High Temperature Humidity Transmitter Around 200℃ RS485 Modbus 4-20mA Output

Product Detail

HG808 Super High Temperature Humidity Transmitter

The HG808 is an industrial-grade temperature, humidity, and dew point transmitter designed for harsh environments with high temperatures. In addition to measuring and transmitting temperature and humidity, the HG808 calculates and transmits the dew point, which is the temperature at which air becomes saturated with water vapor and condensation begins to form.

Here’s a breakdown of the key features:

Temperature range: -40 ℃ to 200 ℃ (-40 °F to 374 °F)
Probe: The transmitter is equipped with a high-temperature probe that is waterproof and resistant to fine dust.
Output: The HG808 offers flexible output options for temperature, humidity, and dew point data:Display: The transmitter has an integrated display for viewing temperature, humidity, and dew point readings.
- Standard industrial interface RS485 digital signal
- 4-20 mA analog output
- Optional: 0-5v or 0-10v output
Connectivity: The HG808 can be connected to various industrial control systems, including:
- On-site digital display meters
- PLCs (Programmable Logic Controllers)
- Frequency converters
- Industrial control hosts

Product Highlights:

▪Integrated design, simple and elegant
▪Industrial grade ESD safety protection and power supply anti reverse connection design
▪Using waterproof, dustproof, and high-temperature resistant probes
▪Sensitive waterproof and anti fine dust high-temperature probe
▪Standard RS485 Modbus RTU communication protocol

The ability to measure dew point makes the HG808 ideal for applications where moisture control is critical, such as:

HVAC systems
Industrial drying processes
Weather monitoring stations

By measuring and transmitting all three values (temperature, humidity, and dew point), the

HG808 provides a comprehensive picture of moisture conditions in harsh environments.

HG808 Data Sheet Details

HG808-T

Parameter	Value
Temperature range	-40 ~ 200°C （ U-series） / -50 ~ 150°C （ W-series）/ -40 ~ 150°C （ S-series）
Dew point range	-60 ~ 80°C (U series ) / -60 ~ 80°C ( W-series ) / -80 ~ 80°C ( S-series )
Humidity range	0 ~ 100%RH (recommended <95%RH)
Temperature accuracy	±0.1°C (@20°C)
Humidity accuracy	±2%RH (@20°C, 10~90%RH)
Dew point accuracy	±2°C (± 3.6 °F) Td
Input and output	RS485 + 4-20mA / RS485 + 0-5v / RS485 + 0-10v
Power supply	DC 10V ~ 30V
Power consumption	<0.5W
Analog signal output	Humidity + Temperature / Dew point + Temperature (choose one of the two)
	4~20mA / 0-5V / 0-10V (choose one)
RS485 digital output	Temperature, humidity, dew point (read simultaneously)
	Resolution: 0.01°C / 0.1°C optional
Communication baud rate	1200、2400、4800、9600、19200、115200 can be set, default 9600 bps
Acquisition frequency	Fastest 1s response, others can be set according to PLC
HG808 Dew Point Transmitter User Manual V1.1	9
Byte format	8 data bits, 1 stop bit, no parity
Pressure resistance	16 bar
Operating temperature	– 20℃ ~ +60℃, 0%RH ~ 95%RH (non-condensing)

various features of the HG808 Series. Please check below. :

Model	Temperature Range (°C)	Humidity Range (% RH)	Dew Point Range (°C)	Accuracy (Temperature/Humidity/Dew Point)	Special Features	Applications
HG808-T Series ( High Temperature Transmitter )	-40 to +200℃	0-100%RH	N/A	±0.1°C / ±2%RH	Ultra-high temperature resistant sensing element, 316L stainless steel probe. Maintains good humidity collection performance even at high temperatures between 100°C and 200°C.	Collecting humidity data from high-temperature gases in various applications like furnace kilns, high-temperature ovens, and coking gas pipelines.
HG808-H Series ( High Humidity Transmitter )	-40 to +190℃	0-100%RH	N/A	±0.1°C / ±2%RH	Features high wet humidity sensing with excellent corrosion resistance. Employs a robust cast aluminum housing and a stainless steel sensor assembly for durability. Maximum humidity range extends up to 98% RH.	Suitable for use in industrial environments with high humidity levels, particularly in applications with relative humidity ranging from 90% to 100%.
HG808-C Series ( Precision Transmitter)	-40 to +150℃	0-100%RH	N/A	±0.1°C /± 1.5%RH	Provides long-term stable and high-accuracy measurement performance across a wide measurement range (0-100% RH, -40°C to +150°C). Employs high-quality sensors and advanced calibration technology for sustained precision.	Ideal for use in various fields requiring precise measurements, including biopharmaceuticals, precision machinery processing, laboratory research, food processing, and storage.
HG808-K Series (Harsh Environment Transmitter )	-40 to +190℃	0-100%RH	N/A	±0.1°C / ±2%RH	Combines a high-precision ultra-high temperature resistant sensing element with a 316L stainless steel probe. Features a probe heating function for removing condensation, sensor anti-interference, and is designed for long-term stability.	Suitable for harsh industrial environments with high/low temperatures, high humidity, dry conditions, oil and gas, dust, particle pollution, and exposure to corrosive substances.
HG808-A Series (Ultra High Temp Dew Point Meter)	-40 to +190℃	N/A	-50 to +90℃	±3°C Td	Designed specifically for measuring dew point in high-temperature and dry environments. Features a robust cast aluminum housing and stainless steel sensor assembly for accurate measurements at temperatures up to 190°C.	Ideal for dew point measurement in challenging 190℃ high-temperature and dry environments.
HG808-D Series (Inline Dew Point Meter)	-50 to +150℃	N/A	-60 to +90℃	±2°C Td	Utilizes a high-quality moisture-sensitive element and advanced calibration techniques to deliver accurate dew point transmitter. Offers consistent ±2°C dew point accuracy within a dew point range of -60°C to +90°C.	Suitable for industrial, non-harsh environments where precise humidity control is crucial. Applicable in areas like lithium battery production, semiconductor applications, and glove boxes for microscopic water detection.
HG808-S Series ( Inline Dew Point Meter )	-40 to +150℃	N/A	-80 to +20℃	±2°C Td	Designed to operate in extremely dry environments and measure moisture in gases. Features a dew point range extending down to -40°C, making it suitable for applications requiring strict humidity control.	Measures low dew point values in industrial settings demanding precise humidity management.

Applications for Extreme Environments

Industrial processes often involve extreme temperatures and humidity levels. Regular transmitters can’t handle these harsh conditions. Here’s a breakdown of applications where high-temperature and humidity transmitters (operating over 200°C and down to -50°C) are crucial:

High-Temperature Applications (Over 200°C):

Industrial Ovens and Furnaces: Monitoring temperature and humidity is vital in curing processes like painting, drying ceramics, and heat treating metals. Precise control ensures product quality and prevents defects.
Power Generation: Humidity measurement in power plants helps prevent corrosion in turbines and other equipment exposed to high temperatures and steam.
Chemical Processing: Accurate temperature and humidity data is essential for safe and efficient chemical reactions in reactors, dryers, and pipelines. Deviations can lead to hazardous situations or product contamination.
Semiconductor Manufacturing: Creating microchips involves tightly controlled environments with high temperatures and low humidity. Transmitters ensure proper conditions for sensitive processes like photolithography and etching.
Glass Manufacturing: Glass production requires precise temperature and humidity control during melting, blowing, and annealing. Transmitters help maintain consistent glass quality and prevent defects.

Low-Temperature Applications (Down to -50°C):

Cold Storage Facilities: Monitoring temperature and humidity in freezers and cold warehouses helps maintain optimal conditions for food preservation and prevent spoilage.
Cryogenic Applications: Extremely low temperatures are used in research and industrial processes like superconductivity and liquefied natural gas (LNG) storage. Transmitters ensure safe handling and prevent equipment damage from ice formation.
Climate Monitoring: These transmitters are valuable tools for weather stations in extreme cold environments like the Arctic or high mountain regions. They provide accurate data for climate research and weather forecasting.
Aerospace Industry: Testing aircraft components for functionality in frigid conditions requires precise temperature and humidity control. Transmitters simulate real-world scenarios and ensure aircraft safety.
Wind Turbine Icing: Detecting and measuring ice formation on wind turbine blades is crucial for safe operation. Transmitters help prevent blade damage and power generation loss in cold climates.