Astronomical Clock - Siemens SIMATIC RTU3030C Operating Instructions Manual

Programming
5.6 Blocks for time functions
5.6.9

Astronomical clock

Requirement
Requirement for a precise calculation is the time-of-day synchronization of the RTU.
Function
With this function, the output is set to 1, when the system time of the RTU is between the
time of sunrise and sunset.
The RTU calculates these times based on its current system time (including daylight
saving/standard time) and its geographical position.
If you select "System location" for "Position", the RTU uses the geographical position
configured on the "System" page in the WBM. With the setting "Manual" you can set position
values for the block.
Parameters
Parameters
Input parameters
En
Function parameters
Position
Latitude
Longitude
Output parameters
Output
218
Range of values Description
Enable parameter, see section Often used parameters
(Page 198).
Option for setting the geographic coordinates:
System location
•
•
Manual
•
•
-90 .. 0 .. +90 Latitude
Enter the value for the latitude if you have selected the
setting "Manual" for the "Position".
Entry only as a number: Degrees with 4 decimal places
North = positive, south = negative
-180 .. 0 .. +180 Longitude
Enter the value for the longitude if you have selected the
setting "Manual" for the "Position".
Entry only as a number: Degrees with 4 decimal places
East = positive, west = negative
Tag in which the value calculated by the block is output.
Digital output / bit
•
Switching:
memory
•
•
Manual: Specification by entering the coordinates in
the input fields for "Latitude" nd "Longitude".
System location: Use of the coordinates configured
for the RTU.
At sunrise: 1
At sunset: 0
Operating Instructions, 09/2017, C79000-G8976-C382-04
RTU3030C