HL-SO series outdoor temperature and humidity sensor

The HL-SO Series Outdoor Temperature and Humidity Sensor is designed for reliable outdoor and environmental monitoring in HVAC, building automation, energy management, and other temperature and humidity measurement applications.

The series provides multiple sensing and signal output options, including NTC10K, NTC20K, PT1000, 0–10V, and 4–20mA, allowing users to select the appropriate configuration for different controllers and building automation systems.

Selected models combine temperature and relative humidity measurement in one device, while different output configurations support flexible integration with HVAC controllers, DDC systems, monitoring platforms, and other automation equipment.

With a wide operating environment and IP65 protective level, the HL-SO Series is suitable for applications where sensors need to operate reliably in outdoor or demanding environmental conditions.

Outdoor Temperature and Humidity Monitoring

Temperature and relative humidity are important environmental parameters for HVAC control, building automation, energy management, and equipment protection.

The HL-SO Series provides different combinations of temperature and humidity sensing to meet various application requirements. Depending on the model, the sensor can provide:

• Temperature measurement only
• Temperature and relative humidity measurement
• Passive temperature signals such as NTC10K, NTC20K, and PT1000
• Analog temperature outputs such as 0–10V and 4–20mA
• Analog relative humidity outputs
• Combined temperature and humidity outputs

This flexible model structure allows the sensor to be matched with different controllers and signal acquisition systems.

Relative Humidity Measurement

Selected HL-SO Series models combine temperature and relative humidity sensing in the same housing.

The humidity measurement range can cover 0–100% RH depending on the selected model, while humidity accuracy varies according to the specific configuration.

The sensor can therefore provide environmental information required for:

• HVAC monitoring
• Indoor and outdoor climate monitoring
• Building automation
• Air-conditioning control
• Humidity management
• Equipment environment monitoring
• Energy management systems

Professional temperature and humidity sensors commonly combine temperature and relative humidity measurement in a single device. R. M. Young, for example, offers combined probes using a humidity sensing element together with a precision temperature sensor, with analog output options including 0–1 VDC and 4–20mA.

Multiple Analog Signal Outputs

A major feature of the HL-SO Series is its range of signal output configurations.

This allows the sensor to integrate with different types of HVAC controllers and building automation equipment.

For example, a 4–20mA output can be connected to a controller with a current input, while a 0–10V output can be connected to a compatible analog voltage input.

The same principle is widely used across professional environmental sensors. R. M. Young provides temperature and humidity probes with both voltage and current output configurations, while Setra's humidity sensors also offer 4–20mA and 0–10V output options.

IP65 Protection for Outdoor Applications

The HL-SO Series features an IP65 protective level, making it suitable for applications where the sensor may be exposed to dust and water spray.

The outdoor sensor design is intended for environmental monitoring applications where reliable measurement is required under changing temperature and humidity conditions.

When installing an outdoor temperature and humidity sensor, the installation position should be selected carefully to avoid direct heat sources and conditions that may affect measurement accuracy.

For professional outdoor environmental measurement, sensor protection from solar radiation and precipitation is also an important consideration. R. M. Young uses dedicated multi-plate and aspirated radiation shields to reduce measurement errors caused by solar radiation and precipitation.

For the HL-SO Series, the final installation method should follow the product's installation requirements and the actual project environment.

Wide Operating Environment

The HL-SO Series is designed to operate across a wide environmental range:

• Working temperature: -40–80°C
• Working humidity: 5–95% RH
• Humidity condition: No condensation
• Protection level: IP65

This operating range allows the series to be used in a variety of outdoor and environmental monitoring applications.

HVAC and Building Automation Integration

Outdoor temperature and humidity information can be used as input data for HVAC and building automation systems.

A typical building automation architecture may include:

Outdoor Sensor → DDC Controller → HVAC Equipment → Building Management System

The HL-SO Series can provide outdoor environmental data to compatible controllers, which can then use the measured values for HVAC control, monitoring, scheduling, or energy management.

HaiLin Controls provides a broader HVAC automation portfolio covering thermostats, sensors, DDC controllers, gateways, valves, and building management platforms, allowing environmental sensors to be integrated into complete building automation solutions.

Applications

Building Automation

The HL-SO Series can provide outdoor temperature and humidity data for building automation systems.

The measured values can be used by controllers and management platforms to monitor environmental conditions and support HVAC operation.

HVAC Systems

Outdoor temperature is an important parameter in many HVAC control strategies. Humidity information can also support environmental monitoring and air-conditioning management.

The HL-SO Series can be connected to compatible HVAC controllers through NTC, RTD, 0–10V, or 4–20mA signals depending on the selected model.

Commercial Buildings

The sensor can be used in office buildings, commercial complexes, hotels, and other facilities where environmental conditions need to be monitored as part of HVAC or building management.

Industrial Facilities

Models with analog outputs such as 4–20mA can be used in industrial monitoring and control environments where standardized signal transmission is required.

Energy Management

Outdoor environmental information can be incorporated into HVAC energy management strategies. Controllers can use temperature and humidity data together with other building parameters to optimize system operation.

Environmental Monitoring

The combination of temperature and relative humidity measurement makes selected models suitable for general environmental monitoring applications.

Suitable for Different Control Architectures

The HL-SO Series can support different system architectures because of its multiple output configurations.

Passive Sensor Integration

Models using NTC10K, NTC20K, or PT1000 can be connected directly to compatible controllers designed for resistance-based temperature sensing.

Analog Voltage Integration

Models with 0–10V outputs can transmit temperature or humidity information to compatible analog inputs.

Analog Current Integration

Models with 4–20mA outputs can integrate with controllers and monitoring equipment using current-loop inputs.

This flexibility helps reduce the need for different sensor platforms across projects with different controller interfaces.