Echelon SmartServer 2.2 - Manual (Page 361)

362 Scheduling
the maximum of 15 minutes.
Time Zone Displays the time zone in which the SmartServer is located. You can click
the displayed time zone to access the Setup – Time Web page. From this
Web page, you can select a different time zone.
Date and Local
Time Displays the time and date currently stored in the real time clock. You can
click the displayed time to access the Setup – Time Web page. From this
Web page, you can enter a different time to be stored in the real-time
clock.
Astronomical
Position Sensor
Property
Latitude Enter the north-south location of the SmartServer relative to the equator.
Select the first radio button to enter the latitude in sexagesimal notation
(degrees, minutes, and seconds); select the second radio button to enter the
latitude as a decimal fraction.
If the SmartServer is located south of the equator, enter a negative value
between 0 and –90. If it is located north of the equator, enter a positive
value between 0 and 90.
Longitude Enter the east-west location of the SmartServer relative to the Prime
Meridian. Select the first radio button to enter the longitude in
sexagesimal notation (degrees, minutes, and seconds); select the second
radio button to enter the longitude as a decimal fraction.
If the SmartServer is located west of the Prime Meridian, enter a negative
value between 0 and –180. If it is located is located east of the Prime
Meridian, enter a positive value between 0 and 180.
Elevation Displays the altitude of the sun calculated by the SmartServer. The
elevation is the angle between the sun and the horizon of the SmartServer.
The displayed elevation is based on the time and SmartServer position
stored in the real-time clock and astronomical position sensor,
respectively. This field is read-only.
Click Refresh to obtain the current elevation of the sun. This is useful if
you change the time or location of the SmartServer.
Azimuth Displays the azimuth of the sun calculated by the SmartServer. The
azimuth is the angle of the sun around the horizon (measured from the
north point towards the east). The displayed azimuth is based on the time
and SmartServer position stored in the real-time clock and astronomical
position sensor, respectively. This field is read-only.
Click Refresh to obtain the current azimuth of the sun. This is useful if
you change the time or location of the SmartServer.
5. Click Submit. The elevation and azimuth are stored in the nvoElevation and nvoAzimuth
SNVT_angle_degdata points. Based on these data points, the SmartServer calculates the sunrise
and sundown and stores the results in nvoSunRise and nvoSunSet SNVT_time_stamp data points.
You can then schedule events to start or end at the sunrise and sundown or a configured time
before or after. This is useful for a variety of applications such as street lighting, outdoor lighting,
sun blind, and sun shade controls.
6. You can also view the calculated sunrise and sundown times. To do this, expand the Real-Time
Clock functional block, right-click the nvoSunrise or nvoSunset data point, and then click Show
Value on the shortcut menu.