Temperature-Humidity Transmitter
Polwax RHT400 DM
Part Code. 0397
- Without Display
- Modbus RTU RS485
- Duct mounted
- Excellent linearity
- Wide sensing range
- Good long term stability
A high-precision, high-temperature monitoring tool for crucial applications needing precise environmental management is the Polwax RHT400 DM Temperature & Humidity Transmitter. This transmitter is designed to satisfy the requirements of industrial, HVAC, and specialty applications with a broad operating temperature range of -40°C to 125°C and humidity measurement up to 100% RH. It is perfect for high-temperature procedures and demanding industrial applications because of its sturdy 300 mm stainless steel sensor with an SS filter, which guarantees performance and endurance in harsh environments.
Product Overview
The Polwax RHT400 DM Series is a duct-mount temperature and humidity transmitter engineered for precise environmental monitoring and control in industrial, commercial, and HVAC applications. This series combines robust sensor technology with reliable performance to deliver accurate real-time measurement of both temperature and relative humidity, ensuring optimal climate conditions for sensitive processes and controlled environments.
Designed for duct installation, the RHT400 DM series is ideal for applications such as air handling units (AHUs), clean rooms, pharmaceutical facilities, warehouses, manufacturing zones, and other environments where dependable environmental data is critical for process control and energy efficiency.
The series includes multiple variants tailored to specific requirements:
- RHT400 DM – Standard transmitter for general temperature and humidity monitoring.
- RHT400 DM (HT) – High-temperature variant suitable for environments with elevated temperature conditions.
- RHT400 DM (HT+HA) – High-temperature model with enhanced accuracy for critical applications demanding exceptional precision.
All models support versatile output options such as 4–20 mA, RS485 MODBUS RTU, and optional 0–10 V, allowing seamless integration with building automation and industrial control systems. The transmitters are built with a durable enclosure and stainless-steel sensing elements to withstand challenging conditions while maintaining long-term stability and reliability.
Polwax RHT400 DM is a high-precision duct-mount temperature & humidity transmitter designed for accurate environmental monitoring in industrial and HVAC applications. It delivers reliable real-time measurement of temperature and relative humidity for efficient climate control and process stability.
Polwax RHT400 DM – Standard configuration that offers dependable performance across a wide range of environments, ensuring accurate measurement for general industrial, commercial, and HVAC systems.
Polwax RHT400 DM (HT) – High-Temperature variant engineered for use in elevated temperature environments while maintaining precise humidity monitoring. It’s suitable for more demanding industrial processes and high-heat applications.
Polwax RHT400 DM (HT+HA) – Advanced model combining High-Temperature (HT) capability with High-Accuracy (HA) sensing. This variant delivers exceptional precision for critical applications requiring both extended temperature range and superior measurement accuracy.
Applications
Agriculture & Greenhouses
Ensure optimal crop growth and plant health with the Polwax RHT400 DM Series. This duct-mounted temperature and humidity transmitter delivers precise real-time environmental data, helping you maintain the ideal climate inside greenhouses and agricultural facilities.
Pharmaceutical
Maintain strict environmental control in pharmaceutical production and storage with the Polwax RHT400 DM Series. This high-precision duct-mount temperature and humidity transmitter provides reliable, real-time monitoring to help ensure compliance with regulatory standards.
Storage & Warehouse
Ensure stable environmental conditions in storage and warehouse facilities with the Polwax RHT400 DM Series. Its accurate temperature and humidity monitoring helps protect inventory, reduce spoilage, and maintain quality control by enabling efficient climate regulation throughout large spaces.
Food & Beverage
Maintain stringent climate control in food and beverage environments with the Polwax RHT400 DM Series. Its precise temperature and humidity measurement ensures product quality, extends shelf life, and supports safe storage and processing by enabling accurate environmental monitoring and control.
HVAC
Optimize HVAC system performance with the Polwax RHT400 DM Series. Its accurate temperature and humidity sensing enables efficient airflow control, improved comfort, and energy savings by providing reliable real-time environmental data for duct-mounted monitoring and automation systems.
Clean Rooms
Ensure precise climate control in clean room environments with the Polwax RHT400 DM Series. Its high-accuracy temperature and humidity monitoring supports strict contamination control, regulatory compliance, and stable conditions essential for critical processes in biotech, pharma, and high-tech manufacturing.
Technical Data
| Media Compatibility | Air, non-combustible, non-corrosive gases |
| Model No |
RHT400 DM / RHT400 DM (HT) / RHT400 DM (HT+HA) |
| Part Code |
0397 4030 (RHT400 DM) / 0397 4031 (RHT400 DM) / 0397 4032 (RHT400 DM – HT) / 0397 4033 (RHT400 DM – HT+HA) |
| Measuring Range |
RHT400 DM → T: -40 to 85°C & RH: 0–100% / RHT400 DM → T: 0 to 100°C & RH: 0–100% / RHT400 DM (HT) → T: -40 to 125°C & RH: 0–100% / RHT400 DM (HT+HA) → T: -40 to 125°C & RH: 0–100% |
| Accuracy |
Standard Models → T: ±0.4°C & RH: ±1.8% / HT+HA Model → T: ±0.1°C & RH: ±0.8% |
| Display | Without Display |
| Inputs | Temperature & Humidity |
| SS Probe Length | 400 mm |
| Dimensions | 75 × 35 × 75 mm |
| Protection Class | IP54 |
| Mounting | Duct Mount |
| Language | English |
| Supply Voltage | 24V DC |
| Output | 4–20mA, RS485 MODBUS RTU / 0–10V (Optional) |
| Scope of Supply | Calibration Certificate, GUI Software, SS Adaptor, Instruction Manual |
Temperature & Humidity Transmitter – RHT400 DM Series
The Polwax RHT400 DM series duct-mount temperature and humidity transmitters are designed for high-accuracy environmental monitoring in HVAC ducts, clean rooms, pharmaceutical facilities, food processing units, warehouses, and industrial applications. These transmitters provide stable, real-time temperature and humidity data to ensure efficient climate control and process reliability.
Model Variants
RHT400 DM – Standard Model
RHT400 DM (HT) – High Temperature
RHT400 DM (HT+HA) – High Temp & High Accuracy
Duct Mount Design
Stainless steel probe with duct mounting for accurate air-stream measurement.
High Accuracy Monitoring
Reliable sensing of temperature and humidity for critical controlled environments.
High Temperature Support
HT models are suitable for elevated temperature applications without loss of accuracy.
Industrial Output Options
Supports 4–20mA, RS485 Modbus RTU and optional 0–10V outputs.
Wide Application Use
Ideal for HVAC systems, clean rooms, pharma, food processing & warehouses.
Robust Protection
IP54-rated enclosure ensures reliable operation in industrial environments.
24V DC Supply
Designed for continuous operation with standard 24V DC power supply.
