Inverter debugging steps - Solutions - Huaqiang Electronic Network

Brand AVX TPSE226M035R0125 Low impedance tantalum capacitor AVX 22

Electronic scale crystal oscillator 3.2*2.5mm 3225 16M (16.000MHZ) 12PF 10PPM 20PPM 30PPM

Photocoupler

The inverter can be successfully applied to various loads to obtain long-term stable operation. On-site debugging is critical and must be carried out according to the corresponding steps.
1. Check before the no-load power-on of the inverter (1) Connect the power input terminal of the inverter to the power supply through the leakage protection switch;
(2) Ground the ground terminal of the inverter;
(3) Confirm whether the voltage frequency level of the brand name tag of the inverter matches the grid, and send power after error;
(4) The main contactor is closed, the fan is running, and the input power supply voltage is tested in the standard specification with the multimeter ac file;
(5) Familiar with the operating keyboard keys of the inverter;
Take Pu Chuan as an example: fwd (forward run key: let the drive run in the forward direction), rev (reverse run key: let the drive run backwards), esc/displ (exit/display key: exit the data change of the function item, The fault status exits, exits the submenu or enters the status display menu by the function item menu), stop/reset (stop reset key: stop the drive, abnormal reset, fault confirmation), prg (parameter setting/shift key), set (Parameter setting key: Save the value after modification, change the monitoring target in the monitoring state), â–² (Parameter change/addition and subtraction keys: set value and parameter change use, change the given frequency in the monitor state), jog (jog operation) Key: Press the inching operation to release the stop operation. The definitions of the different inverter operation keys are basically the same.
(6) Run the inverter to 50hz, and test the three-phase output voltage balance of the inverter u, v, w;
(7) After the power failure is completely not displayed, connect the motor cable.
2. Inverter with motor no-load operation (1) Set the basic rated parameters of the motor, and comprehensively consider the operating current of the inverter.
(2) Set the maximum output frequency, fundamental frequency and set torque characteristics of the inverter. The v/f type selection includes items such as the highest frequency, base frequency, and torque type. The highest frequency is the highest frequency that the inverter-motor system can operate. Since the maximum frequency of the inverter itself may be high, when the maximum frequency allowed by the motor is lower than the highest frequency of the inverter, it should be set according to the requirements of the motor and its load. set. The basic frequency is the dividing line between the inverter for constant power control and constant torque control of the motor, which should be set according to the rated voltage of the motor. The torque type refers to whether the load is a constant torque load or a variable torque load. The user selects one of the types according to the v/f type map and load characteristics in the inverter's instruction manual. The general-purpose inverters are equipped with multiple v/f curves for the user to select. The user should select the appropriate v/f curve according to the nature of the load. In order to improve the low-speed performance of the inverter when starting, the torque output from the motor can meet the requirements of the production load start-up, and the starting torque should be adjusted. In the asynchronous motor variable frequency speed control system, the torque control is more complicated. In the low frequency band, since the influence of resistance and leakage reactance cannot be ignored, if the v/f is kept constant, the magnetic flux will decrease, thereby reducing the output torque of the motor. For this reason, the voltage is appropriately compensated at the low frequency band to increase the torque. Generally, the inverter is manually compensated by the user. The general transmission inverter provides users with two options: 42 v/f lifting modes and automatic torque boosting.
(3) The frequency setting and running control of the inverter are all keyboard mode. Press the running key and stop key to observe whether the motor can start and stop normally.
(4) Familiar with the protection code when the inverter runs fault, observe the factory value of the thermal protection relay, observe the setting value of the overload protection, and modify it if necessary. The user of the inverter can set the electronic thermal relay function of the inverter according to the instruction manual of the inverter. The threshold of an electronic thermal relay is defined as the ratio of the rated current of both the motor and the frequency converter, usually expressed as a percentage. When the output current of the inverter exceeds its allowable current, the overcurrent protection of the inverter will cut off the output of the inverter. Therefore, the maximum value of the threshold current of the inverter electronic thermal relay does not exceed the maximum allowable output current of the inverter.
(5) Run the inverter to full frequency, test the output voltage and current to see if it matches the value monitored by the keyboard.
3. Load test operation (1) Manually operate the operation stop button of the inverter panel, observe the motor running stop process and monitor the inverter to see if there is any abnormality.
(2) If the inverter has overcurrent protection during the start and stop of the motor, the acceleration and deceleration time should be reset. The acceleration of the motor during acceleration and deceleration depends on the acceleration torque, and the frequency change rate of the inverter during start and brake is set by the user. If the motor's moment of inertia or motor load changes, when the speed is increased or decelerated according to the preset frequency change rate, there may be insufficient acceleration torque, which may cause the motor to stall, that is, the motor speed is not in harmony with the inverter output frequency, resulting in Current or over voltage. Therefore, it is necessary to set the acceleration and deceleration time according to the motor inertia and load, so that the frequency change rate of the inverter can be coordinated with the motor speed change rate. The reason for checking whether this setting is reasonable is to first select the acceleration and deceleration time according to experience, and if there is overcurrent during the starting process, the acceleration time can be extended appropriately; if overcurrent occurs during braking, Prolong the deceleration time appropriately. On the other hand, the acceleration and deceleration time should not be set too long, and the long time will affect the production efficiency, especially in the operating conditions of frequent start and brake.
(3) If the inverter still has an operation fault, try to increase the protection value of the maximum current, but the protection cannot be canceled, and at least 10% to 20% of the protection margin should be left.
(4) If the inverter operation failure still occurs, replace the inverter with a larger power.
(5) If the inverter drives the motor to reach the preset speed during the startup process, there may be two cases:
● The system generates mechanical resonance and can be judged from the sound of the motor running. By setting the frequency jump value, you can avoid the resonance point. Generally, the inverter can set three-level jump point. When the inverter controlled by v/f drives the asynchronous motor, the current and speed of the motor will oscillate in some frequency segments. In severe cases, the system cannot run, and even the overcurrent protection occurs during the acceleration process, so the motor cannot start normally. It is more serious when the light load or the moment of inertia is small. The common inverters are equipped with a frequency jump function. The user can set the jump point and the jump width on the v/f curve according to the frequency point at which the system oscillates. These frequency segments can be automatically skipped when the motor accelerates to ensure that the system can operate normally.
● The torque output capability of the motor is not enough. The factory parameters of different brands of inverters are different. Under the same conditions, the load capacity is different. The load control capability of the motor may be different due to different inverter control methods. The output efficiency is different, resulting in different load capacity. In this case, the value of the torque boost amount can be increased. If it is not available, the manual torque boost function can be used. Do not set too large, and the temperature rise of the motor will increase. For fan and pump loads, the curve for the torque reduction should be reduced.
4. After the system debugging setting of the inverter and the host computer is completed, if there is a host computer in the system, connect the control line of the inverter directly to the control line of the host computer, and change the operation mode of the inverter to terminal control. According to the needs of the host computer system, set the range of the inverter receiving frequency signal terminal to 0~5v or 0~10v, and the response speed of the inverter to sample the analog frequency signal. If an additional monitoring head is required, select the monitoring amount of the analog output and adjust the range of the inverter output monitoring terminal.