection of acceleration process”) to 50% of the set acceleration ramp. In this way, it is ensured
that the acceleration pre-control becomes active.
•
Increase Parameter
Mech. Time Constant at Dmax
871
until the time is reached which the drive
needs (at rated torque) to accelerate the full winder to rated speed.
The value determined for Parameter
871
must be higher than the value set for Param-
eter
870
.
•
After setting Parameter
871
, reset Parameter
870
to the value determined before.
•
Test if the drive works with maximum diameter like before.
38
ACU
Winding Drive
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