What does the compensator do in an automatic level?
The compensator of an automatic level uses gravity to suspend or balance a portion of the instrument optics. In this way, the optical path of light through the instrument is compensated for the vertical axis error before reaching the user’s eye.
Do automatic levels have compensators?
The automatic level has a compensator mechanism that uses a combination of fixed prisms or mirrors and a moving prism suspended on a pendulum to give a horizontal reference. When correctly set up the compensator will ensure that the ray of light through the centre of the reticule is exactly horizontal.
What is a compensator in a level?
Adjust differences in levels, for example on lifting devices with several suction cups. There is then less demand for exact positioning of vacuum handling device. Level compensators will also provides a certain degree of shock and vibration absorption. Read more.
What are the parts of auto level?
Parts of an Automatic Laser Level. The basic setup of an automatic level consists of the telescope, the circular level, three leveling screws, and a compensator.
How accurate is an automatic level?
An automatic level with 18X magnification can give readings accu- rate to 1⁄16 inch in 100 feet. A conven- tional level with the same magnifica- tion has an accuracy of about 1⁄4 inch in 100 feet. Also, to ensure accurate readings with a conventional level, the operator must check it frequently for proper adjustment.
How do I know if my crosshair readers are correct?
Hold the rod on top of stake “A” and take rod reading “a.” Then hold the rod on stake “B” and take rod reading “b.” If the instrument is exactly halfway between stakes “A” and “B,” the difference in rod readings “a” and “b” is the true elevation difference between stakes “A” and “B” regardless of the inclination of the …
What is the difference between dumpy level and auto level?
In the dumpy level, to level the bubble, one has to keep the bubble parallel to two leveling screws and then right angle to the third screw. In the auto level, the bubble can be adjusted from any side and any angle with any 3 screws available. The line of sight is manually adjusted in the dumpy level.
How does an automatic optical level work?
An automatic level, self-levelling level, or builder’s auto level includes an internal compensator mechanism (a swinging prism) that, when set close to level, automatically removes any remaining variation. This reduces the need to set the instrument base truly level, as with a dumpy level.
What is the automatic level?
A dumpy level, builder’s auto level, leveling instrument, or automatic level is an optical instrument used to establish or verify points in the same horizontal plane. It is used in surveying and building with a vertical staff to measure height differences and to transfer, measure and set heights.
How do you check auto level?
Checking Auto Level Accuracy
- Set up instrument in an area that is as level as possible and which is about 220 feet long.
- Take a reading on each rod with the instrument (or mark each piece of strapping where the cross-hair is sighted).
- Move transit to another spot on the line and take readings and mark both rods again.
How do you center bubbles in auto level?
Rotate the telescope through 90° so the bubble tube is aligned with the third levelling screw.
- The first two screws are level so they must not be touched.
- Using the left hand adjust the third levelling screw to centre the bubble. Again the bubble will move in the same direction as the left thumb.
How do you check auto level error?
What is the cause of cross hair parallax in surveying telescopes?
If we take the situation in Figure E-9 and move the eye slightly, there will be an apparent movement of the crosshairs on the object, Figure E-11. That’s because the two images do not come to focus on the back of the eye so do not move together. This shift is called parallax.
What is the use of two vertical cross hairs?
These lines are called the cross-hairs, or cross-wires. By doing so, the error of observation which might arise from an erroneous estimation of the direction is eliminated.
How do I check my auto level level?
Checking Auto Level Accuracy
- Set up instrument in an area that is as level as possible and which is about 220 feet long.
- Take a reading on each rod with the instrument (or mark each piece of strapping where the crosshair is sighted).
- Move transit to another spot on the line and take readings and mark both rods again.
How many types of auto levels are there?
two types
There are fundamentally two types of automatic levels. First, the optical one whose distinguishing feature is self-leveling i.e., the instruments gets approximately leveled by means of a circular spirit level and then it maintains a horizontal line of sight of its own.
How do you check auto level instrument error?
How do you adjust auto level?
- An Auto Level is a level with a compensator.
- Setup your tripod as level as possible, step on tripod legs to drive into the ground.
- Attach auto level to the tripod.
- Adjust level so bubble is centered in vial.
- Adjust recital until crosshairs are clear.
- Adjust the objective lens until object you are sighting on is clear.