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Hi all,I have my total station is equipped with a x-tilt sensor.
In some cases the zenith angles (vertical angles) change up and down.
In some cases the x-tilt sensor shows that there is a tilt on the station
not allowing the measurement to take place,
. Trying to figure out what is going on, I turned off
the x-tilt and made some test measurements in one-two face positions,
the differences were 3-4cc (in gradians 0,0003-0,0004).
I activated the tilt-sensor and performed again some test measurements,
the differences between one and two face positions are about 2c
(in gradians 0,0200). So here are some questions to all of the
1. Have any of you found such a problem with total stations?
2. Is the difference of 2c between face one-two with the x-tilt sensor
enabled justified at all?
Thank you for your time.
ps. I am mostly trying to figure out if I can use some measurements
that were taken with that total station, and the x-tilt sensor on.
This Content Originally Published by a land surveyor to Land Surveyors United Network
It looks like the instrument is out of adjustment. Therefore I would not trust any measurements until the instrument has been adjusted.
My first question is when was the last time this total station was calibrated in the shop? It is quite possible that your x-tilt sensor is out of alignment with your main instrument level. This would result in your x-tilt being right at its edge of tolerance while the main levels appear to be right on. Hence any settling, no matter how minor, would put the x-tilt out of tolerance.
As to your "does it matter" question, if all you are doing is collecting topo shots, you are most likely ok as long as your distances are under 100 to 130 meters ( 300 to 400 feet). If you are doing transverse, boundary or staking work then you are not ok, get it shop calibrated.
Hope this helps,
Fairly recently, so i don't understand how it all of a sudden has that problem.
I have been making some tests and noticed this. The average of face one and face two zenith angles with x-tilt on, gives basically the same value as face one zenith without x-tilt on. That probably means that the false tilt correction gets eliminated by the average of face one and face two measurements. That gets me thinking that maybe the measured zenith angles can be corrected by adding half of the difference between face one-two zenith angle, since i performed some face one and face two measurements during that job for traverse purposes.
Well, all distances were bellow 12 meters, but that doesn't really matter if the zenith angles are very small for example 20gons, since a difference of 6c can mean a difference in 1cm.
Take it back to the shop. They may not have tightened a set screw or the like. Also, if happened suddenly it could be the result of the instrument be struck or shocked. Are you the only person that uses this instrument? Any number of things could have knocked it about. So I'd make another trip to the shop with it.
The instrument just needs a regular service and calibration procedure to be done and if this does not solve then the compensator has to be checked.