# Remote Elevation with Total Station

Need some input on this. I will be doing some precise work soon where I will need to do remote elevation and/or vertical angle to a point where accuracy to hundredths is important. I am using a Lietz SET-3 total station in very good calibration. It’s the older heavy type of SET-3, not the cheap lightweight modern ones. I set up a test area in the yard to the amusement of the neighbors and passers by.

I climbed a utility pole and put a 16d nail hole in the pole and painted it to be visible. No trouble seeing the hole with the total station. I set a nail in the ground at the bottom of the pole close enough to get the prism pole against the pole and plumb. The utility pole looks vertical. I set out two tacked hubs roughly 50′ from the pole and approx. 40å¡ apart coming out from the pole. Horizontal distances were measured from each hub to the nail at the base of the pole. I ran levels so I knew the difference in heights from each point. I measured to the center of the prism set up on the nail at the pole and measured the height of the instrument while set up at each hub.

Test 1: Entered the height of the center of prism into the total station, shot slope distance per instructions to prism, and selected remote elevation function. (The height of instrument not needed here). Turned cross hairs upward to bottom of nail hole and got 17.61′ from first hub and 17.62′ from second hub by remote elevation method.

Test 2: Measured the height from nail at base of pole to center of prism. Recorded the vertical angle at center of prism. Recorded the vertical angle to the bottom of the nail hole. Put everything into CAD considering the elevations of points, heights of instrument, and height of prism. Determined the height from nail at base of pole to bottom of hole in pole to be 17.62′ from first hub and 17.62′ from second hub by using vertical angle method.

Remote elevation and vertical angle measurements therefore agree.

I got the extension ladder, called Mrs. Penry outside and I climbed back up the pole. She held Zero end of tape on the top of the nail and I measured 17.66′ to bottom of hole in pole. Checked several times and under full tension. I laid the tape out of flat concrete, put marks in at 0′ and 25.00′. Then measured with total station to be 25.01′ to check the tape.

So vertical distances with total station by remote elevation and vertical angle agree, but are 0.04′ lower from what I measure direct with tape.

Instrument measures to 1-second on screen and stated accuracy of 3-seconds vertical.

The specifications in the manual under Remote Elevation says: ” 1 s + every 0.5 s “. (Not sure what this translates to).Would you apply a factor knowing you need to add 0.04′ of height proportionally when at a distance of 50′ from the point?

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