Open construction (device construction)

An open construction method is called a construction method for devices when the decisive components are mechanically exposed.

For measuring instruments it has prevailed earlier, but yielded mostly the enclosed design today. Their most important advantage over the latter - where they are clad or sheathed and thus shielded from the ambient air - is the easy accessibility for adjustment , checking and any repairs. The most serious disadvantage is the strong influence of radiation, air temperature , wind and dust.

In the case of surveying instruments such as theodolite and level , the open design has changed to a closed design, primarily due to the developments by Heinrich Wild from 1920, first for the most sensitive parts such as telescope supports ( tilt axis ), focusing ( inside instead of on the focuser ) and adjustment or Clamping screws .

Switchgear for voltages of over 100 kV are usually designed in an open design (outdoor switchgear).