AI series instrument V5.0 serial communication interface protocol, support 1200, 2400, 4800, 9600, 19200 and other baud rates, and reduce the average time of upper computer to access one instrument to 0.1 second. The instrument allows up to 101 instruments to be connected on one RS485 communication interface (for reliable communication, more than 60 instruments need to add an RS485 repeater).
About this manual
The AI series meters use an asynchronous serial communication interface that complies with RS232C or RS485 standards. Data format is 1 start bit, 8 data bits, no parity, and 1‑2 stop bits. Supported baud rates range from 1200 to 19200 bit/s, and RS485 can reach distances over 1 km. Up to 101 meters may share a single RS485 line, though a repeater is recommended when more than 60 devices are connected.
Communication commands consist of only read and write instructions, each using 16‑bit hexadecimal codes. Addresses are two‑byte values (00H‑64H) and parameters are identified by one‑byte codes. CRC checksums are calculated by simple integer addition as described, and responses include measurement values, setpoints, output status, and alarm flags. This manual is written in Chinese.
What's inside
- Interface Specifications
- Communication Commands
- Parameter Codes
- Addressing
- CRC Checksum
- Read/Write Instructions
Specifications
| Supported baud rates | 1200, 2400, 4800, 9600, 19200 bit/s |
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| RS485 communication distance | over 1 km |
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| Maximum devices on RS485 line | 101 meters (60+ need repeater) |
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| Maximum devices without repeater | 32 meters or computers |
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| Write endurance per storage unit | at least 100 000 writes |
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| Data frame format | 1 start bit, 8 data bits, no parity, 1‑2 stop bits |
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| Response time to command | 0‑0.2 seconds |
Frequently asked questions
How many meters can be connected to a single RS485 interface?
Up to 101 meters can share one RS485 interface, but a repeater is recommended when more than 60 devices are connected.
What baud rates are supported by the AI series meter communication interface?
The interface supports baud rates of 1200, 2400, 4800, 9600 and 19200 bit/s.
What is the maximum response time for the meter after a command?
The meter replies within 0 to 0.2 seconds after receiving a command.
How is the CRC checksum calculated for a read command?
For a read command the CRC is calculated as (parameter code × 256) + 182 + ADTR, then the low‑byte and high‑byte of the 16‑bit sum are used.