Parameters for configuring the scaling and limits for analog input 2 (terminal 54).
NOTE
Analog input 53 is preset for usage with “open loop”
control on 0-10 V. Terminal 54 is preset for “Process Loop”
control using a pressure sensor AKS with a pressure range of -1 : 12 bar.
6-20 Terminal 54 Low Voltage
Range: Function:
1.00V* [-10.0 - par.
6-11]
This analog input scaling value should correspond to the minimum output value of the pressure sensor 6-21 Terminal 54 High Voltage
Range: Function:
5.00V* [6-10 to 10 V] This analog input scaling value should correspond to the maximum output value of the pressure sensor.
6-22 Terminal 54 Low Current
Range: Function:
4.0mA * [0.0 to par. 6-13 mA]
This reference signal should correspond to the minimum output value of the pressure sensor.
6-23 Terminal 54 High Current
Range: Function:
20.0mA * [6-12 to 20 mA] This reference signal should correspond to the maximum output value of the pressure sensor.
6-24 Terminal 54 Low Ref./Feedb.
Range: Function:
-1 (bar) [Value] Enter the analog input scaling value that corresponds to the minimum reference feedback value set in 3-02 Minimum Reference.
6-25 Terminal 54 High Ref./Feedb.
Range: Function:
12 (bar) [Value ] Enter the analog input scaling value that corresponds to the maximum reference feedback value set in 3-03 Maximum Reference.
6-26 Terminal 54 Filter Time Constant
Range: Function:
0.001 s* [0.001 -10.000 s]
Enter the time constant. This is a first-order digital low pass filter time constant for suppressing electrical noise in terminal 54. A high time constant value improves dampening but also increases the time delay through the filter.
NOTE
This parameter cannot be adjusted while the motor is running.
6-50 Terminal 42 Output
Option: Function:
Select the function of Terminal 42 as an analog current output. Depending on the selection the output is either a 0-20 mA or 4-20 mA output. The current value can be read out in LCP in 16-65 Analog Output 42 [mA].
[0] No operation
There is no signal on the analog output.
[100] Output
3-00 Reference Range [-Max - Max] -100% = 0 mA; 0% = 10 mA; +100% = 20 mA
[103] Motor current 0-20 mA
Value is taken from 16-37 Inv. Max. Current.
Inverter max. current (160% current) is equal to 20 mA.
Example: Inverter norm current (11 kW) = 24 A. 160% = 38.4 A. Motor norm current = 22 A Read-out 11.46 mA.
20 mA x 22 A
38.4 A = 11.46 mA
In case the norm motor current is equal to 20 mA, the output setting of 6-52 Terminal 42 Output Max Scale is:
IVLTMax x 100
IMotorNorm = 38.4 x 10022 = 175 %
[104] Torque rel to lim 0-20 mA
The torque setting is related to setting in 4-16 Torque Limit Motor Mode
6
6
6-50 Terminal 42 Output
Option: Function:
[105] Torque rel to rated motor torque 0-20 mA
The torque is related to the motor torque setting.
[106] Power 0-20 mA
Taken from 1-20 Motor Power [kW].
[107] Speed 0-20 mA
Taken from 3-03 Maximum Reference. 20 mA
= value in 3-03 Maximum Reference [108] Torque ref.
0-20 mA
Torque reference related to 160% torque.
[109] Max Out Freq 0-20 mA
In relation to 4-19 Max Output Frequency.
[134] Torque%
lim. 4-20 mA
The torque setting is related to setting in 4-16 Torque Limit Motor Mode.
[135] Torque%
nom 4-20 mA
The torque setting is related to the motor torque setting.
[141] Bus ctrl.
0-20 mA, timeout
4-54 Warning Reference Low defines the behaviour of the analog output in case of bus time-out.
[142] Bus ctrl.
4-20 mA, timeout
4-54 Warning Reference Low defines the behaviour of the analog output in case of bus time-out.
[150] Max Out Freq 4-20 mA
In relation to 4-19 Max Output Frequency.
[119] Torque % lim [149] Torque %
lim 4-20mA
Analog output at zero torque = 12 mA.
Motoric torque will increase the output current to max torque limit 20 mA (set in 4-16 Torque Limit Motor Mode).
Generative torque will decrease the output to torque limit Generator Mode (set in
4-17 Torque Limit Generator Mode)
Ex: 4-16 Torque Limit Motor Mode: 200% and 4-17 Torque Limit Generator Mode: 200%. 20 mA = 200% Motoric and 4 mA = 200%
Generatoric.
0mA 4mA 12 mA 20 mA
Par 4-17
(200%) Par 4-16
(200%)
When no signal on the analog output.
[52] MCO 0-20mA
6-50 Terminal 42 Output
Option: Function:
[101] Reference 3-00 Reference Range [Min - Max] 0% = 0 mA;
100% = 20 mA
3-00 Reference Range [-Max - Max] -100% = 0 mA; 0% = 10 mA; +100% = 20 mA
[102] Feedback [103] Motor
current
Value is taken from 16-37 Inv. Max. Current.
Inverter max. current (160% current) is equal to 20 mA.
Example: Inverter norm current (11 kW) = 24 A. 160% = 38.4 A. Motor norm current = 22A Read-out 11.46 mA.
20 mA x 22 A
38.4 A = 11.46 mA
In case the norm motor current is equal to 20 mA, the output setting of 6-52 Terminal 42 Output Max Scale is:
IVLTMax x 100
IMotorNorm = 38.4 x 10022 = 175 %
[104] Torque rel to limit
The torque setting is related to setting in 4-16 Torque Limit Motor Mode
[105] Torq relate to rated
The torque is related to the motor torque setting.
[106] Power Taken from 1-20 Motor Power [kW].
[107] Speed Taken from 3-03 Maximum Reference. 20 mA
= value in 3-03 Maximum Reference [108] Torque Torque reference related to 160% torque.
[109] Max Out Freq
3-00 Reference Range [Min-Max] 0% = 4 mA;
100% = 20 mA
3-00 Reference Range [-Max-Max] -100% = 4 mA; 0% = 12 mA; +100% = 20 mA [132] Feedback
4-20mA [133] Motor cur.
4-20mA
Value is taken from 16-37 Inv. Max. Current.
Inverter max. current (160% current) is equal to 20 mA.
Example: Inverter norm current (11 kW) = 24 A. 160% = 38.4 A. Motor norm current = 22 A Read-out 11.46 mA.
16 mA x 22 A
38.4 A + 4 mA = 13.17 mA
In case the norm motor current is equal to 20 mA, the output setting of 6-62 Terminal X30/8 Max. Scale is:
IVLTMax x 100
IMotorNorm = 38.4 x 10022 = 175 %
Parameter Descriptions Operating Instructions VLT® CDS302 and CDS303
6 6
6-50 Terminal 42 Output
Option: Function:
[134] Torq.% lim 4-20 mA
The torque setting is related to setting in 4-16 Torque Limit Motor Mode.
[135] Torq.%
nom 4-20 mA
The torque setting is related to the motor torque setting.
[136] Power 4-20mA
Taken from 1-20 Motor Power [kW]
[137] Speed 4-20mA
Taken from 3-03 Maximum Reference. 20 mA
= Value in 3-03 Maximum Reference.
[138] Torque 4-20mA
Torque reference related to 160% torque.
[139] Bus ctrl.
0-20 mA
An output value set from fieldbus process data. The output will work independently of internal functions in the frequency converter.
[140] Bus ctrl.
4-20 mA
An output value set from fieldbus process data. The output will work independently of internal functions in the frequency converter.
[141] Bus ctrl 0-20mA t.o.
4-54 Warning Reference Low defines the behaviour of the analog output in case of bus time-out.
[142] Bus ctrl 4-20mA t.o.
4-54 Warning Reference Low defines the behaviour of the analog output in case of bus time-out.
[150] Max Out Fr 4-20mA
0 Hz = 0 mA,4-19 Max Output Frequency = 20 mA.
6-51 Terminal 42 Output Min Scale
Range: Function:
0.00 %* [0.00 -200.00 %]
Scale for the minimum output (0 or 4 mA) of the analog signal at terminal 42.
Set the value to be the percentage of the full range of the variable selected in 6-50 Terminal 42 Output.
6-52 Terminal 42 Output Max Scale
Range: Function:
100.00
%*
[0.00 -200.00 %]
Scale the maximum output of the selected analog signal at terminal 42. Set the value to the maximum value of the current signal output. Scale the output to give a current lower than 20 mA at full scale; or 20 mA at an output below 100% of the maximum signal value. If 20 mA is the desired output current at a value between 0 - 100% of the full-scale output, programme the
percentage value in the parameter, i.e. 50%
= 20 mA. If a current between 4 and 20 mA is desired at maximum output (100%), calculate the percentage value as follows:
20 mA / desired maximum current x 100 %
6-53 Terminal 42 Output Bus Control
Range: Function:
0.00 %* [0.00 - 100.00 %] Holds the level of Output 42 if controlled by bus.
6
6
6.8 Parameters: 7-** Controllers
7-06 Speed PID Lowpass Filter Time
Range: Function:
Size related*
[1.0 -100.0 ms]
Set a time constant for the speed control low-pass filter. The low-pass filter improves steady-state performance and dampens oscillations on the feedback signal. This is an advantage if there is a great amount on noise in the system, see Illustration 6.9. For example, if a time constant (τ) of 100 ms is programmed, the cut-off frequency for the low-pass filter will be 1/0.1= 10 RAD/s., corresponding to (10/2 x π) = 1.6 Hz. The PID regulator only regulates a feedback signal that varies by a frequency of less than 1.6 Hz. If the feedback signal varies by a higher frequency than 1.6 Hz, the PID regulator does not react.
Practical settings of 7-06 Speed PID Lowpass Filter Time taken from the number of pulses per revolutions from encoder:
Encoder PPR 7-06 Speed PID Lowpass Filter Time
512 10 ms
1024 5 ms
2048 2 ms
4096 1 ms
Table 6.9
NOTE
Severe filtering can be detrimental to dynamic performance.
This parameter is used with 1-00 Configuration Mode [1]
Speed closed loop and [2] Torque control.
The filter time in flux sensorless must be adjusted to 3-5 ms.
0.6
0.6 fg = 10 Hz
175ZA293.11
Feedback
Disturbed feedback signal
t (Sec.)
t (Sec.) Filtered feedback signal
Lowpass filter
Feedback
Illustration 6.9