E6581315

5.1.MODBUS-RTU transmission format

MODBUS-RTU sends and receives binary data without a frame-synchronizing start code and de- fines the blank time to recognize the start of a frame. MODBUS-RTU decides the data that is first received subsequently as the first byte of a frame after a blank time for 3.5 bytes at the on-going communication speed.

5.1.1. Read command (03)

„ Computer → Inverter *The text size is 8 bytes fixed.

 

 

 

Commu-

Commu-

Number

Number

CRC

CRC

 

(3.5bytes

Inverter

Command

nication

nication

of Data

of Data

(3.5bytes

Blank)

No.

 

No.

No.

Groups

Groups

(low)

(high)

Blank)

 

 

(high)

(low)

(high)

(low)

 

 

 

 

 

 

 

 

 

 

03

 

 

00

01

 

 

 

1) Inverter No.. (1 byte)

:Specify an inverter number between 0 and 247 (00H to F7H).

Command processing will be executed only broadcast communication “0” and with those inverters that match set inverter numbers. Data will not be returned if “0” (broadcast communication) and inverter numbers do not match.

2)

Command (1 byte)

: Set the read command (03H fixed).

3)

Communication No.. (2 bytes)

: Set in the order of high to low numbers.

4)

Number of data groups (2 bytes)

: Set the number of data words 0001 (fixed) in the order of high to low numbers.

5)

CRC (2 bytes)

: Set generation results of CRC in the order of low to high numbers.. For the

 

 

method to generate CRC, see “5.2 CRC Generation.” Note that the setting se-

 

 

quence is reversal to that of others.

„ Inverter → Computer (Normal return) *The text size is 7 bytes fixed.

(3.5bytes

Blank)

Inverter

Command

Number of

Read data

Read data

CRC

CRC

No.

 

Data

(high)

(low)

(low)

(high)

 

03

02

 

 

 

 

(3.5bytes

Blank)

1)

Command (1 byte)

: Read command (03H fixed) will be returned.

2)

Number of data

: A number of data bytes (02H fixed) will be returned.

 

 

transmission to the inverters is 2 bytes and 01H fixed.

 

 

turned by the inverters is 1 byte and 02H fixed.

The number of data groups for Note that the number of data re-

3) Read data (2 bytes) : Returned in the order of read data (high) and (low).

„ Inverter → Computer (Abnormal return) *The text size is 5 bytes fixed.

(3.5bytes

Blank)

Inverter No.

Command

Error Code

CRC

CRC

(low)

(high)

 

 

 

 

83

 

 

 

(3.5bytes

Blank)

1)

Command (1 byte)

: 83H fixed (Read command error) (Command + 80H)

2)

Error code (1 byte)

: See “4.3 Transmission errors.”

„ Example: Reading output frequency (During 60Hz operation)

(Computer → inverter)

01 03

FD 00 00 01 B5 A6

(Inverter → computer)

01 03

02 17 70 B6 50

„Example: Data specification error

(Computer → inverter)

01 03

FD 00 00 02 F5 A7

(Inverter → computer)

01 83

03 01 31

30

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Toshiba VF-AS1 Series, RS485 instruction manual MODBUS-RTU transmission format, Read command, Crc
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RS485, VF-AS1 Series specifications

The Toshiba VF-AS1 Series represents a significant advancement in the realm of variable frequency drives (VFDs), designed for various industrial applications that demand precision, efficiency, and reliability. With support for RS485 communication, the VF-AS1 Series fosters seamless integration into complex automation systems, making it the perfect choice for modern manufacturing environments.

One of the standout features of the Toshiba VF-AS1 Series is its versatile communication capabilities. The built-in RS485 port allows for easy connectivity with a range of devices, including PLCs (Programmable Logic Controllers) and HMIs (Human-Machine Interfaces). This ensures real-time monitoring and control of motor functions, enhancing operational efficiency and data analysis.

The VF-AS1 Series is engineered with advanced control technologies that provide exceptional motor performance. It incorporates vector control algorithms that optimize torque and speed regulation for both standard and permanent magnet motors. This results in precise motor control across a wide range of speeds and load conditions, ensuring optimum performance and energy savings.

Another noteworthy characteristic is its user-friendly interface. The VF-AS1 features a clear LCD display that allows for easy navigation and configuration. This intuitive design minimizes the learning curve for operators and technicians, facilitating quick setup and adjustments. Additionally, the series supports various programming options, catering to both novice users and experienced professionals.

Energy efficiency is a key priority in the design of the VF-AS1 Series. The drives are equipped with energy-saving features that help reduce overall power consumption and operational costs. With built-in sleep modes and dynamic energy feedback, these drives optimize energy usage based on demand, making them suitable for both constant and variable load applications.

In terms of safety and protection, the VF-AS1 Series incorporates various built-in safeguards, including overvoltage, undervoltage, and overcurrent protection. This comprehensive approach to safety not only protects the drive itself but also ensures the longevity of connected equipment.

Overall, the Toshiba VF-AS1 Series, with its robust feature set, advanced technologies, and focus on energy efficiency, proves to be a reliable choice for a wide range of industrial applications. Its integration of RS485 communication allows for enhanced connectivity and control, making it an excellent solution for modern automation needs.
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