Mod X420 Flow Module
Communication Protocol
Summary: Mod X420 supports the RS485 Modbus RTU communication, it can also transform the pulse signal to flow rate then to 4-20mA output.
Model: Mod X420
Working Voltage: DC24V
Introduction
This series of products follows the MODBUS protocol instructions. Available command codes are 0x03, 0x06, and 0x10. CRC check: low bit first, high bit last.
Example: Use the 03 instruction to read multiple registers
0x010 x030 x000 x000 x000 x030 x050 xCB
(Continuously read the values of 3 registers from the 0x0000 register of device No. 0x0001)
To write to a single register use the 06 instruction
0x01 0x06 0x00 0x01 0x00 0x03 0x19 0xCA
(Write 0x0003 to the 0x0001 register of device No. 0x0001)
Writing to multiple registers uses 10 instructions
0x010 x100 x000 x000 x000 x020 x040 x000 x000 x000 x010 x320 x6F
(Write 0x0000 to the 0x0000 register of device No. 0x0001, and write 0x0001 to the 0x0001 register of device No. 0x0001)
Default Settings:
Baud rate: 9600 (decimal)
MODBUS device address: 1 (decimal)
Flowmeter constant K value: 500 (decimal)
To modify baud rate parameters
The default baud rate is 9600, and the reading is 2.
If you modify the baud rate, modify the parameters as follows. (If you enter a value other than the value in the table, the baud rate will be restored to 9600, but when reading, it will be displayed as the modified value is not 2)
Setting | Baud Rate |
0 | 2400 |
1 | 4800 |
2 | 9600 |
3 | 19200 |
4 | 115200 |
Register Address | Register Function |
---|---|
0x0000 | Baud Rate |
0x0001 | Device Address, can be modified to 0x0001-0x00F7 (decimal 1-247) |
0x0002 | Decimal(Default 2: 2 decimals of flow rate) |
0x0003 | Flow sensor pulse K value, the value read and written is 100 times the actual value (maximum 65535) |
0x0004 | Permanent cumulative flow high register, unit, L (maximum 65535) |
0x0005 | Permanent cumulative flow low register, unit, L (maximum 65535) |
0x0006 | Permanent cumulative flow decimal, the reading is 100 times the actual value, unit, L |
0x0007 | Permanent accumulated flow pulse value(related with 0x0006)(accumulate 1L and return to 0) |
0x0008 | Default:10K Resistance of temperature sensor(invalid) |
0x0009 | Lower limit of the flow range(invalid) |
0x000A | Upper limit of the flow range(invalid) |
0x000B | Coefficient A of pressure sensor(invalid) |
0x000C | Coefficient B of pressure sensor(invalid) |
0x000D | Temporary accumulated flow high register, unit, L (maximum 65535) |
0x000E | Temporary accumulated flow low register, unit, L (maximum 65535) |
0x000F | Temporary cumulative flow decimal, the reading is 100 times the actual value, unit, L |
0x0010 | Temporary accumulated flow pulse value(related with 0x000C) (accumulate 1L and return to 0) |
0x0011 | Real-time flow rate, unit: L/min, the reading is 100 times the actual value |
0x0012 | Real-time pulse number unit Hz, the reading is 100 times the actual value |
0x0013 | Temperature reading Unit: ℃ (invalid) the reading is 100 times the actual value |
0x0014 | Pressure reading Unit Kpa (invalid) |
Note:
1. After the address, baud rate, K factor, and permanent cumulative flow are modified, the device needs to be restarted to take effect.
2. Please close the input pipeline before clearing the cumulative flow to prevent water from passing by again after clearing. The value changes after 60 seconds, and the program changes the value again so that the cumulative amount cannot be returned to zero.
3. Reset the temporary cumulative flow after power failure, and record the permanent cumulative flow every 60 seconds. (Flows must exceed 1 litre within 60 seconds to be recorded)
4. When the low bit of the register is full of 65535, it will enter 1 into the higher bit. Example: Assuming a flow sensor with a cumulative flow higher register is 1 and the cumulative flow lower register is 2; then the total flow is 65535 * 1 +2 = 65537L
5. The maximum storage value of each register is 65,535, and the maximum storage data of the permanent cumulative flow of each flow sensor is 65,535 * 65,535 +65,535 = 4,294,917,600 liters of water
6. During the reset operation, the registers for the permanent accumulated traffic need to be reset at the same time, that is, the registers 3/4/5/6 should be reset at the same time. Temporary cumulative traffic reset is also subject to this rule.
Wiring instructions:
Upper Vcc: Input power positive
Upper GND: Negative input power supply
Top end B, A connects to B, A of 485
Upper AO+ AO- is output4-20mA
Lower Vout: Output power supply positive (red line to water flow sensor)
Lower GND: output power supply negative (connected to water flow sensor black line)
Lower IN01: Signal input (yellow line of water flow sensor)
Lower NTC+ NTC- PS01 (Invalid)
Lower IN02:(Invalid)
Formula:
V=Current Flow Rate, Unit is L/Min
Vmax is the high limit of the flow range, Unit is L/Min
Vmin is the lower limit of the flow range,Unit is L/Min
I=output current unit is mA