Calibration Facility

What it's for

CFR offers a solution for quality control of the stability of the pyranometers used in a network, using a reference pyranometer as the basis for comparison. Periodic recalibration of radiometers is recommended, as the sensitivity of a pyranometer can change naturally over time; ESS advises recalibration every two years.

Why on-site calibration

For customers with a large number of pyranometers and/or albedometers, or who maintain an instrument network, sending units back to Kipp & Zonen's Delft facility for regular recalibration creates down-time and logistical effort. The CFR complies with the ISO 9847 international standard, giving a high-accuracy, on-site calibration alternative.

Calibration procedure

The procedure used complies with Annex A.3 of international standard ISO 9847 "Calibration of Field Pyranometers by Comparison to a Reference Pyranometer"; Annex A.3 refers to "Calibration Devices Using Artificial Sources". The facility is manually operated and the time needed for each calibration is approximately 10 minutes. Preparation for a measurement session, including warm-up and stabilisation of the calibration lamp, will take about 30 minutes. The calibration transfer uncertainty between reference and test pyranometers of high quality, such as the CMP 11, is estimated to be ± 1%.

Turntable and reference pyranometers

The turntable supplied with the CFR is suitable for calibration of CM 6, 11, 21, 22, 31 and CMP 3, 6, 10, 11, 21, 22 pyranometers. Adaptors and alternative turntables are available to suit other pyranometers and albedometers. CFR is supplied without reference pyranometers; these should be purchased separately and be of similar characteristics to the field radiometers under test.

Installation and technician training