Faults and treatments in the use of the inverter - News - Global IC Trade Starts Here Free Join

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1. The frequency of the inverter does not reach the normal working frequency (40HZ). A SAMCO-i inverter is controlled by external terminal analog quantity. Once the frequency can only reach 20HZ, the parameters are checked in turn. The highest frequency and upper limit frequency are both 50HZ. No parameter is visible, and the panel is given the frequency immediately. Then the highest frequency can run to 50HZ. From this point of view, the problem lies in the analog input circuit or the original device of the inverter itself. Check the thermal resistance with a multimeter. The linearity is very good, no problem. Finally, the inverter is turned on and found that a chip capacitor is damaged. After replacement, the inverter is replaced. Back to normal.

2, the inverter frequently overcurrent alarm

(1) The parameter setting is incorrect. If the inverter acceleration time setting is too short, the inverter output frequency changes much more than the motor frequency change. When the inverter starts, it trips due to overcurrent.
This fault can be eliminated by adjusting the acceleration time accordingly according to different load conditions.
(2) The output load is short-circuited. If a Fuji inverter starts, it trips. Check that the cable head part of the output side contactor is rusted and loose, and an arc occurs during startup, resulting in protection action.
(3) Damage to the detection circuit will also display a transition alarm. The Hall sensor is affected by environmental factors such as temperature and humidity, and the operating point drifts.
(4) Excessive load may also cause. Such as a Siemens M420 inverter, due to mechanical stuck.
3. A Siemens 6SE7036 inverter trips after a period of time. “F023” is displayed (the inverter exceeds the limit temperature). It is checked because the fan is out of service and the temperature is too high and it trips. Replace the insurance.
4. The LCD panel of the PMU panel of a Siemens 6SE7036 inverter displays the letter “E”. The inverter can't work normally. Pressing the P keyboard and restarting the power supply are invalid. Check the operation manual for no explanation. Check the external 24VDC power supply. When the voltage is low, the inverter returns to normal after changing the power supply.
5, the inverter undervoltage, overvoltage alarm, which is caused by the main power supply; also caused by damage to the detection circuit of the machine.
(1) If the 6SE7036 inverter F008 is faulty (Ud
(2) An overvoltage trip occurs when a SAMCO-I inverter is stopped. There are many setting parameters of the inverter. If the individual parameters are not set properly, the inverter will not work properly. When the overvoltage occurs during shutdown, the main reason is that the deceleration time is too short (if there is no braking resistor and braking unit), the motor speed is greater than the synchronous speed, the rotor electromotive force and current increase, so that the motor is in the power generation state, and the energy of the feedback is changed. The diode connected in parallel with the high-power switch tube flows back to the DC link, so that the DC bus voltage rises, and after the time parameter is adjusted, the fault is eliminated.
6, a Siemens MM3 inverter, often "no reason" to stop. It may be normal to turn it on again. After comparison, it is found that the main contactor is not properly connected after power-on, sometimes it will lose power and jump. It turns out that a filter capacitor from the switching power supply to the contactor is leaking, resulting in a low voltage. If the power supply voltage is too high, it will not be a problem. If the power supply voltage is low, the contactor will not be properly connected. .
7, a nuclear said to use the Siemens M420 inverter, in the course of operation, often suddenly stop, restart, and can run. Check that the inverter's parameter settings are correct. If you suspect that there is a problem with the PROFIBUS-DP line, re-place a PROFIBUS-DP line and the fault still exists. Connected to the programmer to check the start condition of the inverter, all the starting points are impossible to break, only the point between the nuclear called plc and the main PLC communication may be broken. After several days of observation, this point is broken in a short time. It returned to normal, so I used a power-down delay timer to handle this failure.
8. Four 22KW motors were originally started with Y-, and replaced with Fuji inverter. The "U002" overvoltage alarm often appears. Check the incoming line voltage, all within 380±10%, the parameters are normal, normal after reset, but it will not take long before the same fault occurs. Finally, consult the inverter instruction manual, the voltage of Fuji inverter is not set in the parameter setting, and It is set by jumper. After re-jumping, the fault is dealt with.
9. The inverter cannot be on the PROFIBUS-DP network. The red light on the inverter is always on, and several parameters P0700, P0719, P0918, and P1000 of the PROFIBUS-DP on the inverter are checked in turn, which are all correct. Then it can only be a problem with the network cable or network card. For a network card, the problem is solved.
In short, in the common faults of the inverter, large components such as IGBT power modules have few problems, and the proportion of faults caused by their peripheral circuits is large. During routine maintenance, pay attention to check the grid voltage, improve the surrounding environment of the inverter, motor and circuit, periodically remove the dust inside the inverter, check whether the terminals are tight, and minimize the failure rate of the inverter by strengthening equipment management. At the same time, do a good job of fault records, pay attention to the analysis of the load status, operation process, fault phenomenon, etc. of the fault are very important, which is conducive to future work.