Author: Alicia Webb
Contributors: Chris Blanksby, Natalie Lukies
Once you've installed your mast and have anemometers and vanes measuring wind conditions, the logger at the base of the mast records the data. But gathering on-site wind data doesn't stop there. You can either get a consultant to collect and store this data, or your community group may choose to do it.
Your main tasks are to:
- collect, store and check the quality of the data
- identify any damage or faults that require maintenance
- carry out any necessary maintenance
- carefully record any changes to the monitoring system
- document an audit trail for all data
Collecting data
You'll receive data in different ways, depending on the type of logger you use. Options include:
- automatic telemetry that can email the data at specified intervals
- a computer program that can automatically telephone the logger and download the data to a specified folder
- you visit the site to manually change the data cards
- you visit the site and connect a computer to the logger to download data.
Whichever method you use, you should find helpful information in the logger manual, and have technical support from the people who installed your mast. We recommend you complete a log every time you receive data, and save the file with a clear file name.
It's important to log:
- date and time you received the data
- start and finish date and time of data
- next date and time you plan to retrieve data.
It's also important to note if you miss a scheduled data-retrieval date.
Storing data
It’s important you don't lose data if a computer crashes. The best way to store data is to create a folder on a reliable computer, and create a backup (or even multiple backups) on an external hard drive, a USB stick, or even on CD or DVD.
A good file name that keeps data in order and identifies it clearly is:
- SiteName (start date in yymmdd)_(finish date in yymmdd).txt.
- As an example, if a site is called ‘Hepburn’ and data is received for the period of 4 May 2010 to 3 June 2010, the file could be stored as Hepburn_100504_100603.txt
Checking data and identifying faults
Excel is a handy tool for checking data. It's worth looking at time series plots for all instruments in order to diagnose any breakdowns. You can make time series plots by highlighting the column of data you wish to view, and clicking ‘insert chart’ in Excel. Selecting a line graph is best.
Other instruments
Much like the fault detection process for anemometers and vanes, you should check temperature, humidity and pressure sensor data using a time series graph. It's important to look for:
- sudden changes
- periods of fixed values
- data which lies outside a reasonable range (for example, temperature values above or below a normal, expected temperature range for the area).
Mast maintenance
If your mast needs maintenance, it's worth contacting the people who installed it. A team can usually deal with maintenance issues in one or two days. Just remember to have replacement equipment on site the day the mast team arrives to do the work.
Maintenance reporting
It's vital you record any changes to the monitoring mast. Have a maintenance report which describes the work undertaken and the date. Update the installation report to reflect the new configuration and instrument serial numbers.
Calibration certificates for the anemometers are vital and should be annotated to show where and when the instrument was installed on the mast. They should be stored in a safe place and scanned and stored electronically with the data.