CMA series Albedometer CMP series Pyranometer Instruction Manual
IMPORTANT USER INFORMATION Reading this entire manual is recommended for full understanding of the use of this product. Should you have any comments on this manual we will be pleased to receive them at: Kipp & Zonen B.V. Delftechpark 36, 2628 XH Delft, The Netherlands or P.O. Box 507, 2600 AM Delft, The Netherlands T F E W : : : : +31 (0)15 2755210 +31 (0)15 2620351 info@kippzonen.com www.kippzonen.com Kipp & Zonen reserves the right to make changes to the specifications without prior notice.
Declaration of Conformity According to EC guideline 89/336/EEC 73/23/EEC We Kipp & Zonen B.V.
CMP/CMA series manual Table of Contents IMPORTANT USER INFORMATION ....................................................................................................... 1 Declaration of Conformity ......................................................................................................................... 2 Table of Contents ..................................................................................................................................... 3 1. Introduction ..................
CMP/CMA series manual 6.3. CMP 21 ........................................................................................................................................ 24 6.4. CMP 22 ........................................................................................................................................ 24 6.5. CMP / CMA series performance specifications ........................................................................... 25 6.6. CMP / CMA series general specifications ............
CMP/CMA series manual 1. Introduction Dear customer, thank you for purchasing a Kipp & Zonen instrument. Please read this manual and the separate instruction sheet for a full understanding of the use of your pyranometer or albedometer.
CMP/CMA series manual 2. Installation and operation 2.1. Delivery Check the contents of the shipment for completeness (see below) and note whether any damage has occurred during transport. If there is damage, a claim should be filed with the carrier immediately. In this case, or if the contents are incomplete, your dealer should be notified in order to facilitate the repair or replacement of the instrument. Contents of delivery: 1. 2. 3. 4. 5. 6. 7. 8.
CMP/CMA series manual This is important for an accurate measurement of the direct solar radiation. The diffuse solar radiation is less influenced by obstructions near the horizon. For instance, an obstruction with an elevation of 5o over the whole azimuth range of 360o decreases the downward diffuse solar radiation by only 0.8%.
CMP/CMA series manual 5. Level pyranometer Accurate measurement of the global radiation requires proper levelling of the thermopile surface. Level the instrument by turning the two levelling screws to bring the bubble of the spirit level centrally within the marked ring. For easy levelling, first use the screw nearest to the spirit level.
CMP/CMA series manual 2.2.4. Installation for measurement of diffuse radiation For measuring sky radiation, the direct solar radiation is intercepted by a small disk or sphere. The shadow of the disk must cover the pyranometer domes completely. However, to follow the sun's apparent motion, a power-driven tracking device is necessary as shown in Figure 3. This can be done using a Kipp & Zonen sun tracker, such as the model 2 AP, designed to track the sun accurately under all weather conditions.
CMP/CMA series manual 2.3. Electrical installation As standard the CMP/CMA is supplied with a waterproof connector pre-wired to 10 m cable with a number of leads and a shield covered with a black sleeve. The number of connector pins and cable leads depends upon the model of radiometer and whether a temperature sensor is fitted (and which type). The colour code of the wires and the connector pin numbers are shown on the instruction sheet. Longer cables are available as options.
CMP/CMA series manual 2.4. Operation After completing the installation the radiometer will be ready for operation. The irradiance value (E↓Solar) can be simply calculated by dividing the output signal (Uemf) of the pyranometer by its sensitivity (Sensitivity) as shown in Formula 1.
CMP/CMA series manual The temperature dependence of the sensitivity is a function of the individual CMP 22. For a given CMP 22 the response lies in the region between the curved lines in Figure 6. The temperature dependence of each CMP 21 and CMP 22 pyranometer is characterised and supplied with the instrument. Each CMP 21 and CMP 22 has a built-in temperature sensor to allow corrections to be applied if required.
CMP/CMA series manual 2.6. Maintenance Once installed the radiometer needs little maintenance. The outer dome(s) must be cleaned and inspected regularly, ideally every morning. On clear windless nights the outer dome temperature of horizontally placed radiometers will decrease, even to the dew point temperature of the air, due to infrared radiation exchange with the cold sky. (The effective sky temperature can be 30°C lower than the ground temperature).
CMP/CMA series manual 3. Principle components of pyranometers The detector of the Kipp & Zonen CMP/CMA series pyranometer is based on a passive thermal sensing element called a thermopile. Although the detector construction differs from model to model, the fundamental working principle is applicable to all CMP/CMA series radiometers. The thermopile responds to the total power absorbed by the black surface coating, which is a nonspectrally selective paint, and warm up.
CMP/CMA series manual 3.2. Detector The thermopile sensing element is made up of a large number of thermocouple junction pairs connected electrically in series. The absorption of thermal radiation by one of the thermocouple junctions, called the active (or ‘hot’) junction, increases its temperature.
CMP/CMA series manual 4. Pyranometer physical properties 4.1. Spectral range The spectrum of the solar radiation reaching the Earth’s surface is in the wavelength range between 280 nm and 4000 nm, extending from ultraviolet (UV) to the far infrared (FIR) as shown in Figure 9. Due to the excellent physical properties of the glass dome and black absorber paint, Kipp & Zonen CMP/CMA series radiometers are equally sensitive in a wide spectral range.
CMP/CMA series manual 4.5. Non-linearity The non-linearity of a radiometer is the percentage deviation in the sensitivity over an irradiance range from 0 to 1000 W.m-2 compared to the sensitivity calibration irradiance of 500 W.m-2. The non-linearity effect is due to convective and radiative heat losses at the black absorber surface which make the conditional thermal equilibrium of the radiometer non-linear. 4.6.
CMP/CMA series manual 4.9. Zero offset B Proportionally to the ambient temperature the instrument temperature varies and causes heat currents inside the instrument. This will cause an offset commonly called Zero Offset type B. It is quantified as the response in W/m2 to a 5 K/hr change in ambient temperature. 4.10. Operating temperature The operating temperature range of the radiometer is determined by the physical properties of the individual parts.
CMP/CMA series manual 4.14. Non-stability This is the percentage change in sensitivity over a period of one year. This effect is mostly due to degradation by UV radiation of the black absorber paint on the sensing element surface. Kipp & Zonen recommends recalibration every two years. However, for quality assurance purposes some institutes, companies or networks may require more or less frequent recalibration. Please read the chapter on the calibration procedure for pyranometers for more information. 4.
CMP/CMA series manual 5. Calibration 5.1. Calibration principle An ideal radiometer gives voltage output that is proportional to the absolute irradiance level. This relationship can be expressed as a constant ratio called ‘sensitivity’ (Sensitivity). The sensitivity figure of a particular radiometer is unique. It is determined in the manufacturer's laboratory by comparison against a reference radiometer of similar type.
CMP/CMA series manual 5.2.3. Calculation The sensitivity of the unknown pyranometer is calculated with formula 2: S Sb A A’ B B’ Sa a = A + A' ⋅ B + B ' sb Formula 2 = Sensitivity of the reference radiometer at +20 °C. = Output of test radiometer at position 1 = Output of test radiometer at position 2 = Output of reference radiometer at position 2 = Output of reference radiometer at position 1 = Sensitivity of the test radiometer at +20 °C.
CMP/CMA series manual There are several procedures for transferring calibration from a narrow field of view instrument (pyrheliometer) to a wide field of view instrument (pyranometer). For example the direct component of the solar radiation is eliminated temporarily from the pyranometer by shading the whole outer dome of the instrument with a disk. There is however no thermal equilibrium with this method and some pyranometer models show zero-offset drift.
CMP/CMA series manual 6. CMP/CMA models The CMP series offers 5 different models in the range from CMP 3 up to CMP 22. The mechanical construction of the CMP 3 differs from the others in that it has a single dome, smaller housing dimensions and no drying cartridge (the housing is completely sealed). Features and specification of the double dome pyranometers in the range from CMP 6 to CMP 22 are specified in this chapter.
CMP/CMA series manual 6.3. CMP 21 CMP 21 is a high precision scientific pyranometer based upon the CMP 11 but with individual optimisation and characterisation and an integrated housing temperature sensor. CMP exceeds the ISO-9060 specification criteria for an ISO Secondary Standard pyranometer The special features of the CMP 21 are: • • • Individually optimised and characterised temperature dependence. Individually characterised directional response. Integrated housing temperature sensor. 6.4.
CMP/CMA series manual 6.5. CMP / CMA series performance specifications Specification Unit CMP 6/ CMA 6 CMP 11 / CMA 11 CMP 21 CMP 22 Spectral range Sensitivity Impedance µm µV/W/m² Ω 310 - 2800 7 to 14 10 to 100 <5 < 1.7 < 0.2 310 - 2800 7 to 14 10 to 100 <5 < 1.7 < 0.2 200 - 3600 7 to 14 10 to 100 <5 < 1.7 < 0.2 Response time s Non-linearity % 310 - 2800 5 to 18 20 to 200 < 18 < 6 <1 Temperature dependence of sensitivity % <4 <1 < 1* < 0.
CMP/CMA series manual 6.6.
CMP/CMA series manual 7. Frequently asked questions The most frequently asked questions are listed below. For an update refer to the Kipp & Zonen website at www.kippzonen.com Negative output during night-time measurements? This error is related to Zero Offset type A. Normally this zero offset is present when the inner dome has a different temperature from the cold junctions of the sensor. Practically this is always the case when there is a clear sky.
CMP/CMA series manual 8. Trouble shooting The following contains a procedure for checking the instrument in case it appears that it does not function as it should. Trouble shooting: Output signal fails or shows improbable results: Check the wires are properly connected to the readout equipment. Check the instrument location. Are there any obstructions that cast a shadow on the instrument by blocking the direct sun during some part of the day? Check the dome, it should be clear and clean.
CMP/CMA series manual Appendix I Radiometric terminology Term Explanation Albedo The portion of incoming radiation which is reflected by a surface Azimuth angle Angle in horizontal direction (0-360°) Angle of incidence Incident angle from zenith (vertical) Cosine response Detector response according to the cosine law Diffuse solar irradiance Solar radiation, scattered by water vapor, dust and other particles as it passes through the atmosphere Direct solar irradiance Radiation that has travell
CMP/CMA series manual Appendix II 10k thermistor specifications YSI Thermistor 44031 - Resistance versus Temperature in °C YSI 44031 Temperature vs. Resistance Temperature Resistance Temperature Resistance Temperature Resistance [ °C ] -30 -29 -28 -27 -26 -25 -24 -23 -22 -21 -20 -19 -18 -17 -16 -15 -14 -13 -12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 [ °F ] [ Ohm ] -22.0 135,200 -20.2 -18.4 -16.6 -14.8 -13.0 -11.2 -9.4 -7.6 -5.8 -4.0 -2.2 -0.4 1.4 3.2 5.0 6.8 8.6 10.4 12.2 127,900 121,100 14.0 15.8 17.
CMP/CMA series manual Appendix III Pt-100 specifications Pt-100 - Resistance versus Temperature in ºC and ºF Pt-100 Temperature vs. Resistance Temperature Resistance Temperature Resistance Temperature Resistance [ °C ] -30 -29 -28 -27 -26 -25 -24 -23 -22 -21 -20 -19 -18 -17 -16 -15 -14 -13 -12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 [ °F ] -22.0 -20.2 -18.4 -16.6 -14.8 -13.0 -11.2 -9.4 -7.6 -5.8 -4.0 -2.2 -0.4 1.4 3.2 5.0 6.8 8.6 10.4 12.2 14.0 15.8 17.6 19.4 21.2 23.0 24.8 26.6 28.4 30.2 [ Ohm ] 88.2 88.
CMP/CMA series manual Appendix IV classification According to WMO Guide 1996 Characteristics ISO 9060 classification Response time (95 percent response) CMP 22 CMP 21 CMP 11 CMA 11 CMP 6 CMA 6 High quality Good quality Moderate quality Secondary standard Secondary standard Secondary standard First class Secondary standard First class Second class 5s 5s 5s 18 s < 15 s < 30 s < 60 s ± 3 W/m2 ± 7 W/m2 ± 7 W/m2 ± 15 W/m2 ± 7 W/m2 ± 15 W/m2 ± 30 W/m2 ± 1 W/m2 ± 2 W/m2 ± 2 W/m2 ±
CMP/CMA series manual Appendix V List of World and Regional Radiation Centres World Radiation Centres Davos (Switzerland) St. Petersburg (Russia) (data centre only) Region I (Africa) - Cairo (Egypt) - Khartoum (Sudan) - Kinshasa (Dem. Rep.
CMP/CMA series manual Appendix VI Recalibration service Pyranometers, Albedometers, Pyrgeometers, UV-Radiometers & Sunshine Duration Sensors Kipp & Zonen solar radiation measurement instruments comply with the most demanding international standards. In order to maintain the specified performance of these instruments, Kipp & Zonen recommends calibration of their instruments every two years. This can be done at the Kipp & Zonen factory.
Our customer support remains at your disposal for any maintenance or repair, calibration, supplies and spares. Für Servicearbeiten und Kalibrierung, Verbrauchsmaterial und Ersatzteile steht Ihnen unsere Customer Support Abteilung zur Verfügung. Notre service 'Support Clientèle' reste à votre entière disposition pour tout problème de maintenance, réparation ou d'étalonnage ainsi que pour les accessoires et pièces de rechange.
