Kipp & Zonen SMP series Instruction Manual

Also see for SMP series: Quick start guide

Kipp & Zonen SMP series Instruction Manual Manual pdf 16 page image

Lower screen (white)Mast (black)EquatorHR SDPyranometer.2.4.6 Fitting the connector and cableLocate the plug correctly in the radiometer socket, it only fits one way, and push it in. Screw the plug locking ring hand-tight.Over-tightening may damage the waterproof seal. Secure the cable so that it cannot blow in the wind or cause a shadow on theinstrument.Note The cable should be arranged with a curve below the instrument so that water drips off, rather than running alongthe cable up to the connector.2.4.7 Fitting the sun shieldFinally, clip on the sun shield to prevent excessive heating of the radiometer body. The bubble level is visible through the topof the sun shield for routine checks and the shield ‘tail’ helps to protect the connector.2.5 Installation for measurement of tilted global irradianceWhen a pyranometer is mounted on a large flat tilted surface the temperature of this surface can rise considerably (more than10 °C) above air temperature. It is advised to pre-adjust the levelling feet on a horizontal surface for easy mounting of theinstrument parallel to the inclined surface. It improves the measurement accuracy when the body is thermally isolated by itsfeet from the surface. This promotes thermal equilibrium between the dome(s) and the housing and decreases zero offsets.For accurately and securely fixing a pyranometer at an angle to a surface an adjustable tilt mounting kit is available. See Accessoriesin chapter 3.2.6 Installation for measurement of reflected global irradianceIn the inverted position the pyranometer measures reflected global radiation. Theheight above the surface (H) depends upon its roughness. The WMO recommends aheight of 1 m to 2 m above a uniform surface covered by short grass.The mounting device should not interfere significantly with the field of view of theinstrument. The mounting plate above the pyranometer prevents excessive heating ofthe housing by downwards solar radiation and. The glare screen has an angle of 5 °and is fitted to the pyranometer to prevent direct illumination of the domes by the sunat sunrise and sunset. It is available as an accessory kit for all SMP’s except the SMP3.Thermal offset signals generated in the pyranometer are 5 times more significantin the measurement of reflected radiation due to the lower irradiance level.The mast shown intercepts a fraction D/2πS. of the radiation coming from theground. In the most unfavourable situation (sun at zenith) the pyranometershadow decreases the signal by a factor R2/H2.As a guide, a black shadow below the pyranometer with a radius of 0.1 x H decreases the signal by 1%, and 99 % of the signalwill originate from an area with a radius of 10 x H.16