Detailed interpretation of the inverter control start/stop, forward/reverse circuit diagram

 The control of the frequency converter is nothing more than the basic logic of start, stop, forward rotation, reverse rotation, and speed regulation. These logics basically require that the level state is valid, not the rising edge, so the button switch is used to control the frequency converter. When installing a switch, it is generally necessary to use a self-protection button switch. If it is not a self-protection form, an intermediate relay needs to be added for self-protection.

1. Single switch start and stop

 When a single switch is used to start and stop the inverter, the inverter can start by giving the RUN terminal a high level. When the switch is turned off, it is equivalent to the RUN terminal becoming a low level, and the inverter stops running.

In this case, a self-protection button switch can be used to meet the start and stop control of the frequency converter. The extra switch can be used for fault reset and connected to RST. Of course, it is more ideal to use a non-maintaining switch. When the frequency converter When there is a fault, press the reset switch to clear the fault of the inverter. Because there is no separate potentiometer setting, the frequency can be set through the operation panel at this time. Of course, the above logic can also be completed through a logic controller such as a PLC.

2.Double switches realize forward and reverse start and stop. 

In some cases, it is necessary to control the forward and reverse rotation of the frequency converter. Although the AC asynchronous motor can be reversed by turning any two phase lines at the output end of the frequency converter, the operation is more troublesome and laborious. The frequency converters are equipped with reverse direct start control function.

For example, if a switch is connected to the forward rotation terminal of the frequency converter (some are FWD, here is DI1), then the frequency converter will rotate forward. Of course, the switch must be of the maintained type. When the switch is disconnected, the frequency converter will stop directly. The article comes from the Internet and is intended to be shared with fans. If there is any infringement, please contact us to delete it! Similarly, when another switch is connected to the reverse terminal of the frequency converter (some are REV, here is DI2), the frequency converter will reverse direction. The switch must also be maintained. When the switch is disconnected, the frequency converter will stop running. If there is no external potentiometer, the frequency value of the inverter can also be set through the panel.

3.One switch controls start and stop, and the other controls the speed setting.

As mentioned above, one switch controls the start and stop of the inverter. The other switch can actually be used for speed setting, the simplest one, such as jog. Control, some frequency converters, especially European ones, can set multi-function terminals through internal parameters, and a switch can be set to jog mode, so that the switch can control the frequency converter to work in the jog state, and the inverter in the jog state It usually runs at 5% speed. Of course, this value can also be modified through the panel.

You can also use the multi-speed function port or UP/DOWN to set the speed. The essence is the same as the jog mode. No matter what method is used to control the inverter through the switch, the essence is to give a certain high and low level to the I/O port of the inverter. If the inverter does not move, just measure the corresponding I/O port with a multimeter to judge the level. If the signal is normal, you can know whether the line is connected correctly, and then set the function of the port according to the instruction manual. The control of the inverter is nothing more than starting, stopping, forward rotation, reverse rotation, and speed adjustment. Logic, these logics basically require that the level state is valid, not the rising edge. Therefore, when using a push button switch to control the inverter, it is generally necessary to use a self-protection push button switch to complete. If it is not a self-protection form, additional Add an intermediate relay for self-protection.