A survey unit is one basic unit of measure; in whatever system you are using. If you use a metric system, a unit is one meter. If you use an imperial system, a unit is one foot, chain, rod or pole. Regardless of the unit you use, the entire survey consists of one unit (every coordinate is feet, meters, chains, etc.).
The formulas used in TPC to compute coordinates, central angles, stations, etc. are “unitless” - they work the same whether the survey units are imperial, metric or some unique user defined value. When TPC computes the elevation of a foresight, it knows the instrument height, target height and control point elevation are so many units.
It’s up to the user to keep the units consistent. If your coordinates are in feet, the values used to compute coordinates should be in feet.
Each time you start a new survey, TPC uses the default units for the new survey. To set the default units, choose Tools | Program Settings | Units. This won’t affect the current survey, but will affect any new surveys.
TPC reports area based on the current survey units. If the survey is in meters, area is reported as square meters and hectares. If the survey is in imperial units, the area is reported as square feet and acres.
The survey units affect how Drawing View reports sizes and scales. If the survey is in meters, TPC reports text sizes in millimeters. Scale is a ratio where 1:1000 means that one cm on the drawing is equal to 1000 cm on the ground.
If the survey is in imperial units, TPC reports text sizes in inches and scale as feet to the inch, where 40 means that one inch on the drawing is equal to 40 feet on the ground.
You can change the units the program works with for the current survey and also for any new surveys you create.
File New Command
File Open Command
File Save Command
File Save As Command
Working with Survey Files
Searching for Points
Using Scale Factors
Changing Units Using Coordinate Conversion
Working with Areas
Setting the Default Direction
Starting a Survey
Choosing a Survey Grid
Personal, Premium, Professional