I586 GB 01 19
12
Manual mode (MAN)
In MAN mode the PID control is de-activated and the variable speed drive works with manual regulation of the frequency setpoint via a potentiometer connected to the AI2 analog input (type 0-10V).
In this example we configure the variable speed drive to provide an output frequency of 0Hz when the potentiometer is at minimum of its regulation scale (0V) and a frequency of 50Hz when the potentiometer is at
maximum (10V).
Example of use.
Once the parameters listed above have been set on the VLA1, test the functioning:
– Keep opened the DI2 digital input to allow the enable of the automatic mode (AUT).
– With the
buttons of the keypad set a PID setpoint, which for this specific example it corresponds to a pressure setpoint. For example, set a PID setpoint of 4.0 PID Unit (= 4 Bar).
– The VLA1 read the value of the pressure of the plant (PID feedback) from the AI1 analog input, to which is connected the output of a pressure sensor. The 0- 10V voltage signal of the pressure sensor is
automatically transformed by the VLA1 in a pressure value according to the parameters previously set (in this example: 0V = 0 Bar, 10V = 15 Bar).
– Close the DI1 digital input to run the motor.
– If the pressure of the plant is lower than the setpoint (e.g. 2 Bar, which is lower than 4 Bar) the VLA1 increases the speed of the motor by regulating the output frequency until the PID setpoint is reached. In this
specific example, the output frequency of the drive when PID control is active is limited to the 20% and 80% of the maximum frequency (50Hz), which means from 10Hz to 40Hz.
– If you want to switch the operating mode to manual mode (MAN) close the DI2 digital input.
– Now the PID control is de-activated (the value of AI1 signal is ignored). The output frequency of the drive is adjusted with the external potentiometer, connected to the AI2 analog input. In this specific example, the
output frequency regulated with the potentiometer can be adjusted from 0Hz to 50Hz.
– To command the motor stop, open the DI1 digital input.
Parameter Function Setting Description
P201.01 Frequency setpoint source 3 Frequency adjusted with analog input 2 (AI2)
P201.02 PID setpoint source 1 PID setpoint adjusted from keypad
P210.00 Minimum frequency 0 Hz Insert the value of the minimum frequency
P211.00 Maximum frequency 50 Hz Insert the value of the maximum frequency
P220.00 Acceleration time 5 sec Insert the value of the acceleration time
P221.00 Deceleration time 5 sec Insert the value of the deceleration time
I/O configuration (AI1 = PID feedback, AI2 = frequency setpoint, DI1 = run/stop, DI2 = AUT-MAN mode switch)
P430.01 Analog input 1 (AI1) configuration 0 Analog signal type 0-10V
P430.04 PID value when AI1 is at minimum 0 Minimum value of AI1 signal expressed in PID Unit (0V = 0 PID unit, in this
example correspondent to 0 Bar of pressure)
P430.05 PID value when AI1 is at maximum 15 Maximum value of AI1 signal expressed in PID Unit (10V = 15 PID unit, in this
example correspondent to 15 Bar of pressure)
P431.01 Analog input 2 (AI2) configuration 0 Analog signal type 0-10V
P431.02 Frequency value when AI2 is at minimum 0 Hz Insert the frequency value correspondent to AI2 signal at minimum (0V)
P431.03 Frequency value when AI2 is at maximum 50 Hz Insert the frequency value correspondent to AI2 signal at maximum (10V)
P400.02 Run/stop command 11 Run/stop command from digital input DI1
P400.45 Deactivate PID control 12 DI2 opened = PID enabled, provided that P600.01=1 (AUT mode)
DI2 closed = PID disabled (MAN mode)
Configuration of PID parameters (AUT mode)
P600.01 PID enable 1 PID function enabled
P600.02 PID feedback source 1 PID feedback connected to analog input AI1
P600.05 Minimum PID operating frequency 20% Minimum value of the operating frequency of the PID control expressed as %
of the maximum frequency of the drive P211.00 (100% = P211.00 = 50Hz)
In this example: 20% of 50Hz = 10Hz
P600.06 Maximum PID operating frequency 80% Maximum value of the operating frequency of the PID control expressed as %
of the maximum frequency of the drive P211.00 (100% = P211.00 = 50Hz)
In this example: 80% of 50Hz = 40Hz
P605.01 Minimum value of the PID setpoint 2 Minimum value of the settable PID setpoint, expressed in PID unit.
In this example: 2 PID Unit, correspondent to 2 Bar of pressure.
P605.02 Maximum value of the PID setpoint 8 Maximum value of the settable PID setpoint, expressed in PID unit.
In this example: 8 PID Unit, correspondent to 8 Bar of pressure.
P606.01 PID acceleration time 10 sec Insert the acceleration time of the PID control
P606.02 PID deceleration time 10 sec Insert the deceleration time of the PID control
