Contents
- 1 Hardware parameters
- 2 Terminal Wiring Diagram
- 2.1 HJ2009A terminal diagram
- 2.2 HJ2009B terminal diagram
- 2.3 HJ2009C terminal diagram
- 2.4 HJ2009D terminal diagram
- 2.5 HJ2009H terminal diagram
- 2.6 HJ2009K terminal diagram
- 2.7 HJ2009P terminal diagram
- 2.8 HJ2009K16 terminal diagram
- 2.9 HJ2009P16 terminal diagram
- 2.10 HJ2009Q terminal diagram
- 2.11 HJ2009S terminal diagram
- 3 Wiring diagram
HJ2000 Series Hardware Manual V1.1
Hardware parameters
RS485 Parameters
Port | 1 |
Baud rate | 400K |
Data bits | 8 Bits |
Stop bit | 1 Bits |
Check | None |
Buffer | 4MBytes |
Interface | Terminal(LTX-LRX) |
Digital input
Number of channels | Determined by model |
Input type | Optical isolation PNP/NPN |
Rated voltage | 24V |
Access method | Single line |
Response time | 1 ms |
Protect | Overcurrent and overvoltage |
Digital output
Number of channels | Determined by model |
Output type | PMOS tube output |
Rated voltage | 25V |
Output Current | 0.5A |
Response time | 1 ms |
Protect | Overcurrent and overvoltage |
Analog input
Number of channels | Determined by model |
Input type | 0~20mA/0~5V/0~10V(Optional) |
Precision | 0.1% |
Sampling time | 1 ms |
Input resistance | 50R(current)/1M ohm(voltage) |
Protect | Overcurrent |
Analog output
Number of channels | Determined by model |
Output type | 0~20mA/0~5V/0~10V(Optional) |
Precision | 0.1% |
Sampling time | 1 ms |
Output impedance | 50R(current)/100R(voltage) |
Protect | Overcurrent |
Address encoding
Address bits | 6 |
Address sequence | 1、2、3、4、5、6 |
Terminal Wiring Diagram
HJ2009A terminal diagram

HJ2009B terminal diagram

HJ2009C terminal diagram

HJ2009D terminal diagram

HJ2009H terminal diagram

HJ2009K terminal diagram

HJ2009P terminal diagram

HJ2009K16 terminal diagram

HJ2009P16 terminal diagram

HJ2009Q terminal diagram

HJ2009S terminal diagram

Wiring diagram
Hardware connection of IO expansion module
LTX/LRX are respectively connected to the LTX/LRX terminals of HJ52XX series devices

K-type thermocouple wiring
PT1000 is used for cold junction temperature measurement, so the PT1000 sensor must be connected to the terminal block of the K-type thermocouple, as close as possible to the connection point of the K-type thermocouple to reduce the cold junction temperature measurement error.

Thermocouple temperature measurement principle

K- and K+ represent two different metal materials. The A and B terminals are the connection points of these two metal materials and copper and other metal materials. They are located in the normal temperature environment, called the cold terminal, and the C point is the measurement point.
Due to the thermoelectric effect, if there is a temperature difference between points A and C, there will be a voltage difference between points A and C. Similarly, if there is a temperature difference between points B and C, there will be a voltage difference between points B and C. A voltage difference is generated. Because K+ and K- are two different metal materials, the voltage difference between A and C is not the same as the voltage difference between B and C. Point C is the welding point of K+ and K- two metal materials, point C The electric potential is the same, then a voltage difference is formed between A and B, which is the basic principle of thermocouple temperature measurement.
If you want to accurately measure the temperature t1 at point C, you must accurately measure the temperature t0 between points A and B, and t0 is the cold junction temperature.
HJ5209K series equipment uses high-precision PT1000 platinum resistance to measure the temperature t0 between points A and B.
Thermal resistance wiring method

- The above figure is a three-wire wiring method. If it is a two-wire thermal resistance, directly short A/B, and then connect to one end of the thermal resistance.
- The three-wire thermal resistance can completely eliminate the measurement error caused by the line length. It is recommended to use the three-wire thermal resistance wiring method as much as possible.
- 1A/1B are connected to the same end of the thermal resistance, the other end of the thermal resistance is connected to GND, and each two measurement channels share a GND, as shown in the figure above.
Analog input wiring method
GND, AI0.0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, GND form a group of 8-channel analog input.
Note: the wiring method of the 2-wire current sensor, the power supply of the sensor is connected to 24V, and the power supply of the sensor is connected to the AI point. For three-wire and four-wire sensors, 24V power supply is required for the sensor. The positive signal of the sensor signal output terminal is connected to AI point, and the negative terminal of the signal is connected to GND. The three-wire sensor has no negative signal terminal, so it is not necessary to connect. The connection method of the voltage sensor is the same as that of the four-wire current connection.

Analog output wiring method
Note: Two-wire output wiring, AQ point is connected to P+ of the input device, and P- of the input device is connected to 0V.
