How do I set a Station Height?

Why does station height matter?

If you are working with a layout or measuring application that requires obtaining any height information, setting up a station height is likely a best practice. Here is where a station height is most commonly needed:

1. Measuring and Recording points which will be used in a future design projects (such as stair or walkway railings, sidewalk locations, playground equipment locations, etc.)
2. Finding the slope variability between points
3. Performing cut and fill applications when moving dirt

There are many reasons heights are needed with layout - and luckily, setting heights for your total station is very easy to do within HCL.

What does Station Height actually mean?

Have you ever wondered what the crosshair below the power button was referring to on the total station? It is referring to the center location of the telescope of your head unit.

When you are setting a station height, you are telling your total station the height coordinate that the center of the head unit is located. 

As a basic example, imagine that your total station is sitting on a tripod that is established on the ground on your jobsite. The ground your total station is sitting on also has a 0m elevation height value. If you were to properly measure the ground as the 0m height benchmark, your total station "station height" value would likely be between 1-2m.

Now that the total station knows how high (or low) it is in relation to your benchmark height, it will be able to measure in points and objects with the related height values as well.

If you measure in your benchmark height properly, the recorded heights you make while you perform your measurements should also be accurate.

Indicate the Targeting Method you will use

Make sure that before you start measuring anything, that you know how you will be measuring it. Remember that the "target" icon at the top of the screen can be selected to change the target method you wish to use. 

Establish the Height of Rod, if necessary

If you are using a prism on a prism rod (like the POA 20 or POA 25), make sure you also have the correct height of rod established.

This often gets overlooked when a prism rod is being used. This number is a measurement from the center of the prism to the bottom of your prism pole, also known as your "height of rod." 

When working with heights, this is needed because when a prism rod is in use, the tool is technically measuring to the prism toward the top of the rod, rather than to the point the bottom of the prism rod is resting on. Having the "height of rod" value will remind the tool to subtract the height of rod to calculate the actual height value of the point you are measuring.

Step 1: Turn on "Heights" in General Settings

If you do not indicate you intend to work with heights in the general settings, the height values will be disabled. Please make sure this is on for you to set a height for your total station.

Step 2: Open the Related Stationing Application

Remember that establishing a height for the total station to reference is part of the stationing applications. Setting a station height is part of helping the station understand it's location on a jobsite.

If you have not already stationed the tool by one of the stationing options open to you, you will need to do so. Setting a station height will automatically appear during this stationing process.

If you have already stationed the tool, but would like to make sure the station height is correct, then you can open the  "Edit station Height" icon on the home screen to reset or edit it.

Step 3: Indicate the Method in Which you Intend to Set the Station Height

There are 3 methods to establish a station height. While it is most common that you will likely use the "set manual height" option, as that allows you to simply measure the height for the tool based on any visible jobsite benchmark, we will go through all options here.

Note - the "absolute height" option is less so much about setting the station height, but more so about how you would like to read the heights while working with the total station. Please disregard this option for setting your station height - a separate article is available to discuss how to use this section when needed.

Option 1: Set Benchmark Height

Use this option if you intend to set a station height based off a specific point (of any type) in your point file from the project.

Simply tap on the open box that allows you to select the point you would like to use as your benchmark point. You can select any point you need from your list.

Then, notice how that point's height value appears automatically in the "point height" section of your screen:

Now the tool is ready to measure to that point you guide it to and calculate the "station height." Take note that the "reflector height," or, "height of rod" is now automatically loaded from the value you indicated at the top. You can adjust it here again if you need to.

Measure your point by pressing the measure button, followed by the green check mark, and notice that your new station height will be displayed on the new stationing icon in your point list.

Remember that your station height represents the height location of the crosshairs beneath the PLT's power button in relation to your measured benchmark height, as explained above.

Option 2: Set Manual Height

This option will likely be the most common option you use to set the station height. Simply type in the benchmark height value you are measuring, remembering to adjust the height of rod, if necessary:

Then, press the measure button, followed by the green check mark.

Your new station height value will appear relative to the benchmark height you used.

Option 3: Station Height

If you are able to somehow manually measure the station height on your jobsite, you can type in your manual measurement here. This is typically done when you know the benchmark height of the ground itself, and can measure from the ground to the center cross hair of the PLT to manually calculate the height. Make sure to press the green check mark when done.

While this is not common to do with the PLT, if it is convenient for your workflow, it is available for you to do.