RU2290649C1 - Contact voltage and step voltage measuring arrangements - Google Patents

Abstract

FIELD: the invention refers to electro technique and electro energy and may be used at conducting tests and exploitation control of conditions of inserted arrangements of different electric installations.

SUBSTANCE: the arrangement for measuring contact voltage and step voltage is fulfilled for two feet, separately for each foot, and each of them has a metallic plate connected through electro conducting springs with contacted feet firmly fixed on a dielectric support site equipped with contacts of plug and socket units, clamps, measuring tape and belts for fastening on the operator's footwear. At that responsive contact joints are installed on the metallic plates coaxially with contacts of plug and socket units on the dielectric support site and openings creating possibility of vertical transfer of the metallic plates along the contact feet at their insertion into the ground are fulfilled and along the perimeter of the metallic plates protective casings out of dielectric material are installed .

EFFECT: expands fields of using this arrangements, reduces labor intensiveness at measuring contact voltage and step voltage and increases accuracy of measuring.

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Description

The invention relates to electrical engineering and electric power industry, can be used during testing and operational monitoring of the state of grounding devices of electrical installations and electrical safety.

Known devices for measuring touch voltage and pitch in electrical installations using metal electrodes (rods) driven into the ground (SI Kostruba "Measuring the electrical parameters of the earth and grounding devices" - M .: Energoatomizdat, 1983).

The disadvantage of such devices is the high complexity of the work of driving and removing electrodes from the ground, the installation of wires and measuring instruments.

A device for measuring touch voltage using a plate simulating the feet of a person measuring 25 * 25 cm ² on which a person is located ("Collection of teaching aids for monitoring the status of electrical equipment. Section 1. Methods for monitoring the status of grounding devices." - M .: ORGRES, 1997).

The disadvantage of this device is that it is suitable only for measuring touch voltage, requires significant labor costs for wetting the surface of the earth, laying wet cloth, copper mesh, foam rubber and boards to accommodate a person.

A device for measuring the insulation resistance of the floor [GOST R 50571.16-99 (IEC 60364-6-61-96) "Electrical installations of buildings. Part 6. Tests. Chapter 61. Acceptance tests" - M .: Gosstandart, 1999] (accepted for the prototype).

The device contains a metal plate, contact legs, terminals, wires, measuring instruments.

The disadvantage of this device is that it has a narrow scope and is unsuitable for measuring step voltage, the measurement technology is time-consuming and time-consuming.

The technical solution to the problem is to expand the scope of the device, reduce the complexity of the measurement of touch voltages and steps, increase the accuracy of measurements.

This problem is solved in that the device for measuring the voltage of touch and pitch, containing a metal plate, contact legs, terminals, wires, measuring instruments, is made for two legs, separately for each leg and each individually has a metal plate connected through electrically conductive springs to contact legs rigidly fixed on a dielectric support platform equipped with contacts of electrical connectors, a terminal, a measuring tape and straps for fixing on the operator’s shoes, while metal plate, in alignment with the contacts of electrical connectors on a dielectric support platform, installed response connectors and contacts are provided with holes which create the possibility of vertical movement of the metal plate along the contact legs with their immersion into the ground, and on the perimeter of the metal plate is mounted a protective casing of a dielectric material.

The invention is illustrated by drawings, where Fig. 1 shows a device for measuring touch voltage and pitch (for one leg), and Fig. 2 shows a measurement technology using a device: a) touch voltage to a metal structure of an electrical installation; b) step voltage in the zone of current spreading from the grounding device.

A device for measuring touch voltages and steps, for each leg separately (Fig. 1), consists of a metal plate 1, wires 2, conductive springs 3 attached to contact legs 4, rigidly fixed to a dielectric support platform 5 and equipped with terminal 6, contacts electrical connectors 7, measuring tape 8 and straps 9 for fastening to the shoe 10. On the metal plate 1 there are mating contacts of the connectors 11, openings 12 and protective covers 13. The device is equipped with measuring instruments 14.

The device operates as follows. The operator (worker), upon arrival at the upcoming measurement site, secures the device to the shoe 10 using belts 9, attaches the wires 2 to the terminals 6, measuring instruments 14, as well as to grounding devices, metal structures or other objects [Fig.2 a), b)]. On the measuring tape 8, a predetermined step width is marked, and the tape is attached to the supporting platform 5. Measuring instruments 14 are prepared for measurements.

When measuring the voltage of contact, for example, to the metal structures of the electrical installation, Fig. 2 a), the operator is positioned so that his legs are close, and the devices on each leg comprise a common area, electrically connected by wires 2.

The mass of the operator creates the necessary force on the dielectric support pads 5 and the sharply connected pointed contact legs 4. The latter are immersed in the ground and form a reliable electrical contact with it.

At the same time, metal plates 1, tightly pressed to the ground, act on the electrically conductive springs 3 connected to the contact legs 4, form a single contact system with them, and due to the presence of holes 12 in the metal plates 1, the contact legs 4 are freely immersed in the ground until until the contacts of the electrical connectors 7 and 11 are closed between themselves and thereby connect the metal plates 1 and contact legs 4 through terminal 6 and wires 2 to the measuring instruments 14.

If the ground is solid, the operator can concentrate his body weight alternately on each leg and achieve the closure of the contacts of the electrical connectors 7 and 11, or at least one of them. This ensures control over the reliability of contact with the ground.

To protect the contact legs 4, springs 3, the contacts of the electrical connectors 7 and 11 from contamination and to create a safe working environment for the operator, the metal plates 1 along their perimeter are equipped with protective covers 13 made of dielectric material. When the operator raises his leg for the next step, the springs 3 move the metal plates 1 down to their original position, the contacts of the electrical connectors 7 and 11 open and disconnect the voltage from the metal plates 1 and the contact legs 4, while the protective casing 13 is lowered together with the metal plate 1, preventing grass, dirt, and the like from penetrating into the gap between the support platform 5 and the metal plate 1

To measure the step voltage on the earth's surface, the measuring devices 14 are switched so as to measure the voltage alternately and separately on the devices of each leg within the set step width. Measuring tape 8 limits the step width and ensures the accuracy of measurements.

The operation of the devices on each leg is similar to that of measuring touch voltage.

The proposed device is also used to measure floor resistance or measure touch voltage and pitch on floors with different coatings. For this purpose, terminals 4 of conductive rubber (not shown) are put on contact legs 4 with a diameter of 39 mm [GOST R 50571.16-99 (IEC 60364-6-61-86) Electrical installations of buildings. Part 6. Tests. Chapter 61 Acceptance tests. Appendix A].

Thus, with the help of the device reduces the complexity of the work on measuring the voltage of touch and step, increases the accuracy of measurements and the safety of their implementation, expanding the scope of the device.

Claims (1)

A device for measuring touch and step voltages, comprising a metal plate, contact legs, terminals, wires, measuring instruments, characterized in that it is made for two legs, separately for each leg, and each individually has a metal plate connected via contact springs to contact legs rigidly fixed on a dielectric support platform equipped with contacts of electrical connectors, a terminal, a measuring tape and straps for fixing on the operator’s shoes, while on the metal their plates coaxially with the contacts of electrical connectors on a dielectric support platform mounted connector pins and responses are provided with holes which create the possibility of vertical movement of metal plates along the contact legs with their immersion into the ground, and on the perimeter metal plates mounted protective jacket of dielectric material.

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