INSTRUCTION MANUAL CMP6-L, CMP10-L, CMP11-L and CMP21-L Pyranometers March 2015 Copyright © 2015 Campbell Scientific (Canada) Corp.
WARRANTY AND ASSISTANCE This equipment is warranted by CAMPBELL SCIENTIFIC (CANADA) CORP. ("CSC") to be free from defects in materials and workmanship under normal use and service for twenty-four (24) months from date of shipment unless specified otherwise. ***** Batteries are not warranted. ***** CSC's obligation under this warranty is limited to repairing or replacing (at CSC's option) defective products.
Table of Contents PDF viewers: These page numbers refer to the printed version of this document. Use the PDF reader bookmarks tab for links to specific sections. 1. Introduction ................................................................ 1 2. Cautionary Statements .............................................. 1 3. Initial Inspection ......................................................... 1 3.1 3.2 Ships With ..........................................................................................
Table of Contents 8. Maintenance ............................................................. 23 8.1 8.2 8.3 8.4 Cleaning Domes ................................................................................ 23 Changing the Desiccant ..................................................................... 24 Check Sensor Output ......................................................................... 24 Recalibration .....................................................................................
Tables TABLE 6-1. CMP-Series Specifications ........................................................ 7 TABLE 7-1. CMP6, CMP10 and CMP11 Differential Connections to Campbell Scientific Dataloggers .................................................... 13 TABLE 7-2. CMP6, CMP10 and CMP11 Single-Ended Connections to Campbell Scientific Dataloggers .................................................... 14 TABLE 7-3. CMP21 Differential Connections to Campbell Scientific Dataloggers ..................................
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers 1. Introduction CMP-series pyranometers are designed for continuous outdoor monitoring of solar radiation intensity. A flat spectral sensitivity from 285 to 2800 nm enables accurate measurements in natural sunlight, under plant canopies, and in green houses or buildings. When inverted, these pyranometers can measure reflected solar radiation. Uses include monitoring global horizontal irradiance (GHI) and plane of array irradiance (POA).
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers 3.1 Ships With (2) Bolts for mounting from original manufacturer (1) Sun Shield from original manufacturer (2) Nylon washers from original manufacturer 3.2 Calibration Certificate Each pyranometer is shipped with an instruction manual provided by Kipp & Zonen that contains information concerning its construction, spectral sensitivity, cosine response, and a simple sensor check out procedure.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers 4.2 Mounting See Section 7.1, Mounting to a Tripod Tower, for more information.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers Figure 4-3 Two views of a pyranometer mounted at an angle for the Northern Hemisphere Figure 4-4 Pyranometer mounted at an anlge for the Southern Hemisphere 4
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers 4.3 Datalogger Programming/Wiring The simplest method for programming the datalogger to measure a CMP6, CMP10 or CMP11 is to use Campbell Scientific's SCWin Short Cut Program Generator (see Figure 4.5). Wire the pyranometer according to the wiring diagram generated by Short Cut. Note The CMP21 is not included in Short Cut. Refer to Section 7, Installation, for wiring and programming information if not using Short Cut.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers 5. Overview 5.1 Models CMP-series models differ in accuracy and performance. See Section 6, Specifications. The CMP21 also includes an internal thermistor allowing individually optimized compensation of the measurements. The –L portion of the model number indicates that the pyranometer has a user-specified cable length. The pyranometers have several cable termination options. Their cables can terminate in: x x x 5.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers 6. Specifications 6.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers Figure 6-1 Dimensions of the CMP6, CMP11, and CMP21 6.2 CVF3 Ventilation Unit Compatible Pyanometers: CMP6, CMP10, CMP11, CMP21 Power supply: 12 Vdc, 1.3 A (with 10 W Heater) Operating temperature range: –40° to 70°C Ventilation power: 5 W continuously Heating power: 5 W and 10 W Heater induced offset: <1 W•m–2 (with CMP11 Pyranometer) Weight without cable: 1.6 kg (3.5 lb) Figure 6-2 Dimensions of the CVF3 6.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers Operating temperature range: –40° to 70°C Ventilation power: 5 W continuously Heating power: 5.5 W Heater induced offset: <1 W•m–2 (with CMP10, CMP11 Pyranometer) Weight without cable: 1.6 kg (3.5 lb) Figure 6-3 Dimensions of the CVF4 7. Installation 7.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers Note If using a CFV3 or CVF4 Ventilation Unit, a different mounting stand, the 27084 is required. Refer to Appendix A, CVF3 and CVF4 Heater/Ventilator, for more information. The CM245 includes slots that allow it to be adjusted to any angle from horizontal to vertical. If mounting the pyranometer at an angle, ensure that the crossarm is leveled horizontally before placing the bracket at its proper angle.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers First 1.5” u-bolt 40 Second 1.5” u-bolt Figure 7-2 CM245 bracket with 1.5" u-bolts positioned to mount pyranometer at a 40° angle on a vertical pipe Do the following to level the pyranometer horizontally (see Error! Reference ource not found.): 1. Attach the mounting stand to the crossarm. 2. Loosely mount the pyranometer on the mounting stand. Do not fully tighten the two mounting screws. 3.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers Sun shield Mounting screws Nylon washers Bubble level Pyranometer Levelling screw CM245 mounting stand Crossarm 6. Figure 7-3 Exploded view of the pyranometer mounting 7.2 Wiring Note Short Cut users should wire the sensor according to the wiring diagram generated by Short Cut. The cable of the CMP6, CMP10 and CMP11 has two conductors and a shield. The cable of the CMP21 has five conductors and a shield.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers 7.2.1 CMP6, CMP10, CMP11, and CMP21 Thermopile Schematic A schematic diagram of a CMP6, CMP10, CMP11, or CMP21 thermopile is shown in Figure 7-4. Red White (+) Blue Black (-) Black Shield Figure 7-4 CMP6, CMP10, CMP11, or CMP21 thermopile detector schematic 7.2.2 CMP6 and CMP11 Wiring Note CMP6, CMP10, or CMP11 purchased from Campbell Scientific has different wiring than a pyranometer purchased directly from Kipp & Zonen.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers TABLE 7-2. CMP6, CMP10 and CMP11 Single-Ended Connections to Campbell Scientific Dataloggers Color Description CR9000(X), CR5000, CR3000, CR1000, CR800 White Signal (+) SE Analog Black Signal (–) AG Clear Shield G CR510, CR500, CR10(X) 21X, CR7, CR23X SE Analog SE Analog 7.2.3 CMP21 Wiring Note A CMP21 purchased from Campbell Scientific has different wiring than a CMP21 purchased directly from Kipp & Zonen.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers TABLE 7-4.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers Select the input range as follows: 1. Estimate the maximum expected input voltage by multiplying the maximum expected irradiance (in W•m–2) by the calibration factor (in μV / W•m–2). Divide the answer by 1000 to give the maximum in millivolt units. 2. Select the smallest input range which is greater than the maximum expected input voltage.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers 7.3.1.3 Offset The offset will normally be fixed at zero as the sensor should output no significant signal in dark conditions. In practice, because of the nature of thermopile detector sensors, there will be some offset in dark conditions; sometimes this offset can give negative light readings. This offset varies with several factors (e.g., rate of change of sensor temperature), so it cannot be removed with a fixed offset.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers In CRBasic, the conversion to resistance is entered as a mathematical expression. In Edlog, Instruction P59 (Bridge Transform) does the conversion. The Steinhart-Hart equation is used to convert resistance to temperature. The Steinhart-Hart equation for converting resistance to degree Celsius is as follows: Temperature = 1/[A + B*LN(resistance) + C*(LN(resistance))^3] - 273.15 Where A, B, and C are coefficients for the Steinhart-Hart equation.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers 'Measure the Battery Voltage and Panel Temperature PanelTemp (PTemp,250) Battery (Batt_Volt) 'Measure the CMP6 VoltDiff (CMP6_Irr,1,mV25C,1,True ,10000,_60Hz,1000/14.33,0) CallTable TenMin NextScan EndProg 7.3.3.2 CR1000 Example Program for Measuring a CMP11 Although this example is for the CR1000, other CRBasic dataloggers are programmed similarly. The following program measures the CMP11 every second and converts the millivolt output to W•m–2.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers Battery (Batt_Volt) 'Measure the CMP11 VoltDiff (CMP11_Irr,1,mV25C,2,True ,10000,_60Hz,1000/8.55,0) CallTable TenMin NextScan EndProg 7.3.3.3 CR1000 Example Program for Measuring a CMP21 Although this example is for the CR1000, other CRBasic dataloggers are programmed similarly. The following program measures the CMP21 every second. It converts the pyranometer’s millivolt output to W•m–2. A pyranometer calibration of 8.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers BeginProg Scan (1,Sec,0,0) ‘Measure the Battery Voltage and Panel Temperature PanelTemp (PTemp,250) Battery (Batt_Volt) ‘Measure the CMP21 pyranometer VoltDiff (CMP21_Irr,1,mV25C,3,True,10000,_60Hz,1000/8.65,0) 'CMP21 Thermistor Measurement BrHalf (Vs_Vx,1,mV5000,15,Vx1,1,2500,True ,0,250,1.0,0) Rs = 1000*(Vs_Vx/(1-Vs_Vx)) CMP21_T_C = 1/(1.0295e-3+2.391e-4*LN(Rs)+1.568e-7*(LN(Rs))^3)-273.15 'Convert CMP21 temp to Kelvin. CMP21_T_K = CMP21_T_C+273.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers ;{CR10X} *Table 1 Program 01: 10.0000 Execution Interval (seconds) ; CMP6 measurement in W/m2 1: Volt (Diff) (P2) 1: 1 2: 23 3: 1 4: 3 5: 69.7837 6: 0 Reps 25 mV 60 Hz Rejection Range DIFF Channel Loc [ Solar_Wm2 ] Multiplier Offset ;use the 50 mV range for the CR7, 21X and CR23X ;use the 250 mV range for the CR10X if ;calibration factor is > 25 μV/Wm-2 ;1000/14.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers 11: Set Active Storage Area (P80) 1: 1 Final Storage Area 1 2: 102 Array ID 12: Real Time (P77) 1: 1220 Year,Day,Hour/Minute (midnight = 2400) 13: Resolution (P78) 1: 1 High Resolution 14: Totalize (P72) 1: 1 Reps 2: 4 Loc [ Solar_MJ ] 15: Resolution (P78) 1: 0 Low Resolution 8. Maintenance At regular intervals, physically inspect the pyranometer to ensure that: 8.1 x Dome is free of dirt, condensation, and ice (see Section 8.1, Cleaning Domes).
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers 8.2 Changing the Desiccant A desiccant-filled drying cartridge prevents dew from forming on the inner sides of the domes; Campbell Scientific part number 27052 is the replacement desiccant for this cartridge. The optional CVF3 or CVF4 Heater/Ventilator Unit is also available to keep the pyranometer dome free from ice and dew (see Appendix A, CVF3, CVF4 Heater/Ventilator).
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers pyranometers can fall as low as 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, which results in an infra-red emission of –150 W•m–2. If this happens, dew, glazed frost or hoar frost can be precipitated on the top of the outer dome and can stay there for several hours in the morning.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers 26
Appendix A. CVF3, CVF4 Heater Ventilator A.1 General Information Note The CVF3 has been discontinued and replaced by the CVF4. The CVF3 and CVF4 consist of a ventilation unit and heaters. The 5 W ventilation unit uses a fan and inlet filter to draw clean air over the pyranometer’s domes. The fan runs continuously to reduce dust and dirt settling, to dissipate rain drops, and to stabilize the dome temperature. The CVF3 has both a 5 W and a 10 W heater. The CVF4 has a 5.5 W heater.
CVF3, CVF4 Heater Ventilator A-2 Transparent front view of CVF4 showing air flow A-3 Tranparent side view of CVF4 showing air flow A.3 Installation The CVF3 or CVF4 unit includes the heater/ventilator unit, white cover, cable, and mounting hardware.
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers x Compass x Step ladder A.3.1 CVF3 To install, do the following: 1. Remove leveling screws from the pyranometer. 2. Fit the pyranometer in the upper plate of the CVF3 (see Figure A-4). 3. Use the counter sink screws, nylon rings, and nuts to secure the upper plate of the CVF3 with the lower portion of the unit (see Figure A-4). Nylon Ring A-4 Pyranometer mounted to the CVF3 4. Loosely mount the pyranometer on the 27084 mounting stand.
CVF3, CVF4 Heater Ventilator A-5 CVF3 installed onsite 6. Tighten the mounting screws to secure the assembly in its final position. Check that the pyranometer is still correctly leveled and adjust as necessary. 7. Use the cover’s screws to fasten the white cover to the pyranometer (see Figure A-6).
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers 8. Attach the power cable to the CVF3 connector. A.3.2 CVF4 Installation To install, do the following: 1. Screw the CVF4 flat onto the mounting plate. Be sure to position the CVF4 so that the fan sticks out over the edge of the plate. See Figure A-7 for the CVF4 mounting holes size and distances. The CVF4 is mounted with the supplied washers and screws to the L31153 mount. Please note that 4 sets of mounting hardware are included to mount the CVF4.
CVF3, CVF4 Heater Ventilator A-8 L31153 Mounted CVF4 A-6
CMP6-L, CMP10-L, CMP11-L, and CMP21-L Pyranometers A.4 Wiring Wiring of the CVF3 is shown in Table A-1. Refer to Section 7.2, Wiring, for information about wiring the pyranometer.
CVF3, CVF4 Heater Ventilator A-9 CVF3 filter replacement A.5.2 CVF4 Note Regular inspection of the CVF4 is advised. Depending on location (air pollution) this can be monthly or yearly. Remember to check the CVF4 filter. 1. Refer to Section 8, Maintenance, for pyranometer’s maintenance. 2. For access to the desiccant, the 2 mounting nuts have to be loosened and the top cover taken off.
A-1
