Analysis of common problems of Schneider inverter

1. Use the analog output port to indicate the motor frequency, when the motor frequency is 50Hz, why is the output only 16mA?

Because the maximum output frequency parameter of the inverter is "TFR", the factory default value is 60Hz. So when the inverter output is 50Hz, the analog output is 16mA. In this case, just change the "TFR" parameter to 50Hz

2. Does my company have an inverter to control the single-phase communication motor?

No. Although there is a single-phase power input inverter, its output is three-phase, which can only be used to control the three-phase motor.

Analysis of common problems of Schneider inverter

Analysis of common problems of Schneider inverter

3. Why is the inverter used for fan and pump loads to save energy?

According to the basic law of fluid mechanics, it can be known that the fan pump load is a typical square rotation load, and its main characteristics are: the speed n and the torque T and the load power P have the following relationship: T∝n2, P∝n3. That is, the torque is proportional to the square of the speed, and the power is proportional to the cube of the speed. Usually the fan pump load is mostly selected according to the amount of full load operation, and most of the time in practical application is not in full load condition, so as long as the uniform speed drops slightly, the load power will drop very quickly, and then achieve energy saving. But when choosing the motor direct starting method, because the speed can not be adjusted, the wind shield, the valve are commonly used to adjust the air volume or the flow rate, so not only causes the waste of power but also causes the power grid impact and the vibration and water hammer phenomenon of the equipment because of the excessive starting current, when the frequency converter is selected to regulate the speed, the speed can be conveniently controlled according to the practical process requirements. For example: when the motor speed is 80% of the rated speed, the load power is the cubic of the rated power (80%), that is, about 50%. In this way, it can be seen that the speed is reduced by 20%, and the energy saving is more than 40%. Together, closed-loop constant pressure control can be easily completed, and the energy-saving efficiency will be further improved. The use of frequency converter avoids the impact on the power grid when starting, reduces the equipment failure rate, eliminates the vibration and water hammer phenomenon, prolongs the service life of the equipment, and also reduces the capacity requirements and reactive power loss of the power grid.

4. What is the basic equipment of the standard products of ATV71/61 inverter powered by three-phase 380V power supply?

Chinese LCD screen: 15KW below is optional, 15KW or more is standard. DC incoming reactor: 0.75kw-15kw without built-in DC reactor, optional as an accessory when needed; The standard product DC reactor of more than 90KW is handed over with the inverter, and the user needs to assemble according to the device diagram, if the DC reactor is not ordered, add a "D" at the end of the type; 18.5KW-75KW has been built-in. EMC input filters: All have built-in EMC.

5. How to complete the control of ATV38 and ATV58 through the operation panel?

First, in the control menu, set "LCC" to "YES" (panel operation); Enter the "LFR" parameter in the adjustment menu, press the up and down keys to adjust the given value, and complete the control of the inverter.

6. How to communicate between multiple ATV71/61 inverters connected to the same bus and a graphic display terminal? The [Communication] menu→ [Network MODBUS] → [MODBUS Address] (ADD) set the address of each inverter. When multiple inverters are connected to the same display terminal, the terminal will actively display the inverter address.　　 It is possible to visit all menus in multi-point form, but does not allow the graphical display of the terminal to control the inverter.

7. In the application of motor reactors, why is the interval required for shielded cables shorter than that of unshielded cables?

Because parasitic capacitance is generated between the shield layer and the conductor of the shielded cable, the cable should not be too long.

8. The main circuit of the high-power ATV71/61 inverter has been energized, why does NLP (main circuit not energized) sometimes prompt it?

This is because there is no short wiring between the terminals PO and PA/+ connected to the DC reactor, and the main circuit cannot be supplied with power. The short-wired of the frequency conversion less than 90KW has been connected when leaving the factory, and the frequency conversion required by the customer is short-circuited by the customer when the frequency conversion is greater than or equal to 90KW.

9. What is the function of the inverter DC reactor?

Reduce the higher harmonic disturbance of the input current and improve the power factor of the input power supply.

10. What is the significance of forced local operation of the inverter?

Local operation refers to the control of the terminal or display module by the inverter, and the corresponding communication control. If you want to switch between communication control and local operation, you must equip a logical input terminal with "FLO", that is, force local operation.　　 When the input is condition 1, the local operation is forced; When the input is condition 0, the communication control is effective.

Analysis of common problems of Schneider inverter

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