CZ27965U1 - Measuring and feeding isolator - Google Patents

Description

Technical field

The technical solution relates to an insulator enabling connection and powering of measuring and communication devices on the high voltage level, especially separately installed.

Background Art

MV measuring and communication devices use separate measuring transformers or capacitive dividers or resistive dividers to measure. The power supply is either from the LV network or, in the case of separate installations from the measuring transformer, as a power transformer. With the current tendency to reduce the power of measuring and communication devices, the use of the above-mentioned set on the MV level is structurally demanding, expensive and less reliable.

It is an object of the present invention to provide a simple device which replaces known assemblies intended for measurement at the MV level.

The essence of the technical solution

Said object solves a measuring and power insulator of cylindrical shape through which a measuring branch passes through at least one measuring resistor and a supply line in which at least one power capacitor is connected, the two branches being connected at one end of the insulator to the MV contact designated to connect to a high voltage conductor. At the other end of the insulator, the measuring branch is connected to the measuring contact and the supply branch to the supply contact. In doing so, the two branches are surrounded by a cylindrical screening grid connected to the ground contact at the other end of the insulating tube.

In order that the stress on the insulation between the branches and the grid over the length of the branches is approximately the same, the measuring and supply lines are connected to the MV contact with each other and diverging from the MV contact.

At least two resistors can be connected in series in the measuring line and at least two capacitors are connected in series in the power line.

Clarifying the drawing image

The invention will be further elucidated with reference to the drawing, in which FIG. 1 shows the location of the components and contacts of the measuring and power insulator.

Examples of technical solutions

The measuring and power insulator of FIG. 1 is intended for measuring and supplying measuring and communication devices at locations even without available power from the low-voltage level and in places spatially confined with an increased possibility of external interference. At the same time, it is characterized by its simple construction and reliable function.

In the embodiment of FIG. 1, the components thereof comprise a high voltage terminal 1 and a ground terminal 5 disposed in the axis of the cylindrical insulator, an axially symmetrical shielding grid 4, a measuring resistor 2 as part of the measurement branch, and a power capacitor 3 as part of the power supply line. In this case, the extension of the voltage gradient in the insulating material 6 between the two branches is provided by the extension 12 of the high voltage outlet I. The screening grid 4 shields the influence of the external fields on the accuracy of the measurement.

If necessary, a series of multiple resistances can be used instead of one measuring resistor 2.

The high-voltage outlet 11 is provided on the outside with an external contact 11 and an extension 12 on its inner side, with a high-voltage end 21 connected to a measuring condenser by its high-voltage end 21 and a power capacitor connected to its other side. 3. This creates a distance between the two connections. The measuring resistor 2 and the capacitor 3 are located inside the screen 4, which is connected to the ground terminal 5 by its contact 41, which is provided with an earth contact 51 on the outside. The low voltage end 22 of the measuring resistor 2 has a measuring contact 23 on its outside and the low voltage end 32 of the power capacitor 3 is provided with a power contact 33 on its outer side. The difference between the contact pitch 23 and 33 and the width of the extension 12 causes divergence of the measuring and supplying branches, thereby achieving a variable thickness of the insulating material 6 between the branches with the measuring resistor 2, resp. branches with power capacitor 3 and shielding grid 4.

ίο Multiple power capacitors may be used instead of one power capacitor 3 if necessary.

Claims (3)

PROTECTION REQUIREMENTS 1. Measuring and supplying insulator of cylindrical shape, characterized by passing through a measuring branch in which at least one measuring resistor ( 2), and the power branch in which it is 15 at least one supply capacitor (3) is connected, both branches being connected at one end of the insulator to a high voltage contact (11), at the other end of the insulator the measuring branch is connected to the measuring contact (23) and a power contact (33), the two branches being surrounded by a cylindrical screen (4) connected to the ground contact (51) at the other end of the insulator. Measurement and supply insulator according to claim 1, characterized in that the measurement and supply line are connected to the HV contact (11) at a distance from each other and diverg from the MV contact (11). Measuring and supply insulator according to claim 1 or 2, characterized in that at least two measuring resistors (2) are connected in series in the measuring string. Measuring and supply insulator according to claims 1 to 3, characterized in that at least two supply capacitors (3) are connected in series in the supply line.