FOR UNATTENDED DIRECT NORMAL INCIDENCE SOLAR RADIATION MEASUREMENT Classical passive model with mV output, or Smart version with Enhanced performance by digital signal processing RS-485 serial data interface with Modbus® protocol

Introduction Solar radiation is the driving force behind biological and geophysical processes in meteorology, climate and our environment. The sun irradiates the top of the earth’s atmosphere at an average intensity of 1367 W/m². As the solar rays travel through our atmosphere they are absorbed and scattered. This results in different components of solar radiation reaching the earth’s surface. The direct component travels in a straight beam from the sun, whilst a diffuse component comes from all directions, due to the atmospheric scattering process. A pyrheliometer is an instrument designed specifically...

Interfacing The CHP 1 has a maximum output of 25 mV output under atmospheric conditions and requires a data logger with an analogue input of at least 12 bits resolution over that range. The CHP 1 does not need a power supply. The analogue outputs allow easy connection to virtually any data logger without the need for sensitive mV inputs. Modbus® interfaces directly to RTU’s, PLC’s, SCADA systems, industrial networks and controllers. The SHP1 is equipped with a smart interface. There are two versions, one has an analogue output of 0 to 1 V, the other of 4 to 20 mA. Both have a 2-wire RS-485 interface...

First Class First Class Zero offsets due to temperature change (5 K/hr) Non-stability (change/year) Temperature dependence of sensitivity Analogue output Analogue output range Digital output Operating temperature Full viewing angle Maximum irradiance Spectral range (50 % points) Required sun tracker accuracy Other specications Weight (excluding cable) Slope angle Temperature sensor Both Pt-100 and 10k thermistor as standard (2) Supply voltage Expected daily uncertainty Calibration certicate traceable to WRR, multi-language instruction sheet, manual on CD-ROM Recommended applications High performance...