In many domestic forums, Panasonic series servo details are downloaded free of charge, so many major and have their own technical staff, are able to solve the general Panasonic servo drive repair work, and the author has collated some of the Panasonic servo drive failure quotation instructions and Processing method for reference.
1, Panasonic digital AC servo system MHMA 2KW, when the test machine is powered on, the motor vibrates and there is a lot of noise, then the driver appears No. 16 alarm, how to solve?
This phenomenon is generally due to the driver’s gain setting is too high, resulting in self-oscillation. Please adjust parameter No.10, No.11 and No.12 to reduce the system gain appropriately. (Refer to the “Instruction Manual” for gain adjustment)
2. When Panasonic AC servo driver is powered up, it will display 22nd alarm. Why?
No. 22 alarm is an encoder fault alarm. The reasons for this are:
A. There is a problem with the encoder wiring: disconnection, short circuit, wrong connection, etc. Please check carefully;
B. There is a problem with the encoder on the motor: Displacement, damage, etc. Please send it to us.
3, Panasonic servo motor running at a very low speed, when fast, slow, like crawling, how to do?
The low-speed crawling phenomenon of the servo motor is generally caused by the low system gain. Please adjust parameters No.10, No.11 and No.12, adjust the system gain appropriately, or run the automatic gain adjustment function of the driver. (Refer to the “Instruction Manual” for gain adjustment)
4. Panasonic AC servo system In position control mode, the control system outputs pulse and direction signals. However, whether it is forward or reverse command, the motor only turns in one direction. Why?
Panasonic AC servo system can receive three kinds of control signals in the position control mode: pulse/direction, forward/backward pulse, A/B orthogonal pulse. The factory setting of the driver is A/B quadrature pulses (No 42 is 0). Change No. 42 to 3 (pulse/direction signal).
5. In the use of Panasonic AC servo system, can I use Servo-ON as the signal to control the motor offline to directly rotate the motor shaft?
Although the motor can be taken offline (in a free state) when the SRV-ON signal is turned off, do not use it to start or stop the motor. Frequent use of it to switch the motor may damage the drive. If you need to implement the offline function, you can use control mode switching to achieve: Assuming the servo system requires position control, you can set the control mode selection parameter No02 to 4, that is, the first mode is the position control, and the second mode is the torque control. . Then use C-MODE to switch the control mode: In the position control, the signal C-MODE is turned on so that the driver works in the first mode (ie, position control); when the need to go offline, the signal C-MODE is closed, When the driver is operated in the second mode (ie, torque control), since the torque command input TRQR is not connected, the motor output torque is zero, thereby achieving offline.
6. The Panasonic AC servo used in the CNC milling machine we developed works under the analog control mode. The position signal is fed back to the computer by the pulse output of the driver. After the machine is installed and debugged, the movement instruction is issued and the motor runs on the fly. What are the reasons?
This phenomenon is caused by the wrong phase sequence of the A/B quadrature signal fed back to the computer by the driver pulse output and the formation of positive feedback. The following methods can be used to handle this phenomenon:
A. Modify the sampling program or algorithm;
B. Reverse the A+ and A- (or B+ and B-) pulse output signals of the driver to change the phase sequence;
C. Modify the driver parameter No.45 to change the phase sequence of its pulse output signal.
7. In a testing device developed by us, Panasonic AC servo system was found to have some interference with our detection device. What should be done to eliminate it?
Because the AC servo driver adopts the principle of the inverter, it is a prominent source of interference in the control and detection system. In order to reduce or eliminate the interference of the servo driver to other electronic devices, generally the following methods can be used:
A. The ground of the driver and motor should be reliably grounded;
B. The driver’s power input plus isolation transformer and filter;
C. Use shielded cables for all control signals and detection signal lines.
The problem of interference is a very difficult problem in the electronic technology. There is no fixed method to eliminate it completely and effectively. Anti-jamming measures are usually found through experience and experimentation.
8, why the servo motor will not lose step?
The servo motor driver receives the feedback signal from the motor encoder and compares it with the command pulse to form a semi-closed-loop control of the position. Therefore, the servo motor will not lose step, and each command pulse can be reliably responded.
9, how to consider Panasonic servo power supply problem?
At present, almost all Japanese-made AC servo motors are three-phase 200V power supply, the domestic power supply standard is different, so it must be resolved as follows:
A. For AC servos up to 750W, the single-phase 220V can be directly connected to the L1 and L3 terminals of the driver.
B. For other types of motors, it is recommended to use a three-phase transformer to convert three-phase 380V to three-phase 200V, and access L1, L2, and L3 of the drive.
10. What should you pay special attention to when installing the servo motor mechanically?
Since each servo motor is equipped with a rotary encoder at the rear end, it is a very delicate and delicate optical device. Excessive impact force will certainly damage it.