I perform mostly setting control points and construction staking for my company with a new robotic total station we recently purchased a few months ago. Our sites are never much bigger than 500 feet. I have a Sokkia SX105. It is a 5" gun.
I was wondering what the maximum amount of seconds the gun could be out of level on the electronic level bubble before I should re-level and re backsight.
The maximum amount it should be out of level is the amount you originally leveled to.
Spend the 2000 to 3000 and buy a sokkia SDL30 or SDL50 the time and effort wasted chasing hundredths is not worth it.
DACasey, post: 400073, member: 12261 wrote: I was wondering what the maximum amount of seconds the gun could be out of level on the electronic level bubble before I should re-level and re backsight.
I did a test several years ago with a Trimble 5603. I set up the gun and a target a couple hundred feet away. I kept putting the gun further and further off level by turning one of the tribrach knobs, running the compensation dance those things do, and reshooting the target. I found that I could be close to 3 minutes off plumb before it significantly affected the vertical distance.
The gun has a digital self analysis routine to index the level.
Mark Mayer, post: 400096, member: 424 wrote: I did a test several years ago with a Trimble 5603. I set up the gun and a target a couple hundred feet away. I kept putting the gun further and further off level by turning one of the tribrach knobs, running the compensation dance those things do, and reshooting the target. I found that I could be close to 3 minutes off plumb before it significantly affected the vertical distance.
Yep. It's more likely to affect the centring and horizontal angle. Which the instrument can't compensate for.
squowse, post: 400162, member: 7109 wrote: Yep. It's more likely to affect the centring and horizontal angle. Which the instrument can't compensate for.
Confirming this. Hz tends to sway while Vz stays better. Cant completely rely on fancy dual axis collimators when it comes to Hz. Best solution is to make sure your tripod is firm and do regular hz checks to backsight. Usually uneven tripod warming causes hz to sway off, especially with non wood tripods and asphalt. Theres no fixed amount how much your electronic vial can be off because it wont tell you how much your instrument has rotated or went off from the original centerpoint into which you stationed in the first place. It only tells the plumbness. This rately is a concern when you orientate from a long distance target and perform your survey task on close distances like under 30 meters or something.
Anyway, check backsight before and after work and you are fine. For example 10mm off at a 100m translates to 1mm error to tasks performed to 10m and so on.
i sometimes run into that problem where i will set up the total station do a compensator calibration and tracker calibration before i layout anchor bolts. ill start laying out points around the job site and about an hour in or so ill notice that my level is off significally on one axis usually its like 0 1'30" trunion and 0 0' 20" sighting. i only do construction staking for large buildings and warehouses. i run a trimble s6 on trimax tripod and use seco eclipse -40mm offset backsight prisms on tribrachs and a mini prism on a rod for bolt layout and building line layout. for vertical i use trimble dini level
Grads&Meters, post: 400211, member: 12264 wrote: Confirming this. Hz tends to sway while Vz stays better. Cant completely rely on fancy dual axis collimators when it comes to Hz. Best solution is to make sure your tripod is firm and do regular hz checks to backsight. Usually uneven tripod warming causes hz to sway off, especially with non wood tripods and asphalt. Theres no fixed amount how much your electronic vial can be off because it wont tell you how much your instrument has rotated or went off from the original centerpoint into which you stationed in the first place. It only tells the plumbness. This rately is a concern when you orientate from a long distance target and perform your survey task on close distances like under 30 meters or something.
Anyway, check backsight before and after work and you are fine. For example 10mm off at a 100m translates to 1mm error to tasks performed to 10m and so on.
Unless the centring has changed 10mm as well!
I checked that few years ago and find that even if instrument goes a bit out of level then Hz angle stays 'ok'. You are making more trouble be trying relevel, then you must shoot back sight again.
When compensators hit their limit it'll stop shooting if your settings are that way. They say that the compensators will, we'll compensate all the way until it cuts out, they say...
I level to >3", check it before every Traverse set and every 15-20 minutes depending on conditions.
Fu3l3r, post: 400269, member: 11864 wrote: i sometimes run into that problem where i will set up the total station do a compensator calibration and tracker calibration before i layout anchor bolts. ill start laying out points around the job site and about an hour in or so ill notice that my level is off significally on one axis usually its like 0 1'30" trunion and 0 0' 20" sighting. i only do construction staking for large buildings and warehouses. i run a trimble s6 on trimax tripod and use seco eclipse -40mm offset backsight prisms on tribrachs and a mini prism on a rod for bolt layout and building line layout. for vertical i use trimble dini level
We use the Sokkia -40mm trav kits, on tight work they are leaps ahead of a -30.