Frequently Asked Questions (Automation)
Questions From You!
The problem is that the output terminal (motor) is not connected to the inverter. This is a normal result as software is programmed this way for security measures. The problem can be fixed by connecting the motor to the inverter. But the same situation can be encountered when the motor is connected. The safety program is activated according to the amount of output current produced from the inverter. The output voltage may drop if the motor capacity is small compared to the inverter causing very small output current. If this program makes it difficult to use and there are requests by end users, please contact us.
3-wire operation seals the signal input (the signal remains closed even after the button is pressed) and is also used to start the inverter with a push of a button. To enable 3-wire operation it is necessary to follow the circuit sequence. The minimum input time (t) for 3-wire operation is 1 ms and operation stops if forward and reverse operation commands are entered simultaneously.
1-Make sure the Run command is entered.
2- Activate the Power On Run function in the ADV group.
3-Please check the output contact signal.
When the motor starts idling the inverter, the quick start function estimates and calculates the idle speed and helps the motor to run safely. This function can be used as a start function by selecting Quick Start-1 or Quick Start-2 depending on the application used. Quick Start-1 is a function that allows stable operation in the low speed range (10 Hz or less) if the direction of the start command is the same when the engine is idling and restarting. Normal speed may not be found if the direction of the run command is reversed when the engine is idling and restarting. The Quick Start-2 function is a function that performs stable speed seeking work regardless of engine idling direction or driving instructions. If the engine idle speed is low (below 10-15 Hz), the speed may not be correct as a possible disadvantage.
In EtherCAD connection, synchronized data connection is provided via Process Data Object (PDO). Process data includes TxPDO sent from the inverter to the EtherCAD Master and RxPDO sent from the EtherCAD Master to the inverter. There are two types of profiles such as CiA402 and LS device profile. With the LS device profile(PDO3), the user can randomly match the data defined in the object dictionary of the inverter via COM31-COM38 and COM51-COM58. For the CiA402 profile, the control word is fixed with target speed, status word and speed actual value.
Sensorless vector control is the process of performing vector control without rotational speed feedback from the motor but with the estimated rotational speed of the motor calculated by the inverter. Compared to V/F control, sensorless vector control can produce larger torque at a lower current level. For high performance operation , the characteristic of the motor connected to the inverter output should be measured. Before running the sensorless vector operation, you can use autotuning(AUTOUN) to measure the parameters. To run high performance sensorless vector control, inverter and motor capacities must be the same. If the motor capacity is more than two levels smaller than the inverter capacity, the control may be faulty. If you encounter this situation, change the control mode to V/F control. When working with sensorless vector control, do not connect more than one motor to the inverter output.
Use frequency hopping to avoid mechanical resonance frequencies. The inverter will avoid certain frequency ranges during acceleration and deceleration. The operating frequencies cannot be adjusted within the preset frequency hopping band. When the operating frequency is increased while the frequency parameter setting value (voltage, current, RS-485 communication, keypad setting, etc.) is within the frequency jump band, the frequency is maintained at the lower limit value of the frequency band. Then, the frequency will rise when the frequency parameter setting exceeds the frequency range used by the frequency skip band.
The distance between Inverter-Motor /50m/100m/more than 100m is allowed. Carrier frequency / less than 15 kH (15.0) / less than 10 kH (10.0) / less than 5 kH (5.0). The inverter has electron-thermal protection function to protect the motor from overheating. You do not need to install an external thermal relay. But when you start a large number of mortor or multipole motors, install the thermal relay (OCR) between the motor and the inverter.
The lowest frequency and the motion frequency are not the same. The lowest frequency motor temperature is about 3Hz considering the rising and moving torque. But the moving frequency is actually about 0.2~5Hz as a point to get output voltage.
PWM (Pulse Width Modulation) changes the voltage by changing the voltage output time on the pulse without changing the smoothed DC voltage. The sine wave that sequentially converts the output pulse width so that the motors with current flowing become a sine wave is called PWM. It becomes the main form because of the small torque wave of the low frequency region. PAM (Pulse Amplitude Modulation) modifies the DC current amplitude, so it has features with small harmonic components and driving noise.
iS7 has two quickstart modes. “Quick Start-1” captures speed at higher response time and is less sensitive to PI gain values. “Quick Start-2” can recognize the direction and has higher accuracy in the low speed range. Use “Quick Start-2” to prevent reverse running.
Please find the following two methods when applying the copy and history feature using the iS7 digital installer. 1) System without fieldbus communication When the control panel is a system without any fieldbus communication, it is correct to use CNF-46 to read parameters from CPU and CNF-47 to write to a new drive. Reading is copying from the CPU to the keypad and writing is pasting the settings from the current inverter to a new one. 2) System using fieldbus communication (options such as CC-link, CANopen, Profibus-DP) When an option card is connected to the inverter, all the settings made via the keypad are entered and the option card is saved in the CPU. It is therefore recommended to always go over a Comm. It is the update process using COM-94 to apply the fieldbus settings to the main control card of the inverter. Additionally, when copying and pasting the settings on the keypad, follow these steps: 1) CNF-48=Saving Parameters: This operation saves the dialog group settings to the main control board. 2) CNF-46= Parameter Reading and CNF-47=Parameter Writing: It is exactly the same process as non-fieldbus option type. 3) COM-94= Comm. Update: Applies the copied communication settings to the new inverter.
In case [Analog output item selection] is “0”, that is, [Output frequency], “10V” analog output voltage is the maximum frequency (F21). When [Analog output item selection] is set to “1” which means [Output current], it will be 150% of 10V Inverter rated current. When [Analog output item selection] is set to “2” which means [Output voltage], the output voltage of 10V 200V type Inverter will be 282Vac and 10V of the output voltage of 400V type Inverter will be 564Vac. When [Analog output item selection] is set to “3”, it means [Inverter DC Link Voltage], 10V will be 400Vdc DC Link voltage in 200V type Inverter and 10V will be 800Vdc DC Link voltage in 400V type Inverter.
For vertical loads, the multi-function relay settings are mostly used to control brake signals. When using the FDT-4 function, the relay signal turns on according to the set frequency. When the brake signal is controlled by the BR control function, the relay is switched on and off according to the frequency and current conditions. Allows more stable motor control due to reduced starting current when using the BR control function.
Automatic tuning of the VFD is the process by which the drive measures the impedance of a motor to adjust the motor control algorithm. The measured values are used to determine the voltage and current at different speeds. As a result, this allows the motor load to be driven more effectively and better speed regulation, especially when running without feedback (open loop). The measured values consist of Rs, Lsigma, Ls and Tr. Rs is a stator resistance, Lsigma is a leakage inductance, Ls is a stator inductance, and Tr is a time constant for the rotor.
DriveView7 supports additional functions such as “Trend”. The trend function is the monitor that allows the user to observe the variables as a graph. In the trend function, you can watch four different channels at the same time. Through this function, the user can monitor "Output frequency", "Output Current", "Output voltage", "D/I state", "D/O state" and so on.
Obviously, “Torque limit” and “Stall prevention” are similar because both functions limit the output current. But they have different working conditions. “Torque limit” operates based on peak current and “Stagnation prevention” operates on RMS (Root Mean Square) value of current. The current value displayed on the keypad is the RMS value. Therefore, the output current appears to be limited below the torque limit. The peak value can be obtained by multiplying the RMS current by the root of two.
In case of S100 single phase, please connect terminals “R” and “T”. There are three power input terminals. But there is no screw in the "S" terminal as you don't need to connect it.
AC/DC Diode rectifier may cause current distortion on the input side of the inverter. This results in a low power factor which reduces the efficiency of the system. It can reduce these harmonic distortions, which have bad effects on the reactor electrical transformer and electronic devices. Also, AC and DC Reactor should not be accidentally installed in an Inverter because voltage drop may occur.
As an example, you need to use Expansion I/O using terminal V2 for analog input. In this case, you need to connect the 5G-CM terminal and the VR+-V2-5G terminals. Because Expansion I/O needs external power supply.
In the case of PID control, the Skip Frequency function cannot be used as the load state can change at any time.
We offer internal DB units from 11 to 22 kW. You can use terminals B1 and B2 to connect the DB resistor. The short pin must not be removed when the connection is established. Also, you should not connect the unit while it is energized.
“The voltage characteristics of the DB resistor are as follows. Voltage level that turns DB resistor ON: 798Vdc, Voltage level that turns DB resistor OFF: 781Vdc, Voltage level that causes overvoltage fault: 8220Vdc.”
The maximum inverter operating frequency is 300Hz under vector control condition. In the case of V/F control mode, the output frequency goes up to 400Hz.
While the motor speed is reduced by the inverter, the motor acts as an induction generator and sends voltage to the inverter in the opposite direction. In this way, the DC bus does not swell and the device does not switch to an overvoltage-related fault.
The power produced by the engine can be called Torque. In direct line motion, power is generally expressed in N units. In motors, power is expressed in Nm.
When the inverter reads the electrical characteristic of the induction motor and the drive motor, the inverter sets the parameter itself. Then it executes the sensorless vector control properly.
The driver drives the motor by making estimations from the current drawn according to the characteristics of the motor and the magnetic field effects it creates, without receiving any feedback from the system driven by the motor.
V.V.V.F (Variable Voltage – Variable Frequency) is a variable frequency inverter path that changes frequency and voltage simultaneously. It is used synonymously with INVERTER.