The solar clock object computes Present Value (Night/Day), Sun Position (Azimuth and Elevation), and Sunrise and Sunset times based on the local position (Latitude and Longitude) and local time and time zone information. This information is needed to control external motorized louvers as part of bioclimatic facades for buildings and may also be used to position tracking photovoltaic solar arrays. The Sunrise/Sunset times can be used for external lighting control.
This object runs on a periodic basis to compute its attributes. The equations to compute azimuth, elevation, sunrise, and sunset attributes were obtained from the National Oceanic and Atmospheric Administration (NOAA) Web site (http://www.noaa.gov/). The object obtains the Local Time, UTC Offset, DST Status, and DST Offset from the BACnet Device object.
Latitude and Longitude for this object are provided in decimal degrees. Often, these values are provided as degrees, minutes, and seconds. There are numerous Web sites that can convert the latitude and longitude values, if necessary. In addition, you can obtain your current location on the planet from free tools such as Google Earth. Google Earth includes an option to provide your location in decimal degrees.
|Milwaukee, WI, USA
|Brengel Technology Center
|Notre Dame Cathedral
|Cape Town, South Africa
|Green Point Stadium
For general information on Metasys system objects, see Common Object Attributes.