What's the biggest difference between the old PR mode of the ASDA-AB and the new PR mode of the ASDA-A2?

Please refer to the comparison table below.

The Ways to Call a PR There are 64 position settings in PR mode. PR 0 is homing mode and the others (PR 1 ~ 63) can be user-defined. For the ways to call a PR, please refer to the table below:

Why does the 2-axis interpolation function of the ASDA- M series servo drive provide better performance than two ASDA-A2 series servo drives?

If a synchronous error occurs between two ASDA-A2 series servo drives, the user must correct the error through a host (external) controller. However, if a synchronous error occurs while using the ASDA-M series, the data of the two axes is exchanged in the same CPU without any time delay and the error is corrected immediately, providing excellent real time synchronous control. The host (external) controller is almost eliminated.

How does a user ensure that the positioning is compl ete when using the PR mode built-in to the ASDA-A2 series servo drive?

A user can monitor variables or scope function via software to check the status of the digital output (DO), MC_OK (DO code is 0x17). Please note that DO: MC_OK is available in PR mode only. It cannot be activated in other control modes. When DO: CMD_OK is triggered, it indicates that the PR command is complete (use CMD_OK to detect if the internal position command is complete). At this time, DO: TPOS activates to indicate that the target position is reached. Then, DO: MC_OK becomes ON to show the position command has output and the positioning is complete. Sometimes DO: TPOS is activated even when the PR command is not delivered. At this time, the positioning is not yet complete. This will cause the system to take the wrong action. If DO: MC_OK is used, it ensures the position command actually executes and the target position is reached. Timing chart:

What's the biggest difference between the ASDA-M and ASDA- A2?

The ASDA-M series includes 3 axes servo drives in one frame to provide 3 axes synchronous motion control and it supports real-time data exchange among 3 axes without any time delay. It is also equipped with a contour analysis function to enhance the diagnosis capability of the system.

Delta’s ASDA-A2 Series servo system provides a phase a lignment function. What is a phase alignment function? What are its main applications? What are the a dvantages of using Delta’s ASDA-A2 Series with this function rather than a traditional machine system?

The phase alignment function is a phase correction function used to adjust the pulse phase. When the specified digital input is triggered, the alignment function is enabled to perform the correction automatically. Main applications include packaging machines, sealing machines, roll feeders and high-speed labeling machines. This function can reduce the accumulated errors that occur during processing operations. It can also ensure the accuracy of positioning within ±1mm when switching between high speed and low speed. 1.Traditional Machine System: The feeder axis is the master axis in constant speed motion and the cutter axis is the slave axis in variable speed motion (maybe it adopts a traditional machine cam or the electronic cam built into the ASDA-A2 Series servo system). The disadvantages are that the processing speed is slow, the productivity is hard to increase, and the frequency of motor acceleration and deceleration is high. These will decrease the motor life and make the system more unstable and hard to control. 2.ASDA-A2 System with Phase Alignment Function: The cutter axis is the master axis and the feeder axis is the slave axis. Both master and slave axis are in constant speed motion. The advantages are that the processing speed is quick and the productivity is easy to increase. The aid of the phase alignment function smooths the motor operation and ensures the accuracy of positioning when switching between high speed and low speed.

What is the Compare Function?

The Compare function is the reverse process of the Capture function. The items stored in the data array will be compared to the signal of a physical axis (main encoder, linear encoder, or pulse train). The Compare function uses the instant position of the motion axis to compare with the value which is stored in the data array. When the compare conditions are satisfied, the DO4 signal will output immediately for motion control. The signal to DO4 for the Compare function is a physical signal and cannot be simulated from software. It can complete a precise Compare function for high-speed motion axis. The characteristics of the Compare function are described as follows:

When selecting the appropriate Delta servo drive, ho w do you set up the proper gear ratio of the gear spe ed reducer to determine the servo drive size?

In a mechanical system, you can use the gear speed reducer to change the output and motor speed and reduce the load inertia. Please refer to the following figure and the equation shown below.

For example, if the load inertia is equal to 1000Kg x m2 and a gear speed reducer with a speed ratio of 5:1 is used, the load inertia can be decreased to 40 Kg x m2. If the load inertia is equal to 1000Kg x m2 and a gear speed reducer with a speed ratio of 10:1 is used, the load inertia can be decreased to 10 Kg x m2. Under the same mechanical conditions, if the operating speed of the machine is fixed, the required motor output torque will decrease in accordance with the decreasing load inertia. When this situation occurs, please check if the motor speed has reached its upper limit (3000 rpm or 5000 rpm). If the motor speed has not reached its upper limit, using a suitable gear speed reducer can decrease the load inertia and enhance the motor speed. In addition, when a gear speed reducer is used, you can choose a motor with a smaller rated output power to help achieve optimum system performance.

How do you use the full-closed control function of the ASDA-A2 series AC servo drive in PT mode?

STEP1: Confirm and perform wiring Position Feedback Signal Connector CN5 (for Full-closed Control) The servo drive can be connected to a linear encoder or external encoder to constitute a full-closed loop via this position feedback signal connector CN5. In position mode, the pulse position commands given by the external controller just refer to the control loop structure of the external linear encoder. Please refer to Chapter 6 for more description.

CN5 Terminal Signal Identification

STEP2: Check if the servo drive is not in the full-closed control mode (check if the full-closed control function is disabled). Parameter P1-74: Enable/Disable full-closed control function. This parameter is used to determine the function of full-closed control.

Please note that before using the full-closed control function, the full-closed control function selection of P1-74 must be set to 0. STEP3: Activate ASDA-Soft configuration software and set P1-72 to 80000. Parameter P1-72: How many pulses will be sent from the linear encoder referring to one turn of the servo motor. STEP4: Enable Data Scope function, a PC-based digital oscilloscope function of the ASDA-Soft configuration software. Select two channels, Motor feedback pulse number (encoder unit, 1280000 pulse/rev) and external encoder feedback pulse number (The data length of these two channels are both 32-bit). STEP5: Use the Data Scope function to measure the feedback pulse number sent from the linear encoder referring to one turn of the servo motor. If a ball screw is used, the customer will provide the pitch of the ball screw and the resolution of the linear encoder. When the pitch of ball screw is 5mm and the resolution of the linear encoder is 0.5um/pulse, the feedback pulse number sent from the linear encoder for one turn of the servo motor should be

pulse/rev. Set the servo drive for servo on and use the JOG function to control the servo to move in one direction at low speed safely. At this time, you will see data as in the following Figure 1.

In the above figure, for one turn of travel, the traveling distance of the motor encoder is 2326786 pulses and the traveling distance of the linear encoder is -18178 pulses. The linear encoder feedback pulse numbers for one turn traveling is equal to:

If the customer does not know the pitch of the ball screw, please use the above equation to measure the linear encoder feedback pulse number for one turn of the servo motor. If the customer knows the pitch of the ball screw, please use the above equation to check if the linear encoder feedback pulse number for one turn of the servo motor is correct. STEP6: In Figure 1, you will find that the directions of both pulse trains are in reverse. One is positive and the other is negative trend. If not, set the polarity setting of the linear encoder of P1-74 to 1 for reversing the direction of motor encoder pulses from the linear encoder. You will then see both trends of the pulse trains are in the same direction (see Figure 2).

Please control the servo motor to run in the forward and reverse directions and ensure that the feedback pulse numbers in the forward and reverse directions are both correct.

When the pulse direction is a positive trend, the measured linear encoder feedback pulse number for one turn of the servo motor is about 10000 and the pulse trains increase in the same direction.

When the pulse direction is a negative trend, the measured linear encoder feedback pulse number for one turn of the servo motor is about 10000 and the pulse trains decrease in the same direction. STEP7: If the specification of your mechanism is already known, the customer can use P1-72 to count the linear encoder directly. If the specification of your mechanism is not known, the customer can use the PC data scope function to simulate the specification of your mechanism first and use P1-72 to count the linear encoder directly. STEP8: After P1-72 is set, use P1-74 to determine the polarity setting of the linear encoder and then enable the full-closed control function. Note: When the full-closed control function is enabled, the electronic gear ratio will refer to the command resolution of the linear encoder instead of the motor encoder. For example, when P1-44 and P1-45 are both set to 1 (the electronic gear ratio is set to 1:1), if P1-72 is set to 10000 pulses, then the linear encoder will move a one turn distance and feedback 10000 pulses. Please note that the setting of the electronic gear ratio is under full-close control function.

The ASDA-A series has a digital input with HOLD for motor stop function. When HOLD is activated the motor will stop. After HOLD is turned OFF, the motor will start again. Does the ASDA-A2 series provide the same function? Is there any digital input for the ASDA-A2 series that can perform the motor stop function in PR mode?

The ASDA-A2 series has a digital input, STOP, which is similar to the HOLD function of the ASDA-A series. The user can use the STOP digital input to perform the motor stop function in PR mode.

What is the data array function in the ASDA-A2 series AC servo drive? How can I use it?

The ASDA-A2 series provides many motion control functions, such as E-Cam, Capture, and Compare. The data array can keep data for E-Cam, Capture, and Compare with a maximum of up to 800 records. Access to Data Array: There is one index, P5-11 working along with two read/write windows, P5-12 and P5-13 for accessing the data array. For some external controllers resending data several times while communicating, it is better to put the index P5-11 before each read/write operation. In other words, set the desired read/write addresses by using P5-11 and then read/write the data through P5-12 or P5-13. For example, to write three consecutive numbers of data (100th, 200th, 300th), and save them into the address 11, 12, 13 of the data array, the operation steps are as follows: 1. When writing data through the keypad: Use P5-12, read/write window#1 because P5-13, read/write window#2 does not provide this function. 1) Set first address: Set P5-11=11 (the first address) 2) Write data: Set P5-12=100. (This is the first written data, 100th data and it is saved in address 11, i.e. P5-11. After the write operation is completed, the address of P5-11 will increase 1 automatically to address 12.) Set P5-12=200 (This is the second written data, 200th data and it is saved in address 12, i.e. P5-11. After the write operation is completed, the address of P5-11 will increase 1 automatically to address 13.) Set P5-12=300 (This is the third written data, 300th data and it is saved in address 13, i.e. P5-11. After the write operation is completed, the address of P5-11 will increase 1 automatically to address 14.) The user can then read the addresses 11, 12, and 13 and check the written values. 2. When reading data through the keypad: Use P5-13, read/write window#2 to read consecutive data. 1) Set the first address: Set P5-11=11 (the first address) 2) Read data: When the display shows P5-13: Press SET key the first time and the display shows the 100th data saved in address 11. Press MODE key to exit P5-13. Press SET key the second time and the display shows the 200th data saved in address 12. Press MODE key to exit P5-13. Press SET key the first time and the display shows the 300th data saved in address 13. Press MODE key to exit P5-13. Please note that when using P5-13 to read data each time the address of P5-11 will increase 1 automatically. This indicates that using P5-13 is reading consecutive data. However, when using P5-12 to read data and the address of P5-11 remains the same, it indicates that using P5-12 is not reading consecutive data. The operation steps for reading or writing data through communication are similar to the steps when using a keypad. The functions of P5-12 and P5-13 are also the same.

What is low-frequency vibration? How can I suppress i t?

If the stiffness of the mechanical system is not sufficient after the positioning command is completed, continuous vibration of the mechanical system may still occur even when the motor has nearly stopped. We called this kind of vibration “low-frequency vibration”. At this time, you can use the low-frequency vibration suppression function to minimize the vibration at the machine edges. The range of frequency is from 1.0 to 100.0Hz. Please note that low-frequency vibration suppression is available only in ASDA-A2 series servo drives. There are two modes, Auto and Manual, that you can select: (1) Auto mode If it is difficult for you to know the point where the low-frequency vibration occurs, we recommend that you select auto mode to find the low-frequency of the mechanical vibration automatically. When P1-29 is set to 1, the system disables the filter function and finds the low vibration frequency automatically. After the detected frequency becomes fixed and stable, the system sets P1-29 to 0, saves the first measured low-frequency value automatically into P1-25 and sets P1-26 to 1. Next, the system saves the second measured low-frequency value automatically into P1-27 and sets P1-28 to 1. If any low-frequency vibration occurs after P1-29 is automatically set to 0, check if the function of P1-26 or P1-28 is enabled or not. When P1-26 or P1-28 is set to 0, it indicates that there is no vibration frequency detected. Please decrease value set in P1-30 (Low-frequency Vibration Detection Level) and set P1-29 to 1 to find the low-frequency vibration again. (2) Manual mode There are two groups of low-frequency vibration suppression parameters. The first group is P1-25 and P1-26 and the second group is P1-27 and P1-28. Using these parameters you can suppress the vibration of two different low frequencies and improve system performance. P1-25 and P1-26 set the vibration frequency, and P1-26 and P1-28 set the frequency response after the filter is used (after the signals are filtered). When values set in P1-26 and P1-28 are higher, the frequency response is faster. However, if the values are too high, they may affect the motor operation and the motor might not run smoothly. The default settings for P1-26 and P1-28 are 0, indicating that the low-frequency vibration suppression is disabled.

When do you need to use a regenerative resistor?

When a fault, ALE05 (Regeneration Error) is detected on the servo drive, it indicates that regenerative power has returned from the load to the servo drive and it exceeds the processing capacity of the servo drive. This power will be transmitted into the capacitance of the DC Bus and result in rising voltage. When the voltage rises too high, the servo system needs to dissipate the extra energy by using a regenerative resistor. The ASDA-A2 series servo drive provides a built-in regenerative resistor which is equipped as standard. Users can also connect an external regenerative resistor if more regenerative capacity is needed. The following table shows the specifications of the servo drive's built-in regenerative resistor and the amount of regenerative power (average value) that it can process. ASDA-A2 220V Series

ASDA-A2 400V Series

Please pay close attention to the following notes when using a regenerative resistor. 1.Make sure the settings of resistance (parameter P1-52) and capacity (parameter P1-53) are set correctly. 2.When installing an external regenerative resistor, make sure that its resistance value is the same as the resistance of the built-in regenerative resistor. If combining multiple small-capacity regenerative resistors in parallel to increase the regenerative resistor capacity, make sure that the resistance value of the regenerative resistor complies with the specifications listed in the table above. 3.In general, when the amount of regenerative power (average value) that can be processed is used at or below the rated load ratio, the resistance temperature will increase to 120°C or higher (when regeneration occurs continuously). For safety reasons, forced air cooling is a good way to reduce the temperature of the regenerative resistors. We also recommend using regenerative resistors with thermal switches. As for the load characteristics of the regenerative resistors, please check with the manufacturer. 4.When using an external regenerative resistor, connect it to P and C, and make sure the circuit between P and D is open. We recommend using external regenerative resistors with resistance values that follow the table above (Specifications of Built-in Regenerative Resistors).

How does regenerative resistor affect the servo drive?

A regenerative resistor is used to discharge the regenerative power returned from the motor to the servo drive which is generated when the servo motor runs and stops a load with a large amount of inertia frequently. This regenerative power is transmitted into the capacitance of DC bus, resulting in the rise of voltage. When the voltage rises to a certain high level, the servo drive will need to dissipate the extra energy by using a regenerative resistor. In general, when the capacity of the regenerative power is small, there is no need to install a regenerative resistor. Use the regenerative resistor when: 1.A regeneration error (ALE05) is detected on the servo drive during the operation. 2.The DC bus voltage exceeds 370V or the output torque of the servo motor exceeds 100% constantly.

When using ASDA-A2 series servo system, how can I se t up proper electronic gear ratio to complete the pulse output positioning?

Firstly, calculate the length that the servo motor rotates one revolution (circumference). Then use parameters P1-44 and P1-45 to determine the proper electronic gear ratio. For example, as the encoder pulse per revolution of ASDA-A2 series is 1,280,000 p/rev, and if you want to make ASDA-A2 series rotate one revolution by making the motion controller (PLC) send out 30,000 pulses, set P1-44 to 128 and P1-45 to 3 to achieve the positioning.

How to suppress the mechanical resonance by using ASD A-A2 series servo system?

ASDA-A2 series has built-in resonance suppression function (two groups of auto notch filters and one group of manual notch filter) to suppress the mechanical resonance effectively. When the mechanical resonance occurs, the user can set P2-47 to 1 (Auto Resonance Suppression Mode) to detect the existing resonance frequency first. After the resonance frequency is found, ASDA-A2 series will execute the suppression immediately. In the meanwhile, a

noise may be heard shortly. After the noise has disappeared, it indicates that the suppression is completed and the system will memorize the resonance frequency into parameters P2-43, P2-44 and P2-45, P2-46 automatically. If only one resonance frequency is found, the system will memorize it into P2-43 and P2-44. When the mechanical resonance is reduced, the user needs to set P2-47 to 0 to disable the resonance suppression function. If the resonance conditions can not be eliminated after two groups of auto notch filters are used, we recommend the user to use the 3rd group of notch filter, i.e. the manual notch filter P2-23, P2-24. To use manual notch filter function, activate ASDA-A2 Soft configuration software first. Then, select Tools > Data Scope function from the menu bar to monitor the motor current, measure the current waveform and calculate the cycle between two resonance points. Next, take the reciprocal of the value of the cycle and the calculation result is the resonance frequency. Then, enter the value of the resonance frequency into P2-23 and set appropriate resonant attenuation in P2-24 to suppress the mechanical resonance. In general, the resonance attenuation is set to 5dB. The user can increase the value by 2dB at every time until the mechanical resonance is eliminated.

In the application of electronic equipment, if an abnor mal operation occurs in the process of manufacturing, the servo system may generate an excessive current or torque which would damage the product. How to prevent such problem?

ASDA-A2 series servo system offers a built-in motor protection function which allows the user to define the threshold of output torque (parameter P1-57) and the time of duration (parameter P1-58) freely. The user can observe the maximum output current and torque value during the normal operation and decide the threshold of output torque and the time of duration. When the setting value of P1-57 is reached after a period of time set by P1-58, the fault AL030 will be activated to warn the user of the excessive torque problem. At this time, the servo drive will turn off (Servo Off) and stop outputting torque value so as not to damage the product or the system.

What is PUU provided in ASDA-A2 series?

The PUU (Pulse of User Unit) is a unit which is scaled by the electronic gear. This will bring out an advantage, and that is “YOU SEE WHAT YOU COMMAND”. For example, if you send 10000 PUU for command and you can read from the feedback 10000 PUU by ignoring the E-Gear Ratio and vise versa. Please refer to the figure below for more explanation.

In general, people always consider that if using servo motors of 2kW power rating which have the same load, the same inertia (for cutter system) and the same rotatio n speed, there are only advantages of using high inert ia ratio servo motor. However, actually, in the process of the experiment, we found that if the servo drive for cu tter system is not changed, when servo motor of frame size 130mm and 2kW power rating is used, the load ratio is about 120% to 140%, and the servo motor will begin to o verheat when the load inertia ratio reaches 1%. As the motor is always overheated, we changed the motor and u se the motor of frame size 180mm and the same 2kW power rating. As a result, as long as the motor speed reaches 800r/min, the alarm code, ALE02 (overvoltage) or ALE05 (regeneration error) will occur. The torque of these two motors is the same, but the speed limit of the motor of frame size 130mm is 1200r/min. From this example, it can be seen that a higher inerti a ratio is not always better. So, what kind of applicatio n will be affected by inertia ratio and what kind of applicatio n will be affected by torque? How does inertia ratio an d torque effect on machine? (part 2)

2. Additional Information: Usually, the cutter shaft of the packing machine is running at a variable speed, and the speed is changed with the cutting length ratio (product length/ circumference of cutter unit). The lower the cutting length ratio is, the greater the change of the cutter speed is. The connection with the system inertia: The person who is fatter has the worse flexibility. By the same token, it is more difficult to perform acceleration and deceleration when the system inertia is large. This also indicates that a larger current will be required for acceleration (lead to alarm of AL006 easily) and a larger regenerative power will be generated for deceleration (lead to alarm of AL005 easily). Solution: 1)Replace with the low-inertia motor. 2)Add the external regenerative resistor to consume more regenerative power. 3)Connect DC bus in parallel to get a larger system capacitance (It is not recommended to use this method now). 4)Replace with cutters that have different diameters to fit the different product length so that the cutting length ratio will be closed to 1, which is able to smooth the acceleration and deceleration. 5)Adjust the E-cam curve to get a smooth acceleration and deceleration (E-cam function is available in firmware V1.029 sub02 or later version). 3. JL: Load Inertia; JM: Motor Inertia 1). When the load inertia ratio is lower, the working efficiency will be improved. However, when JL / JM < 3, it doesn’t need to increase the value of JM especially to reduce the value of JL / JM. Increasing the value of JM will lead to a higher value of JL + JM and doing this is not good for acceleration or deceleration. 2). When the connecting mechanical system is a soft mechanism (such as belt, steel wire, etc.), if the load inertia ratio is too large (>10) and the system requires rapid acceleration and deceleration, the system performance will be degraded, such as overshoot. When the mechanical system is driven by a 4m-length belt, it’s better to use the motor with high inertia. 3). When the mechanical system is connected in vertically or the stiffness of the mechanical system is extremely high, the motor shaft and the load can be regarded as a whole. i)When the application requires the acceleration/deceleration operation, and stop/run operation very frequently, a low-inertia motor is better. However, if JL / JM >5, using a low-inertia motor will make no difference. ii)If the application requires high stability at low-speed, and good anti-interference ability for processing as well, a high-inertia motor is better.

In general, people always consider that if using servo motors of 2kW power rating which have the same load, the same inertia (for cutter system) and the same rotatio n speed, there are only advantages of using high inert ia ratio servo motor. However, actually, in the process of the experiment, we found that if the servo drive for cu tter system is not changed, when servo motor of frame size 130mm and 2kW power rating is used, the load ratio is about 120% to 140%, and the servo motor will begin to o verheat when the load inertia ratio reaches 1%. As the motor is always overheated, we changed the motor and u se the motor of frame size 180mm and the same 2kW power rating. As a result, as long as the motor speed reaches 800r/min, the alarm code, ALE02 (overvoltage) or ALE05 (regeneration error) will occur. The torque of these two motors is the same, but the speed limit of the motor of frame size 130mm is 1200r/min. From this example, it can be seen that a higher inerti a ratio is not always better. So, what kind of applicatio n will be affected by inertia ratio and what kind of applicatio n will be affected by torque? How does inertia ratio an d torque effect on machine? (part 1)

1. High-inertia motor is not always better and the low-inertia motor is not always worse. It depends on application. T= I x α (Torque = Inertia x Angular Acceleration) P= T x ω (Power Rating = Torque x Angular Acceleration)

P = I x α x ω Therefore, with the same power, if the inertia is increased, the acceleration must be decreased which means the characteristics of the acceleration and deceleration are worse. Of course, the angular speed will be changed, too. Here, we assume that the operating speed remains the same. “I “ is a fixed value. After a system (such as flying shear system, the flying shear will not change. But if it is used for conveyer belt, the inertia will change. When the goods on the belt become more, the drag force should be strengthened.) is set, the users can use the formula (T=I*α) to estimate the acceleration and deceleration, and the required torque. α = (target speed- initial speed)/ (needed time from initial speed to target speed) If a system needs the torque of 1 N-m, and using either high-inertia or low-inertia motor is able to achieve the performance, the low-inertia motor is a better choice if a quick response and a high speed are desired. Therefore, it can be easy to explain why low-inertia motor is better by the above formula. Because the rotor inertia of the low-inertia motor is lower and the rotor is lighter also, so when the motor stops, the regenerative power will be less. By the same logic, hitting the wall at the same speed, the power of the fat person is bigger than the thin person’s. In conclusion, if the application requires quick response and good acceleration and deceleration characteristics, the low-inertia motor is more applicable (if the torque force is enough). If the application needs large torque, such as heavy lifting system, the high-inertia motor would be more suitable.

What is the meaning of the symbol marked after paramete r code? What should the user pay attention to it?

The explanation of symbols marked after parameter codes are shown as the following. Please pay close attention to it before setting these parameters. (★) Read-only register, such as P0-00, P0-01, P4-00. (▲) Parameter cannot be set when Servo On (when the servo drive is enabled). (●) Parameter is effective only after the servo drive is restarted (after switching power off and on), such as P1-01. (■) Parameter setting values are not retained when power is off.

How many groups of Delta servo drive parameters? What a re Delta servo drive parameter groups?

There are five groups for drive parameters. They are: Group 0: Monitor parameter (example: P0-xx) Group 1: Basic parameter (example: P1-xx) Group 2: Extension parameter (example: P2-xx) Group 3: Communication parameter (example: P3-xx) Group 4: Diagnosis parameter (example: P4-xx)

How to choose adequate external regenerative resistor? If there is a simple method for the user to select the regenerative resistor conveniently?

The users can select the adequate regenerative resistors according to the allowable frequency required by actual operation and the allowable frequency when the servo motor runs without load. The allowable frequency when the servo motor run without load is the maximum frequency that can be operated during continuous operation when servo motor accelerate from 0rpm to rated speed and decelerate from rated speed down to 0rpm. The allowable frequencies when the servo motor run without load are summarized in the following table. When the servo motor runs with load, the allowable frequency will change according to the changes of the load inertia and rotation speed. Use the following equation to calculate the allowable frequency. m = load/motor inertia ratio The users can select the adequate regenerative resistors according to the allowable frequency by referring to the table below:

What is regenerative resistor? How to connect a regene rative resistor? What kind of situation that needs to use the regenerative resistor?

When the output torque of servo motor in reverse direction of motor rotation speed, it indicates that there is a regenerative power returned from the load to the servo drive. This power will be transmitted into the capacitance of DC Bus and result in rising voltage. When the voltage has risen to some high voltage, the servo system needs to dissipate the extra energy by using a regenerative resistor. ASDA-A series servo drive provides a built-in regenerative resistor and the users also can connect to external regenerative resistor if more regenerative capacity is needed. When using an external regenerative resistor, connect it to P and C, and make sure the circuit between P and D is open. When using a built-in regenerative resistor, connect it to P and D, and ensure an open circuit between P and C. When the regenerative power exceeds the processing capacity of the servo drive, the fault, ALE05 may occur. At this time, please install an external regenerative resistor.

Why the ratio of load Inertia to servo motor inertia th at is adjusted by the customer will be not the same a s the actual ratio value?

Maybe the following conditions are not met. When estimating the ratio of load Inertia to servo motor inertia, please satisfy the following conditions in order to ensure the correct ratio of load Inertia to servo motor inertia. 1) The accel. and decel. time for reaching 2000rpm should be 1sec. and below. 2) The rotation speed should be kept as 200rpm and above. 3) The load inertia cannot exceed 100-multiple of motor inertia. 4) The outside force cannot too much and the change of the ratio of load inertia to servo motor inertia cannot be excessive. 5) In AutoMode (when setting parameter P2-32 to 3 or 5), the system will stop to measure the load inertia value.

What is stiffness?

Stiffness is a measure of how well a servo motor can hold a position when some outside force is trying to move it. We can say it is a strength that is against the low frequency external force.

What parameters to use when the user select internal auto running mode?

Please refer to the following table. When the setting value of the dwell time register listed above is set to zero (0), the relative position will be ignored.

In Position Control mode, how many types of external p ulse inputs?

There are three types of external pulse inputs, including PULSE+SIGN, CW+CCW, and AB phase pulse? 1) Pulse + Direction: operation speed is determined by the frequency of the first pulse command. Second pulse input will decide Forward or Reverse command, high voltage for forward and low voltage for reverse. 2) CW+CCW: operation speed is determined by the frequency of the pulse command. Forward command is decided by the first command input and reverse command is by second command input. 3) AB phase pulse (encoder): operation speed is determined by the frequency of pulse command x1, x2, or x4. When first pulse command leads before the second one, the command will be forward. When second pulse command leads before the first one, the command will be reverse.

What is the meaning of “Ratio of Load Inertia to Servo M otor Inertia”?

Ratio of load inertia to servo motor inertia: (J_load /J_motor) J_load: Load inertia J_motor: Motor rotor inertia When selecting the servo drives and motors that the user want to use, the user not only should consider the motor torque and rated speed, but also need to know the ratio of load inertia to servo motor inertia. Then, the user can select the proper motor that is correctly matched for the servo drive according to the actual requirements of the connected machine (load condition) operation and the quality and quantity requirements for materials processing and manufacturing. When perform tuning and trial run, setting (J_load /J_motor) correctly is the most important / essential for optimizing the performance of the mechanical system and servo system and make them work efficiently.

How to change the control mode of Delta servo drive?

Answers: The user can use parameter P1-01 to change the control mode (see the following table). After the setting is completed, cut the power off and restart the servo drive again. The new control mode will be valid after drive off / on action. Pt: Position control mode (command from external signal) Pr: Position control mode (command from internal signal) S: Speed control mode (external signal / internal signal) T: Torque control mode (external signal / internal signal) Sz: Zero speed / internal speed command Tz: Zero torque / internal torque command