DE29619365U1 - Remaining service life display, for displaying the status of switching contacts on switching devices - Google Patents

Description

Klöckner-Moeller GmbH -1- 0 537 GM

28.10.96

Remaining service life indicator to display the status of switching contacts in switching devices.

The invention relates to a remaining life indicator according to the preamble of claim 1.

In switching devices such as contactors, relays, motor protection switches and the like, contact erosion occurs as a result of switching arcs, which determines the service life of the switching device depending on the frequency and intensity.

Without special displays, it is not possible to see the remaining service life of the switching device. However, such a display can be very helpful because the switching device can then be replaced in time before it becomes inoperable.

It is already known from DE-AS 10 92 101 that

Contact piece burn-off mechanically by an indicator plunger

These solutions are relatively inaccurate and also very expensive. '""'

Furthermore, it is known from DE 37 14 802 A1 to arrange a light guide with a light receiver in such a way that it is destroyed when the contact wears down, so that a change in the measured signal occurs at the light receiver. This solution is also not economically viable, especially for small devices.

Other known solutions, as described in more detail in FR 2 452 175, EP 0 258 090, EP 0 414 657 or EP 0 441 472, have relatively complex sensors and evaluation units and cannot be arranged in the smallest of spaces.

Klöckner-Moeller GmbH -2- 0 537 GM

28.10.96

The object of the invention is therefore to create a cost-effective remaining service life indicator according to the preamble of claim 1, which can be used universally.

The object of the invention is achieved by the characterizing features of claim 1, while particularly advantageous developments of the invention are characterized in the subclaims.

The invention, further refinements and improvements of the invention and further advantages will be described and explained in more detail with reference to the drawing, in which two embodiments are shown.

It shows:

Fig. 1 is a representation of a first embodiment of the remaining life indicator and

Fig. 2 is a representation of a second embodiment of the remaining life indicator.

A first embodiment is shown in principle in Fig. 1. The switchgear housing 1 has a viewing window 2 with a UV filter. Behind the viewing window 2 there is a photochemical element 3 for visual control, which changes its color permanently when it is exposed to UV radiation, e.g. in the red range.

The radiation generated by the switching arcs hits the radiation-sensitive side 4 of the photochemical element 3, which is protected against the arc fault gases by a protective window 5. The protective window is UV-permeable and is arranged on the wall 6 of the arc chamber 5. The protective window is arranged in such a way that the radiation generated by the switching arc hits the photochemical element 3.

Klöckner-Moeller GmbH -3- 0 537 GM

28.10.96

The photochemical element 3 consists of photochemical materials suitable for integration and display.

Figure 2 shows a second embodiment in which a light guide 7 is arranged. The light guide 7 is arranged with the front side of its light guide end butting against the protective window. The other end is arranged on a UV film (photochemical element 3). This arrangement has the advantage that the arrangement of the UV film and the viewing window 2 is independent of the arrangement of the arc chamber 5.

• * &idiag;

Xlöckner-Moeller GmbH -4- 0 537 GM

28.10.96

List of reference symbols

Switchgear housing 1

Viewing window 2

radiation-sensitive page 4

photochemical element 3

Arc chamber 5

Wall 6

Light guide 7

Protective window 8

Claims (6)

Klöckner-Moeller GmbH • * · · ·• · ·•# · ·• · · · · · ·» ·. * ·> · · ·• · ··*·> * ··· · .> · · ·>· ·· ··O537 GM-5-28.10.96 Protection claims 1. Remaining service life indicator for indicating the state of arcs in switching contacts of switching devices in which switching arcs can occur, characterized in that the remaining service life indicator consists of a photochemical element (3) exposed to the radiation of the switching arcs occurring in the switching contact space or in the arc chamber (5), which changes its optical properties with the frequency and intensity of the radiation occurring on it and consists of photochemical materials which are suitable for integration and display. 2. Remaining life indicator according to claim 1, characterized in that the photochemical element (3) is a UV radiation-sensitive film which changes its color when exposed to radiation. 3. Remaining service life indicator according to claim 1 or 2, characterized in that the photochemical element is arranged behind a viewing window (2) integrated in a switchgear housing for visual inspection, which has a filtering effect for the wavelength at which the change in the optical properties occurs. 4. Remaining life indicator according to one of the preceding claims, characterized in that the viewing window (2) is a UV filter. 5. Remaining life indicator according to one of the preceding claims, characterized in that a light- or radiation-permeable protective window (8) is present between the contact space or arc chamber (5) and the photochemical element (3). Klöckner-Moeller GmbH O 537 GM 28.10.96 6. Remaining life indicator according to one of the preceding claims, characterized in that a light guide (7) is present between the contact space, i, arc chamber (5) and the photochemical element (3).