Ex: Communication setting for an AC motor drive (default: station 1, ASCII mode) and commands are given as following via MODBUS:

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1 How do you control Delta s AC motor drive with a computer? Delta s AC motor drive is designed with communication ports for RS485 connection and it supports the MODBUS protocol for data transmission and exchanges. Users can read/write data from Delta s AC motor drive using a computer simply by installing any kind of MODBUS software to the PC. For a program writer, Delta provides MODBUS DLL file to facilitate the programming process. Please download the Delta Modbus DLL Library from Delta website: The DLL file allows users to modify the parameters and also to monitor and control the AC motor drive. Ex: Communication setting for an AC motor drive (default: station 1, ASCII mode) and commands are given as following via MODBUS: AC motor drive begins operation : D7\x0D\x0A AC motor drive stops operation : D7\x0D\x0A The code represents: 01= station number 06= function code (write in) 2000H = AC motor drive s register For more detail, please refer to any AC motor drive series user manual. What are the differences between the C200 series and C2000 series AC motor drives? The AC motor drive C200 series is designed for light-duty load applications up to 10HP and replaces the VFD-B series. It fits the requirements of the low-power inverter market. The C2000 series is designed for normal-duty to heavy-duty load applications. What are the features of the C200 series? 1. High reliability, high stability, long-life, easy tuning 2. Compact drive size that facilitates installation 3. Advanced PID control 4. Built-in PLC programming functions, 5K steps capacity. 5. Built-in high speed communication protocols CANopen and MODBUS RS Hang type LED digital keypad 7. Ability to drive both IM/PM motors 8. High-level field oriented control modes: FOC+PG, FOC Sensorless 9. Provides various optional communication modules for building a network. 10. Enhanced control board coating and enclosure IP20, UL Open type, NEMA1. Please describe the manual/auto switching function of the C2000 series AC motor drive for HVAC applications. The HVAC industry requires flexible functions such as manual/auto control modes or local/remote control modes for different application conditions. These control modes can be used as a treatment to far-end remote control disconnection or for technical engineers to adjust HVAC controls manually. The C2000 series AC motor drive provides designated parameters and special wiring for the user to switch between manual/auto controls easily. 1. Parameter setting Pr.00-20=2 Source of frequency command is analog signal Pr.03-00=1 frequency command setting is AVI Pr =1 frequency command setting is ACI Pr =16(MI1) Force setting source of frequency command to ACI 2. Setting description When MI1 is OFF, the source of frequency is AVI (0-10Vdc). When MI1 is ON, the source of frequency is ACI (4-20mA). FAQ FOR VFD

2 Can we use a platinum RTD to detect the motor temperature of C2000 series AC drives? Yes. First, connect the platinum RTD to the C2000 drive as shown in the following diagram. Then set the C2000 drive to output a steady current of 9mA at the AFM2 terminal and detect the voltage on the AVI terminal. Since the resistance of PT100 would change according to the temperature, the user can then find the current temperature by detecting the AVI voltage. To set up the C2000 AC motor drive: 1.Set Pr = 23 and Pr = 45 to output a steady 9mA current at the AFM2 terminal. 2.Set Pr = 11, use AVI to detect the voltage on PT Check the PT100 temperature chart to find the corresponding resistance value and calculate the voltage according to the value:.resistance * Steady Current = Voltage.When temperature =135 C, the resistance will be ohms. The voltage can then be calculated by *9mA = 1.37V..When temperature =150 C, the resistance will be ohms. The voltage can then be calculated by *9mA= 1.42V. 4.If the user wants to lower the frequency to 10Hz as the temperature reaches 135 C, set Pr = 1.37 an d Pr = 10 5.If the user wants the drive to output a warning and stop operation at 150 C, set Pr.06-57=1.42 and Pr.06-29= 1.

3 How do I select the fuses for a parallel DC bus connection of AC motor drives? a.dc power supplied to parallel DC bus connection b.independent AC power supplied to parallel DC bus connection What should I do when the LED of a VFD-M series drive displays a 8888 or 9999 error message? The fault may occur for the following reasons:.if the drive is still operating normally but the LED displays an error message, the LED is malfunctioning. Please replace the LED control board..if the drive has stopped operating, please reapply the power again. If the drive is still not operating, then it is the drive that is malfunctioning. Please send your VFD-M series for repair or replace it with a new drive. Unable to establish a communication connection with the AC motor drive. Please verify the type of communication interface you are using then check the cable connection and parameter settings. What types of communication interfaces do Delta s AC motor drives support? Delta's AC motor drives support international standard MODBUS protocols and connections can be established with the RS-485 communication interface. What other communication interfaces do Delta AC motor drives support besides the standard MODBUS protocols? Delta's new generation AC motor drives C2000 series, CP2000 series and C200 series also support PROFIBUS- DP, Device Net, MODBUS TCP and EtherNet/IP cards and these high speed communication interfaces are all available as optional accessories. The C2000 series and VFD-VL series also offer a built-in CANopen protocol and the CP2000 series offers a built-in BACnet communication interface.

4 How do I set up the AC motor drive s communication parameters? The communication parameters can be set in parameter group 09 of AC motor drives. How could the AC motor drive output voltage measured by a user be as high as 600V? The voltage the user has measured is the DC voltage at PWM output. The user actually needs to measure the AC motor drive output voltage using an electric meter with RMS function or an analog meter. What are the advantages of installing a transducer at the drive s input side?.to lower the AC motor drive s harmonics..to lower the surrounding voltage and current impact on the AC motor drive, such as the surge voltage, the current of surrounding devices, and the surge voltage of the mains..to improve the power factor. Why would the output current of an AC motor drive measured with a handheld multi-meter show a different value than the inverter? The handheld multi-meter can precisely measure the AC motor drive s current in the range of 40 ~ 60Hz. If the current does not fall within this range (40 ~ 60Hz) the measured value may deviate. How is a handheld multi-meter used to measure IGBT? Switch the electric meter to diode position. Use black stick to touch DC+ (+1 +2) and use the red stick to touch R, S, T, U, V, W. The measured value is forward bias 0.4. Use the red stick to touch DC- (-) and the black stick to touch R, S, T, U, V, W. The measured value is forward bias 0.4.

5 For the C2000 series AC motor drive, how do you use the built-in PLC function to record the frequency at power failure? The frequency at power failure can be recorded by setting M1005 (fault indication for the C2000) and special D1020 (output frequency) with delay time, such as shown in the figure:

6 How can the C2000 series AC motor drive execute the process control function, if it is not one of the built-in functions supported? The built-in PLC function of the C2000 can execute the process control. The C2000 s built-in PLC function can write up to 10K steps. D0: 1st step operation frequency D1: 1st step speed acceleration time D2: 1st step speed deceleration time D3: 1st step continuous duration D4: 2nd step operation frequency D5: 2nd step speed acceleration time D6: 2nd step speed deceleration time D7: 2nd step continuous duration After trigger M0, the process curve runs as: What is the theory behind the motor speed display function in the C2000 series AC motor drive? Usually, there are two modes. For the open-loop mode, the speed is calculated by the equation: n=120f/p to estimate motor speed. For the close-loop mode, an encoder is mounted to the motor. The encoder feedback (signal) is sent to the PG card for displaying the actual motor speed. In this case, the motor speed is precisely controlled.

7 How to set the acceleration and deceleration time of the AC Motor Drive? The acceleration time is to determine the time required for AC motor drive ramp from 0.0Hz to its maximum output frequency. The deceleration time is to determine the time required for AC motor drive to decelerate from its maximum output frequency to 0.0Hz. When an AC motor drive operates in a full load condition, large load inertia is likely to occur and cause motor continues to ramp when the output is stopped. Delta s AC motor drive offers optimize acceleration and deceleration function that regulate the accelerating and decelerating speed. It moderates the vibration when activating and stopping the loading. As the motor detects a minimum level of torque, it will accelerate to the setting level of frequency in the shortest period of time with a smooth start-up current. For deceleration, Delta s AC motor drive will estimate the amount of regenerative energy that will be produced and smoothly stop the motor in the meanwhile. What is the input resistance of positive temperature coefficient (PTC) thermistor for VFD-E series and VFD- VE series AC motor drive? Before answering the question, it is important to know the protection level for PTC is 1330Ω; and for AC motor drive that supports 10.5V of DC voltage, the protection level is 2.4V. In the following figure, impedance for AVI in VFD-E series AC motor drive is 47KΩ and in VFD-VE series AC motor drive is 2MΩ; impedance for ACI in VFD-E series AC motor drive is 100Ω and in VFD-VE series AC motor drive is 250KΩ. With the above information, we can calculate for X. For VFD-E series, the input resistance of PTC is 4.4KΩ.

8 Technically, VFD-VE series AC motor drive would have greater internal resistance when connected in parallel which means smaller impedance effect. In the following example, since impedance for AVI in VFD-VE series (2MΩ) is greater than VFD-E series (47KΩ), VFD-VE series can be connected in parallel and the recommended range for the resistor is 1Ω to 10KΩ. Can a three-phase AC motor drive connect to a single-phase power? The greatest difference among Delta single-phase and three-phase AC motor drive is the power capacity. Singlephase model is designed for greater power capacity. If a three-phase model is connected to a single-phase power, it may not provide enough output current and may cause a phase loss problem. To ensure a normal system operation, please connect three-phase AC motor drive to the accurate power source. When Pulse Generator PG Card is applied to AC Motor Drive, how do I set up the parameter and hardware? The hardware needs to first install a PG Card. On the PG Card, choose one of the encoder setting: Open-Collector or Line-Driver, and make sure the voltage setting is accurate. Next, set up the pulse per encoder rotation and pulse type on parameter setting. For example, Delta VFD-VE AC drive uses EMV-PG01X series PG Card with 1,024 pulses per encoder rotation and encoder setting is Open-Collector 12V. The PG card settings : For parameter setting of 10-00, pulse per encoder rotation is 1,024. Before parameter setting, it is important to select a pulse type (AB phase, pulse and direction or single pulse).

9 the motor rotation speed on the HMI. Last, set parameter to 7 then you will see Which modes can be used to adjust the motor speed? The motor speed can be adjusted by the following ways: 1. Variable resistor on the keypad 2. External analog voltage/current signal 3. Multi-function input terminals to control multi-speed control 4. Communication method by using the host controller What is stall prevention? When the acceleration time is too short and the change of output frequency is faster than the motor speed, the AC motor drive will stop due to over-current. This situation is called stall. To have normal motor operation, it needs to control frequency by the output current. Therefore, the acceleration rate should be decreased when the output current is too large. It is also the same as in the deceleration. Can VFD-B be used for hi-speed operation, e.g. for spindles? Yes, with firmware 4.08 it is possible to operate VFD-B up to 2000Hz. Can VFD-B the Modbus addresses 2203H, 2204H and 2205H be read, even if the analogue inputs AVI, ACI, and AUI respectively, are not used? Yes, this is possible. They can always be read. Can VFD-B the EF input be used as a PTC input? A The EF input of VFD-B (and also all other drives) cannot be used to connect a PTC. It is a digital input with only an on and off state. What are the advantages when using without encoder? I.Simple wiring. II.Don t need to care about the influence that RF noise makes to the low-voltage signal of encoder III.Don t need to care about the high malfunction ratio of encoder in the vibration applications What is vector control? In the AC motor, rotor generates flux by the current from stator winding induction. There are two elements in stator current, one affects flux and the other affects the output torque of motor. The flux vector can control these two elements individually so that the speed and torque can be controlled.

10 What is Auto Tuning? Auto Tuning is to measure the motor parameters automatically, including no-load current, stator resistance, rotor resistance, stator inductive reactance, rotor inductive reactance, etc. These parameters are used to calculate the torque estimation and slip compensation. With auto tuning, it can get accurate speed without encoder. What are the inverter components? They are SCR, GTO, BJT and IGBT. By 1970, SCR is the only one component. After that, they are GTO->BJT- >IGBT. What's difference between the same accel./decel. time setting and the different accel./decel. time setting for the application? It needs to set the different accel. time and decel. time for the strict time requirement applications. But in the fan and drive applications, the accel./decel. time can be set the same due to longer accel./decel. time requirement. How should I do to enhance the brake performance? Normally, the brake of the AC motor drive is 10%~20% of rated torque. But it can be increased when using with brake unit. How should I do when the actual speed is different from the desired speed? When the AC motor drive is controlled by the open loop, the motor speed will be varied within ±5% X rated slip. You can use the AC motor drive with the PG feedback function when the accurate speed is required. If the speed precision will be increased when using PG feedback control? Normally, it will. But the improvement will depend on the resolution of encoder and output frequency. What is stall prevention? When the accel./decel. time is too short and the change of output frequency is faster than the motor speed, the AC motor drive will stop due to over-current. This situation is called stall. To have normal motor operation, it needs to control frequency by the output current. Therefore, the accel. rate should be decreased when the output current is too large. That is stall prevention What is closed-loop/open-loop control? For closed-loop control, the motor is used with encoder and sends the actual speed to the AC motor drive via PG card. For the open-loop control, it is used without encoder. If users can use the constant torque when the frequency exceeds 60Hz? For general applications, the constant torque can t be used for the frequency above 60Hz. Because the voltage and power are usually constant when the frequency is above 60Hz. When you need to have constant torque in high speed, please pay attention for choosing motors and drives. How will the motor s torque be when V and f are changed in proportion? The voltage will be reduced with frequency in proportion. The torque is also decreased in low speed because the reduced AC resistance and the constant DC resistance. Therefore, it can get higher start torque by increasing output voltage in the low frequency. Many methods can be used to get it, such as auto torque compensation, high start torque V/f curve and potentiometer adjustment. In general, the frequency can be set to 6-60Hz (1:10). If the power still outputs when the frequency is below 6Hz?

11 It still outputs power when the frequency is below 6Hz. According to the setting of motor temperature rise and start torque, it can output rated torque without overheat problem when the frequency is 6Hz. What is V/f mode? The voltage will be reduced with frequency as described in question 4. The ratio of V to f is decided in advance by motor characteristics. If it is driven by the commercial power, the current will be increased when the voltage is decreased. If it is driven by the AC motor drive, will the current be increased when the frequency and voltage are decreased? When the frequency is decreased, the current will be increased with the same output power. However, the current will be almost the same for the constant torque. How will the start current and start torque be when a motor is driven by the AC motor drive? Normally, it will generate 6 to 7 times start current when the commercial power is applied directly and causes electric inrush. The motor can be started smoothly when driving by the AC motor drive and the frequency and voltage will be increased with acceleration. The start current should be below 150% (125%~200% for the different models), and the start torque is from 70% to 120% rated torque. For the drive with auto-enhanced torque and the start torque is over 100%, it can be started with full load. What is the difference between PWM and PAM? PWM is the abbreviation of Pulse Width Modulation. It is a way to adjust output and waveform by changing the pulse width regularly. PAM is the abbreviation of Pulse Amplitude Modulation. It is a way to adjust output and waveform by changing the pulse amplitude regularly. Why must the voltage and current of drives change in proportion? The torque of asynchronous motor is generated by interaction between magnetic flux of motor and current in rotor. In rated frequency of motors, using constant voltage with reduced frequency, it will result in over-magnetic flux, magnetic saturation, and even cause motor damage. Therefore, frequency and voltage have to be changed in proportion. In other words, the output voltage should be changed with frequency. To fix the magnetic flux of motor, it can avoid weaken flux and magnetic saturation. This control method is usually used in energy-saving drives for fan and pump. What is AC motor drive? It is an equipment used to control the speed and torque of an induct motor. The DC voltage can become a variable voltage and variable frequency of alternating current by the inverter after using the converter to rectify 1-phase or 3- phase AC power to direct current. For general-purpose AC motor drives, the voltage will be changed with frequency changes. Therefore, the AC motor drive is called VVVF(Variable Voltage Variable Frequency) for short.