A54-21 PM2.5 Sensor

MAXMAC A54-21 is a compact PM2.5 sensor designed for HVAC systems, ventilation systems and indoor air quality monitoring. It provides reliable particulate matter data for air handling units, fresh air control and indoor environmental management systems.

Featuring laser scattering PM2.5 detection and RS485 communication, A54-21 supports easy integration with HVAC controllers, BMS building automation systems and environmental monitoring platforms.

Dedicated PM2.5 particulate monitoring
PM2.5 measuring range: 0-999 µg/m³, resolution 1 µg/m³
Laser scattering particle detection technology
RS485 communication for HVAC, fresh air and BMS system integration
Compact flame-retardant PC+ABS housing for long-term HVAC equipment integration

Sensor Technology Principle

All-in-One Sensor Principle Diagram

Technical Specifications

A54-21 PM2.5 Sensor

Product Name

A54-21 PM2.5 Sensor

Model

A5421

Functions

PM2.5

Communication

RS485

Dimensions

66.4 × 51.4 × 19 mm

Housing Material

PC+ABS, V0 flame-retardant

Operating Voltage

DC12-DC24V

Operating Current

Average: 35 ± 5 mA @ 12.0 VDC; Peak: <150 mA (10 ms), at room temperature

Standby Power Consumption

≤ 1 W

Power Consumption

≤ 3 W

PM2.5 Sensing Principle

Laser scattering technology

PM2.5 Measuring Range

0-999 µg/m³

PM2.5 Resolution

1 µg/m³

PM2.5 Accuracy

≤100 µg/m³: ±15 µg/m³; >100 µg/m³: ±15%

Interface

4-pin socket

Communication Interface

RS485 protocol, 4-pin (+ / A+ / B- / GND)

Physical Connector

GH1.25-4P locking connector

Operating Environment

-10°C to 50°C, 0-95%RH, non-condensing

Storage Environment

-20°C to 65°C, 0-99%RH, non-condensing

The matching GH1.25-4P locking terminal cable should be prepared by the user for connection.

Applicable Systems

HVAC Systems
Fresh Air Systems
Air Handling Units (AHUs)
Ventilation Control Systems
Smart Building PM2.5 Monitoring
Commercial Indoor Air Quality Monitoring
Air Purification Systems
Public Building Air Quality Management

Application Areas

Residential and central air conditioning indoor air quality monitoring

Residential / Central Air Conditioning

Designed for residential and central air conditioning systems, this A54 configuration provides indoor air quality data to help HVAC, ventilation and purification systems respond more accurately to changing room conditions.

Fresh air and ventilation system monitoring

Ventilation Systems

Suitable for residential and commercial ventilation systems, the sensor provides stable data for airflow regulation, air exchange and indoor air quality management in long-running systems.