Hi guys,Ā
These days I am usingĀ Top-conĀ Total Station. ThatĀ top-conĀ software has some thing called " Grid Factor".
I am using SLD 99 Sri Lanka coordinate system and used GPS to establish few control points at site.
My problems are Ā Ā
- Should I careĀ Grid FactorĀ when doing large scale surveying and setting out?
- What is the real idea ofĀ Grid FactorĀ ?
- Why this grid factor setting not in Sokkia instruments?
I found this information from top-con manual.
Calculation FormulaĀ
1) Elevation Factor
Elevation Factor = Ā Ā Ā RĀ Ā Ā Ā Ā Ā Ā Ā Ā Ā Ā R Ā Ā Ā : The average radius of the earth
Ā Ā Ā Ā Ā Ā Ā Ā Ā Ā Ā Ā Ā Ā R+ELEV. Ā Ā Ā Ā Ā ELEV. Ā Ā : The elevation above mean sea level
2) Scale Factor
Scale Factor : Scale Factor at the surveying station
3) Grid Factor
Grid Factor = Elevation Factor Ć Scale Factor
Distance Calculation
1) Grid Distance
HDg = HD Ć Grid Factor Ā Ā Ā Ā HDg : Grid distance Ā Ā HD : Ground distance
2) Ground Distance
Ā Ā Ā HD =Ā HDg
Ā Ā Ā Ā Ā Ā Grid FactorĀ
Welcome any idea and Thanks for helpingĀ
Replies
Please let me know how could I know the scale factor of surveying stationĀ