8.2.7 Radiation
A
simple functional test of a pyranometer or solarimeter can be conducted with
an electrical light bulb. With the sensor connected to the system as it will
be in the field, cover it completely with a box with all cracks taped with
an opaque tape. Any light can bias a "zero" check. The output
should be zero. Do not make any adjustments without being absolutely sure
the box shields the sensor from any direct, reflected, or diffuse light.
Once the zero is recorded, remove the box and bring a bulb (100 watt or
similar) near the sensor. Note the output change. This only proves that the
wires are connected properly and the sensor is sensitive to light.
If
a net radiometer is being checked, the bulb on the bottom should induce a
negative output and on the top a positive output. A "zero" for a
net radiometer is much harder to simulate. The sensor will (or may) detect
correctly a colder temperature on the bottom of the shielding box than the
top, which may be heated by the light fixtures in the room. Check the
manufacturer's manual for guidance.
8. QUALITY ASSURANCE AND QUALITY CONTROL
8.1 Instrument Procurement
8.1.1 Wind Speed
8.1.2 Wind Direction
8.1.3 Temperature and Temperature Difference
8.1.4 Dew Point Temperature
8.1.5 Precipitation
8.1.6 Pressure
8.1.7 Radiation
8.2 Installation and Acceptance Testing
8.2.1 Wind Speed
8.2.2 Wind Direction
8.2.3 Temperature and Temperature Difference
8.2.4 Dew Point Temperature
8.2.5 Precipitation
8.2.6 Pressure
8.2.7 Radiation
8.3 Routine Calibrations
8.3.1 Sensor Check
8.3.2 Signal Conditioner and Recorder Check
8.3.3 Calibration Data Logs
8.3.4 Calibration Report
8.3.5 Calibration Schedule/Frequency
8.3.6 Data Correction Based on Calibration Results
8.4 Audits
8.4.1 Audit Schedule and Frequency
8.4.2 Audit Procedure
8.4.3 Corrective Action and Reporting
8.5 Routine and Preventive Maintenance
8.5.1 Standard Operating Procedures
8.5.2 Preventive Maintenance
8.6 Data Validation and Reporting
8.6.1 Preparatory Steps
8.6.2 Levels of Validation
8.6.3 Validation Procedures
8.6.4 Schedule and Reporting
8.7 Recommendations
