John your solar readings should vary throughout the day from sunrise to sunset, you can see what the expected values should be by using this script at http://www.stella-maris.org.uk/maxsolar.php. Just make sure you have entered your lat/long and timezone correctly and it will display the expected values for your location. Also may I suggest you take a look at http://discourse.weather-watch.com/t/14558.
Having checked all this out, if it still seems wrong then perhaps a screen shot of your solar control panel might help.
Stuart