The dual RC18 PV reference cell soiling and irradiance kit, part numbers 810262-xx, provides a simple and low-cost solution for soiling measurement. Users wash one RC18 reference cell to keep it clean and allow the other one to collect soiling naturally. Soiling calculations are performed by the user from the collected irradiance data.

Attached to this article you'll find:

  • A kit datasheet, document 880082
  • A quick start guide for installation, document 880091. 

In addition, attached you'll find the following resources with examples of how to analyze the data:

  • Excel spreadsheet: This example Excel spreadsheet illustrates the calculation of daily soiling ratio using your logged data. You can use this spreadsheet and modify it for your own purposes, or just use it as an example to understand how to implement analysis in your own system.
  • Campbell Scientific CR1000X Datalogger Code: For users of the CR1000X datalogger, we have provided a sample code which logs two RC18 reference cells every minute, computes a daily sum of the irradiance readings from the clean and dirty cells, and outputs a soiling ratio value which is the ratio of the previous day's dirty / clean readings.