Cloud Sensor
SEVEN Cloud Sensor is a specialized device designed to measure cloud coverage for commercial and industrial photovoltaic (PV) systems. By analyzing cloudiness, it helps determine whether solar panels should stay fixed or adjust to the sun’s position, optimizing energy efficiency.The system includes two Irradiance Sensors—one always shaded and one always exposed—along with a shading band and mounting components. The shaded sensor measures Diffuse Irradiance, while the exposed sensor measures Plane of Array Irradiance (POA), following IEC 61724 standards. The Cloudiness Ratio is calculated from the ratio of these two values.Data is transmitted via RS485 using the Modbus RTU protocol to data loggers or monitoring systems.
Measured Parameters:
POA Irradiance – Total of direct, diffuse, and reflected sunlight on PV panels.
Diffuse Irradiance – Indirect sunlight scattered by clouds and atmosphere.
Direct Irradiance – Sunlight directly from the sun.
Cloudiness Ratio – Diffuse Irradiance divided by POA; calculated both instantly and as a daily average.
TECHNICAL DATA
| Item Code | 3S-CS-MB |
| Measurable Data | Plane of Array (POA) Irradiance, Diffuse Irradiance on Panel Tilt, Direct Irradiance on Panel Tilt, Cloud Cover Ratio |
| Cloud Cover Ratio Range | 0 … 100% |
| Cloud Cover Ratio Resolution | 5% |
| Output Rate | 1/s |
| Data Output | RS485 up to 38400 baud |
| Communication Protocol | Modbus RTU |
| Power Supply | 12 … 30 V DC |
| Power Consumption | 25 mA max @ 24 V DC |
| Cable Length & Features | 3 meters 3x2x0.22mm, 24 AWG (UV and Weather Resistant) |
| Galvanic Isolation | 1000 V Between Power Supply and RS485 Data Bus |
| Operating Temperature Range | -40°C … +85°C |
| Operating Humidity Range | 0 … 100%RH |
| Dimensions | 550 mm x 500 mm x 310 mm (W x L x H) |
| Sensor Weight | 4.2 kg |
| IP Rating | IP54 (Optional IP 65, IP 68) |
| Sensor Housing Material | Aluminum |
| Shading Band | FBE Epoxy Coated Steel |
| Standard | IEC 61724-1:2021 and IEC 60904 |
| Calibration | Each sensor is calibrated under an AAA Class Solar Simulator according to IEC 60904- 2 and IEC 60904-4 standards using a reference cell calibrated by the ISFH Institute in Germany. |