RS485 and 4-20mA temperature and humidity transmitter PC Replacement Probe

Item Number:  HG803-7W4P-02

The HG803 Interchangeable Probe Transmitter is paired
with a cost-effective detachable and replaceable
probe. The detachable probe design allows for independent
disassembly and replacement of the probe module
and transmitter module.

RS485 and 4-20mA both Output

Product Highlights:

1.Integrated split structure design, lightweight and convenient.
2.Easy to replace and r educe equipment maintenance costs
3.High cost-effectiveness, reliable and affordable
4.Suitable for sensor vulnerable temperature and humidity
measurement scenarios, such as smart farming, smart
agriculture, etc

SPECIFICATION

* Temperature Range: -40~100°℃(Plastic lnterchangeable probe)
* Temperature Accuracy: 土0.3°℃(25°C) ,(Higher precision is customizable)Humidity Range: 0~100% RH
* Humidity Accuracy: 士3%RH(60%RH, 25°C)(Higher precision is customizable) 

* Long-term Temperature Stability: ≤0.1°C/y

* Long-term Humidity stability: ≤1%RH/y
* signal output : 4-20 mA temperature and humidity two analog capacity + RS485 signal output
* Baud rate: 1200、2400、4800、9600、19200、115200 can set, default is 9,600 pbs
* Transmitter Circuit operating Temperature: -20°℃~+60°℃, 0%RH~95%RH,Non-knot dew supports both single-register and multiple-register reads
* Industrial grade ESD safety protection and power supply reverse protection design supports both single-register and multiple-register reads
* Digital output can set the output of 0.1 or 0.01 resolution

HG803 Data Sheet Details

Technical DataDescription
DC power supply10 ~ 30V DC (12V recommended)
Maximum power consumptionAbout 1.2W
Current outputAbout 1.2W
Voltage outputAbout 1.2W
Typical accuracy (Temperature)±0.3℃ (25℃) / ±0.54℉ (77℉)
Typical accuracy (Humidity)±3%RH (60%RH, 25℃)
Measuring mediumAir
Measuring range (Temperature)-40℃ ~ 80℃ / -40℉ ~ 176℉ (default)
Measuring range (Humidity)0%RH – 100%RH
Long-term stability (Temperature)≤ 0.1℃ /y
Long-term stability (Humidity)≤ 1%RH /y
Response time (Humidity)≤ 8s (1m/s Wind speed)
Response time (Temperature)≤ 15s (1m/s Wind speed)
Analog outputSignal Current 4 – 20 mA
Digital outputRS485 Communication (Modbus) protocol
Data bit length8 bits
Parity check modeNone
Stop bit length1 bit
Default Modbus communication address1
Function code03
Baud rate1200, 2400, 4800, 9600, 19200, 115200 (optional, default 9600 bps)
Load capacity (Current output)≤ 600Ω
Load capacity (Voltage output)≤ 250Ω
Transmitter circuit operating temperature-20℃ ~ +60℃, 0%RH ~ 95%RH (non-condensation)

About Installation

HG803 Wire Connect Installation diagram

Wiring Standard of 4-20mA + RS485 Analog Output Type

Line ColorDefinitionSpecification
Power Cord  
RedPower supply positive10 ~ 30V DC
BlackPower supply negativeGND
Analog Output Lines  
BrownTemperature signal positive4-20mA output
BlueTemperature signal negativeConnects to Black (GND)
GreyHumidity signal positive4-20mA output
WhiteHumidity signal negativeConnects to Black (GND)
RS485 Wiring  
YellowRS485ATwisted pair cable
GreenRS485BTwisted pair cable

Additional Notes:

  • Load Capacity:
    • Current output: ≤ 600Ω
    • Voltage output (not applicable in this table): ≤ 250Ω
  • Applicable Models: HG803-1W4P, HG803-2W4P, HG803-3W4P, HG803-4W4P, HG803-5C4P, HG803-6C4P, HG803-7W4P, HG803-8W4P
 

Important:

  • Refer to the device manual for specific connection instructions and any additional requirements.
  • Ensure proper termination resistors are used on the RS485 bus as per the device manual and relevant communication standards.
  • Do not attempt electrical wiring without proper knowledge and qualifications.
  •  

APPLICATION

These transmitters can be used for indoor air temperature and humidity monitoring in various industrial plant, clean room, lab, machine room, commercial buildings, airport, and schools. 

The modbus interface is documented and integrator friendly. They also have transducer outputs for connecting as analog inputs to all popular control systems. 

Various models are available:

Duct Mount,

Wall Mount,Room Mount and 2 meter cable.BACnet MS/TP and 

Modbus RTU protocols over RS485,with an ethernet port.

Download Product Manual / Certification / Software

2. Check All Other Download Files

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