Theodolite T30 and other models - what are these devices?
What is the essence of the theodolite's work and what requirements should it meet? The principle of measuring an angle is to compare the object under study with a point whose coordinates are known to be known. In the observation hole there is a scale, on it and these values are checked. Various theodolite brands have some differences in the device and organization of scales, but in general the principle is the same for all.
The models of this device are divided into three large classes: high-precision, precise and technical. The latter are the least accurate, the device T30 and its modifications just refers this device to this class. But this classification does not allow such devices not to meet the basic requirements of standardization, which we briefly describe in order not to go into details of the structure:
- the perpendicularity of the axis of rotation of the aliad to the axis of its horizontal circle must be observed;
- one thread from a common mesh should occupy a vertical plane;
- the perpendicularity of the axis of the telescope and the sighting axis is necessary;The
- of the aliad and the axis of rotation of the telescope must also be at an angle of 90 degrees.
Theodolite stamps - how to understand what we are buying?
If you have ever participated in the choice of a theodolite, you probably saw in the specification of the model a lot of incomprehensible numbers and letters, but they all matter. Directly the letter "T" in the title informs us that we are dealing with a theodolite. The figure after this letter indicates the accuracy class, namely, the error in minutes: T1 - high-precision( error to ± 1 "), T2-5 - accurate, T15-60 - technical.
Theodolites T5 and T30 are popular on modern construction sites, depending on the scale and budget of the project as a whole.
The number before the letter "T" indicates the generation of the device: the higher the digit, the newer the generation. There are also letters after T, they can tell us about the additional functions of the model under consideration( M, P, K, A, E).Most often, the functions K - compensator, P - direct vision( has a special device of the telescope), E - electronic devices are in high demand.
Now let's try to decipher, for example, how to read the theodolite 4T30P .This is a 4-generation device, a technical accuracy class with an error of 30 minutes, is equipped with a direct vision telescope. If this point is clarified, you should refer directly to the characteristics of the various devices.
Theodolite 4T30P is compared with the range of other offers
Model T30 from its subsequent modifications( including 4T30P) differs in the counting system. If in the very first generation the dashed principle of the microscope is used, then in the second generation and higher( 2T30, 3T, 4T) this system will be of the scale type. Such a system of a microscope is equipped with the theodolite 2T5K , which belongs to the exact class.
Comparing the third generation of collimator devices, for example, the theodolite 3T5KP and 3T2KP, it can be noted that all of their indicators will indeed be the same, except for the error in measuring the angle. The difference in the figure after the letter "T" was discussed above, in the first case it will be an average of 5 minutes, in this theodolite 3T2KP will be mistaken for only 2 minutes maximum.
The accuracy of the theodolites will affect the complexity of their verification, but at the same time create a sense of perfection of calculations already on the construction site. In addition to explicit parameters, which are indicated in the device labeling, with the growth of the device generation some more parameters, for example, increase, are growing. At Т30 the increase is considered equal х18, and here already at 2Т30 it will be equal х20.