SSPS4X เครื่องส่งสัญญาณความดัน Pressure Transmitter QDW90A 0-500Bar GO4P3G5 Output RS485 MODBUS RTU

คำอธิบาย

Pressure Transmitter QDW90A DX50A RS485 MODUBUS RTU

• Measuring range -0.1~100MPa Customization
• Compensated temperature -10-70°C
• Ambient temperature -20 – 85°C
• Enclosure protection  IP65
• Pressure type Gauge, absolute, negative pressure
• Zero temperature drift +0.03% FS/°C
• Sensitivity temperature drift +0.03% FS/°C
• Overload pressure 200% FS

Example Ordering Code

Code QDW90A 0-500bar DC24VGO4 P3 G5

QDW90A DC24V Range: 0-500bar G O4 P3 G5 NPT 1/4

• Pressure Transmitter Model QDW90A RS485 MODBUS RTU
• W Range: 0-500bar
• V Power Supply DC24V (DC12 – 36V)
• G Guage
• O4 Output signals RS485
• P3 Accuracy 0.2% FS
• G5 Thread Size NPT 1/4

Thread Size

• G1: M20x1.5
• G2: G 1/2
• G3: G 1/4
• G4: M14x1.5
• G5: NPT 1/4
• G6: PT 1/4
• G7: NPT 1/2
• G8: G 1/4

* NPT เป็นเกลียวมาตรฐานอเมริกา (National Pipe Thread Taper) เกลียวเรียว (Taper) คือขนาดเส้นผ่านศูนย์กลางของเกลียวจะค่อยๆ เล็กลง มักใช้ในงานระบบท่อประปาและแก๊ส

* G เป็นเกลียวมาตรฐานอังกฤษ (British Standard Pipe Parallel – BSPP)  เกลียวตรง (Parallel) คือขนาดเส้นผ่านศูนย์กลางของเกลียวเท่ากันตลอด มักใช้ในงานระบบไฮดรอลิกและนิวเมติก

Electrical connection

• Pin 1 Red : Power Supply DC24V (DC12 – 36V)
• Pin 2 Black : GND
• Pin 3 RS485 A
• Pin 4 RS485 B

Output signals O4 RS485

Dimension

**MODBUS Pressure Transmitter Communication Protocol**

1.1 Overview:
This protocol adheres to MODBUS communication standards and employs a sub-centralized
RTU mode within the MODBUS framework using RS485 half-duplex operation.

1.2 Serial Data Format:
Serial Port Settings: no parity check, 8 data bits, 1 stop bit.
Example: 9600,N,8,1 Meaning: 9600 BPS with no parity check; 8 data bits; and 1 stop bit.
The supported serial port baud rates for this transmitter are as follows:
00 1200240 0480 0960 0192
CRC Check Polynomial: 0xA001.

All data during communication is processed in accordance with double-byte formatted data
structures. If dealing with floating-point numbers during writing operations, it is essential to
read decimal points to ascertain data size.

1.3. Communication Format:

1. Review the command structure (03 Function Code)

A. Structure of the transmitted read command:

B. Return read data format: example

2. Write command format (06 function code)

A. Structure of the transmitted read command:

B. Return read data format: example

3. The abnormal response is returned

4. Supported commands and meaning of commands and data: The MODBUS-RTU command list is as follows:

Function Code

1. **Revised Instructions:**
1. When the baud rate is modified, the transmitter will respond with the updated data reflecting the baud rate specified
by the host. Following this response, the transmitter’s baud rate will adjust to the new target value.

2. Upon modifying the address, data will be returned to its pre-modification state, and subsequently, the transmitter’s
address will automatically update after sending a reply.

3. Executing a save and reply factory command will return original values, indicating that the transmitter has
successfully acknowledged commands from the host.

4. It is important to note that when restoring factory settings, parameters saved at factory defaults may differ from
those stored by users; thus, discrepancies in address, baud rate, and calibration data may occur. Therefore, it is necessary
to re-scan for transmitters after restoring factory parameters.

5. Users are permitted to modify only three specific pieces of information: address (noted twice), baud rate, and zero offset value.

6. General users are prohibited from altering calibration data within the transmitter; if calibration adjustments are
required, please contact our company for specialized calibration software. Attempting to send commands for modifying
calibration data without authorization may result in abnormal command codes being outputted by the transmitter. For
any modifications related to calibration data, please utilize our designated calibration software.

7. If readout data includes floating-point numbers (e.g., 6.000), this protocol specifies communication through shaped
data representation; therefore, what is read as “6000” should be processed according to decimal placement—if indicated
as three decimal places (i.e., position of decimal point = 3), then compute as follows: \(6000 /10^3\) which results in \(6.000\).