Solar PV module soiling sensor 3S-SMS-P

for photovoltaic applicationsopticalportable

Overview
The Portable Soiling Sensor is developed by SEVEN Sensor and uses patented optical technology to quantify soiling levels on photovoltaic (PV) panels in the field. The instrument provides on-site soiling ratio measurements to support cleaning decisions and O&M planning.

How it works
The sensor measures reflected and scattered light from the panel surface. Internal lamps illuminate the module and high-precision detectors capture the reflected signal. Users set panel cell color and dust parameters via the integrated LCD touchscreen. An internal microcontroller processes the signals and displays the soiling ratio on the screen.

Measurement procedure

• Take three readings on the soiled panel: bottom-center, middle, top-center
• Thoroughly clean the same panel
• Take three readings again at the same positions

The device uses the before-and-after readings to compute a consistent soiling ratio for that module.

Supported panel and dust parameters
Panel cell color: black or blue
Dust color: brown, white, or gray
Dust tone: light, medium, or dark

Who typically uses the 3S-SMS-P

• Cleaning contractors identifying areas that require intervention
• PV plant owners and O&M teams managing multiple sites
• Operators managing fleets across different climates seeking a consistent method

Key benefits

• Portable and field-ready for spot measurements
• Instant results on integrated LCD without external software for routine checks
• Consistent soiling ratio calculation across panel and dust colors
• Patent-pending technology tailored to PV soiling measurement
• Supports rapid cleaning prioritization and decision making
• Firmware/software updates and SEVEN Sensor support available

Additional product information
Routine measurements are displayed on the LCD and are not stored locally by default. Recommended recalibration: every 500 hours of use or every 2 years. Standard delivery: portable sensor head, battery box, charger adapter, power cable, communication cable, USB‑to‑RS485 converter; optional carrying case may be available.

Technical specifications

• Item code: 3S-SMS-P
• Soiling ratio measurement range: 2% – 20%
• Resolution: 0.1%
• Uncertainty: ≤ 2%
• Data output: RS485
• Operating temperature: −10°C to +50°C
• Operating humidity: 0 … 90 % RH
• Power supply: 12 V, 24 Ah lithium battery
• Working time: 5 hours
• Battery charging time: 3 hours
• Sensor dimensions: Ø 280 mm x 180 mm (D x H)
• Sensor weight: 4 kg
• Battery box dimensions: 220 mm x 232 mm x 137 mm (W x L x H)
• Battery box weight: 3.6 kg