ABB frequency converter is a widely used equipment in the field of industrial automation. It can adjust the speed of the motor according to actual needs, thereby achieving energy-saving and improving production efficiency. In practical applications, it is sometimes necessary to remotely control the frequency converter to achieve more flexible control methods. This article will introduce the frequency setting method for ABB frequency converters in remote mode.

Understand the basic concepts of ABB frequency converters
Before setting the remote mode frequency, we need to first understand some basic concepts about ABB frequency converters. ABB frequency converter is a device that converts AC power into adjustable frequency, which adjusts the motor speed by changing the power supply frequency of the motor. The frequency converter is mainly composed of rectifier, intermediate circuit, inverter, and control circuit.
1.1 Rectifiers: Convert alternating current to direct current.

1.2 Intermediate circuit: stores and smoothes direct current.

1.3 Inverter: Convert direct current into adjustable frequency alternating current.

1.4 Control circuit: Control the frequency converter according to actual needs.

Basic concepts of remote mode
Remote mode refers to the method of controlling a frequency converter through external signals or communication interfaces. In remote mode, the frequency converter can adjust the output frequency based on external signals or instructions received through communication interfaces, thereby achieving the regulation of motor speed.

Method for setting remote mode
3.1 Hardware Connection

Before setting up remote mode, it is necessary to complete the hardware connection first. According to actual needs, the following connection methods can be selected:

3.1.1 Analog signal input: Input external signals to the frequency converter through an analog signal input interface (such as 0-10V or 4-20mA).

3.1.2 Communication Interface: Connect the frequency converter to devices such as the upper computer or PLC through communication interfaces (such as RS485, Modbus, etc.).

3.1.3 Fieldbus: Connect the frequency converter to the upper computer or PLC equipment through fieldbus (such as Profibus, DeviceNet, etc.).

3.2 Software Settings

After completing the hardware connection, it is necessary to perform software settings on the frequency converter to achieve frequency control in remote mode.

3.2.1 Setting Control Mode

In the parameter settings of the frequency converter, select the “Control Mode” option and set it to “Remote Control” or “Communication Control”.

3.2.2 Setting frequency setting method

In the parameter settings of the frequency converter, select the “frequency setting method” option and choose the corresponding setting method according to actual needs, such as “analog signal input”, “communication interface” or “fieldbus”.

3.2.3 Setting frequency setting range

In the parameter settings of the frequency converter, select the “Frequency Setting Range” option and set the upper and lower limits of the frequency in remote mode. In general, the upper and lower limits should be set according to the rated frequency and actual requirements of the motor.

3.2.4 Setting Communication Parameters

If remote control is chosen through communication interface or fieldbus, corresponding communication parameters need to be set, such as baud rate, data bits, stop bits, verification method, etc.

3.3 Setting of external signals or communication instructions

After completing hardware connections and software settings, external signals or communication instructions need to be set according to actual needs.

3.3.1 Analog signal input

If remote control is chosen through analog signal input, the input range of external signals needs to be set. In general, the input range should correspond to the frequency setting range of the frequency converter.

3.3.2 Communication Interface

If remote control is chosen through a communication interface, corresponding communication instructions need to be set according to the communication protocol (such as Modbus). Communication instructions typically include information such as device address, function code, register address, and data length.

3.3.3 Fieldbus

If remote control is chosen through fieldbus, corresponding communication instructions need to be set according to the fieldbus protocol (such as Profibus). Fieldbus instructions typically include information such as device address, function code, data block address, and data length.

Example of Frequency Control in Remote Mode
4.1 Example of Analog Signal Input Control

Assuming we use a 0-10V analog signal input to control the output frequency of the frequency converter. Firstly, connect the analog signal input interface to an external signal source, such as the analog output module of a PLC. Then, in the parameter settings of the frequency converter, set the control mode to “remote control”, the frequency setting method to “analog signal input”, and the frequency setting range to 0-50Hz corresponding to 0-10V. Finally, by adjusting the output voltage of the external signal source, the output frequency of the frequency converter can be adjusted.

4.2 Example of Communication Interface Control

Assuming we use Modbus communication protocol to control the output frequency of the frequency converter through RS485 interface. Firstly, connect the frequency converter to the upper computer or PLC equipment through RS485 interface. Then, in the parameter settings of the frequency converter, set the control mode to “communication control”, the frequency setting method to “communication interface”, and the communication parameters to the baud rate, data bits, stop bits, and verification method corresponding to the upper computer or PLC equipment. Finally, by sending Modbus communication commands, the output frequency of the frequency converter can be adjusted.