JPH0145692B2 - - Google Patents

Abstract

1. Circuit breaker (1) which has a totalising current transformer (3) accessible from the outside and fitted in the housing (5) of the switch (1), for passing through the lines (6) to be monitored, and terminals (2) on the housing (5), which are connected to further protective components, in particular those of a line circuit breaker, characterised in that the totalising current transformer (3) in the housing (5) is arranged in the introduction direction of the lines directly in front of the terminals (2), in such a way that their line introduction aperture (7) is accessible only through an aperture (4) in the totalising current transformer.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a zero-phase current transformer that is accessible from the outside and has a through hole through which a wire to be monitored passes, and other protective components, particularly an overcurrent protection switch, that are arranged in a case. The present invention relates to a protective switch including a protective component and a connecting terminal connected thereto.

In such protective switches, the zero-phase current transformer is fitted into the free ends of the connecting wires between the connecting terminals, or is mounted on a metal bridge. The free ends of such metal bridges form the connections of the aforementioned cross-connecting wires. Thereby, it is intended that the zero-phase current transformer of the earth leakage trip device be connected in a simple and easily removable manner at the wire inlet. This easily removable connection also facilitates repairs.

However, with such protective switchgears that have a zero-phase current transformer that is accessible from the outside, the installer generally has to be careful that the winding direction is correct and that the connecting wires are routed correctly. It has the disadvantage that it cannot be used. Correct routing of the wires, as done in the manufacturing plant, is thus a prerequisite for obtaining the expected protective function.
If such work is performed by an amateur, there is a risk that the connections will not be made correctly and that the expected protection function will not be obtained.

The object of the invention is to improve a protective switch of the type mentioned at the outset in such a way that the introduction of the wires necessarily takes place correctly.

This purpose, according to the invention, is such that the zero-phase current transformer is arranged in the case immediately in front of the connecting terminal, and the wire inlet of the connecting terminal is monitored only through the through-hole of the zero-phase current transformer. This is achieved by means of a protective switch which is located in a position where electric wires can be introduced.
If the wires are connected to the connection terminals in such a protective switch, it is simultaneously ensured that the wires are connected in the correct direction and in the correct geometrical position through the zero-phase current transformer in the prescribed manner. Moreover,
Conventionally, the general advantage of the external accessibility of zero-phase current transformers is that it is particularly easy to construct a protection switch that combines an overcurrent protection switch and an earth leakage protection switch. You can get it exactly as expected.

It is further advantageous for the through-hole of the zero-phase current transformer to taper in a funnel-shaped manner towards the wire inlet of the connection terminal. This makes production particularly simple and easy.

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a protection switch that is a combination of an earth leakage protection switch and an overcurrent protection switch. This protective switch 1 has two or more connection terminals 2
It is equipped with A zero-phase current transformer 3 is arranged in the case 5 immediately in front of the connection terminal 2. The electric wire 6 is connected to the wire inlet 7 of the connecting terminal 2 through the through hole 4 of the zero-phase current transformer 3.
It can only be introduced through That is, the wire inlet 7 is located at a position where the wire can be connected only through the through hole 4 at the center of the zero-phase current transformer 3. In other words, the electric wires 6 can be uniformly introduced through the zero-phase current transformer 3. Therefore, it is also impossible to wind the wire around a zero-phase current transformer many times.

The through hole 4 of the zero-phase current transformer 3 connects to the connecting terminal 2 in a funnel shape.
If the wires are tapered toward the wire inlet 7, the wires can be connected even more easily. In particular, the dimensions of the through-hole 4 through which the wires pass can be matched to the cross-sectional dimensions of the wires to be connected. In this case, it is also possible to leave some play to facilitate the connection of the electric wires.
This allows the geometrical position of the wire to be determined particularly well.

FIG. 2 also shows an earth leakage and overcurrent combined protection switch having connection terminals for four electric wires 6. The central opening may be designed as a single oval opening. On the opposite side of the protective switch from the connection terminal, a connection terminal of a normal form is arranged for connecting an electric wire leading to the load to be protected.

[Brief explanation of drawings]

FIG. 1 is a side view of a protection switch that is a combination of an earth leakage protection switch and an overcurrent protection switch, and the connection terminals are shown in cross-section in the area of a zero-phase current transformer. FIG. 2 is a plan view of an example of a composite protective switch having connection terminals for four electric wires, with a part of the case cut away in the area of the zero-phase current transformer. 1...Protective switch, 2...Connection terminal, 3...Zero-phase current transformer, 4...Through hole, 5...Case, 6...
Electric wire, 7...Electric wire introduction port.

Claims (1)

[Claims] 1. A zero-phase current transformer that is accessible from the outside and has a through hole through which monitored electric wires pass, and is connected to other protective components disposed in the case, particularly protective components of an overcurrent protection switch. In a protective switch including a connecting terminal, a zero-phase current transformer is disposed in the case immediately in front of the connecting terminal, and the wire inlet of the connecting terminal A protective switch characterized in that it is located in a position where the electric wire can be introduced only through the mouth. 2. The protective switch according to claim 1, wherein the through hole of the zero-phase current transformer tapers in a funnel shape toward the wire inlet of the connection terminal.