SI9600189A - Implementation of thermal phase breaking in a variable resistor power module - Google Patents

Abstract

Thermal disconnection and its signaling solves the problem of reliable disconnection of energy varistor module from the phase of the supply voltage, as well as outwardly signaling this disconnect that is visible from both the frontal and lateral directions. Thermal disconnection is due to the soldered solder (10) at the breaker contact (5) and because of the tensioned spring (6) which moves the housing groove (11) also the breaker guide (2). They move together with the breaker bus (2) breaker contact (5) that is separated from the varistor contact (9) and a plug (4) that jumps into a convex transparent window (8) at module housing (1), thereby signaling the trip.

Description

THERMAL PHASE DISCONNECTOR ON THE VARISTOR

The invention belongs to the field of electrical engineering, namely to the field of regulation of overvoltage protection or overcurrents in a low-voltage power grid.

For overvoltage and current protection in the power grid and installations, metal oxide varistors are mostly used, which, due to overvoltage influences, destroy the electrical characteristics, which means a drop in insulation resistance, nominal voltages and a weakening of the nonlinear coefficient. The deterioration of the electrical characteristics of the varistor results in an increase in sustained current through the varistor, thereby heating the varistor and its surroundings, which can result in damage to electrical installations, devices, and the fire of the surroundings.

The technical problem is to perform thermal disconnection on the varistor, so that it acts in case of deterioration of the electrical characteristic of the varistor, and to achieve automatic disconnection of the phase part of the varistor from the mains voltage.

The status of disconnection of the phase part of the varistor from the mains voltage must be signaled externally, since after the thermal disconnection the electrical installations and devices are over-voltage protected. Such a varistor and thermal disconnect assembly must be replaced with a new one as soon as possible.

The solution according to the invention is a specially designed housing that provides the varistor with a solid support and a sliding thermal disconnect, consisting of a circuit breaker bus, circuit breaker contact, springs and a signaling plug.

When the varistor is heated due to the deterioration of its electrical characteristic, the contact of the circuit breaker is disconnected from the varistor, due to the tense spring under thermal disconnection, it slides across the groove of the housing and causes the phase contact of the varistor to disconnect from the supply voltage. At the same time, the plug, which is red in color, is inserted into a transparent convex window on the module body and externally signals the disconnected status of the circuit breaker.

According to the invention, two problems are solved:

1. Reliable operation of thermal disconnection on the varistor and thus a sufficient separation distance of the circuit breaker

2. Good disconnect signaling, which is detectable not only from the front of the module but also from the lateral directions of the module.

Foreign manufacturers such as SuperSafe, Obo Bettermann, Dehn & Sohne and others have different thermal disconnect solutions and its signaling. The trip is solved by thermal fuses or circuit breakers that do not always provide a safe separation distance for the circuit breaker during operation.

The invention is shown in the figures:

FIG. 1: Layout of thermal disconnection in the module

FIG. 2: Disconnect signal on module housing in spatial view

The thermal disconnection is shown in Fig. 1 and is made through a plastic housing 1, which is divided into a chamber in which a varistor 3 and a groove 11 are inserted, after which the thermal disconnector slides.

The thermal circuit breaker consists of a plastic guide 2 which extends tapered into the plug 4, which is used to signal the trip and is red.

The breaker contact 5, the spring 6 and the cable 7 are attached to the bus 2, which is used for the flexible electrical connection of the thermal breaker to the phase contact of the power supply 12.

In the stationary state, contact 5 is soldered with a low-temperature (145 ° C) solder 10 to the varistor 9 contact.

The electrical connection is made after the phase contact of the power supply 12, through the cable 7 to the contact 5 and through the solder 10 to the contact of the varistor 9 and through the varistor 3 to the output contact.

Thermal disconnection works by heating the varistor 3, transferring the temperature to the varistor 9 contact and melting the solder 10.

The melting of the solder 10 releases the connection of the contact 5 and the varistor contact 9. The taut spring 6 under the guide 2 causes its movement through the groove 11 to the upper wall of the housing 1. The movement of the contact 5 is achieved due to its firm connection to the guide 2 and the flexible connection with the cable 7. By moving contact 5, mechanical and electrical disconnection of contact 5 from varistor 9 contact is achieved.

Due to the tapered extension of the guide 2 into the plug 4, it is ensured that the plug 4 is inserted into the convex transparent window 8, thus signaling the trip.

Figure 2 shows the thermal disconnect signaling performed by the plug 4, which is red in color, in a transparent window 8 projecting from the housing 1.

Claims (4)

1. The thermal phase breaker on the varistor is made in the housing together with the varistor, and is characterized therewith. that it is inserted into the chamber (77) of the housing (7), which is used for positioning and moving only in the vertical direction. Thermal circuit breaker according to claim 1, characterized in that a contact (5) is formed on the circuit breaker bus (2) made of electrically non-conductive material and is made of electrically conductive material and, that at one end (73) it has a punctured braid (7), which is also punctured to the output contact (72), and at the other end (14) the contact (5) is soldered to the varistor (9) by a solder (70). Thermal circuit breaker according to the preceding claims, characterized in that a spring (6) is inserted in the lower part (75) which pushes it vertically. Thermal circuit breaker according to the preceding claims, characterized in that the circuit breaker guide (2) extends into a tapered extension - plug (4), which can be inserted into the convex window (8) on the housing (7) due to movement of the guide (2). .