California Surveyors Forums

Does anybody know what is the range of the circular level in order to affect the measurement accuracy?
I have a Trimble 5603, I took it in for checking of the circular level accuracy versus the internal graphic level. When the bulb is perfectly centered, the graphic level on data collector is off around 1 minute on both directions. I was told by the repair tech that the base unit has been damaged which causes the difference in both levels. He told me deviation of more than 2 minutes will cause significant difference in measurement. I wanted to make sure this is true.

Not sure I fully understand your questions.
Most tribrachs have a 10 minute bubble.
The internal leveling on the 5603 is more accurate than the circular bubble.
Easy to check by rotating instrument 180 - level reading shouldn't change more than a few seconds.
The circular bubble on the tribrach is easy to adjust.
Yes, 2 minutes of mis-level does cause significant errors in horizontal & vertical angles.
Not sure what is meant by, "told by the repair tech that the base unit has been damaged which causes the difference in both levels".
Good luck.

Stan

Yes, 2 minutes of mis-level does cause significant errors in horizontal & vertical angles.

Don't the H&V compensators take care of that?

Stan, The repair guys said that both levels are OK, I think he checked the tribrach's level separately. He said the only reason why the 2 levels don't match is that the instrument is dropped and the base unit is bent (I don't know how). I know that the instrument is not dropped. He says he tested the gun and everything is OK, just the 2 levels don't match. i have tried the 180 rotation, the readings change is, sometimes near a minute.