CN209358231U - a surge protector - Google Patents

Abstract

The utility model discloses a surge protector, one end of the first piezoresistor is connected with the live wire of the commercial power, the other end of the first piezoresistor is connected with the neutral wire of the commercial power, the second piezoresistor is connected with the first The varistors are connected in parallel, one end of the first varistor is connected to one end of the first fuse, the other end of the first fuse is connected to one end of the normally open terminal of the relay, and the other end of the normally open terminal of the relay is connected to one end of the choke coil , the other end of the choke coil is connected to one end of the second fuse, the other end of the second fuse is connected to one end of the relay coil, the other end of the relay coil is connected to the neutral line, the normally open terminal of the relay is connected in parallel with the manual switch, and the load One end is connected to the other end of the choke coil, and the other end of the load is connected to the neutral line; the advantage is that the normally open terminal of the relay is connected in parallel with the manual switch to form a self-locking, ensuring that even if the first fuse blows in the event of a surge, it can be connected again The main circuit can also be powered off to protect the load.

Description

a surge protector

technical field

The utility model relates to the technical field of electronic equipment, in particular to a surge protector.

Background technique

The surge protector, also known as a lightning protector, is an electronic device that provides safety protection for electronic equipment, instruments, communication lines, etc. The surge protector is used to damage the device, mainly reflected in the fact that once a surge occurs, in most cases it will lead to damage to the surge protector, so frequent inspections are required to prevent the surge after the surge protector is damaged. , The impact of electronic devices. At the same time, the surge protector is used with the fuse to prevent excessive surge current and protect the electrical equipment. In the actual use process, the fuse may not be blown in time or be turned on after being blown. In this case, a surge will cause irreparable damage to the electrical equipment.

Contents of the invention

The technical problem to be solved by the utility model is to provide a simple and practical surge protector which can ensure that the circuit of the electrical equipment is disconnected when a surge occurs.

The technical solution adopted by the utility model to solve the above technical problems is: a surge protector, including a first varistor, a second varistor, a manual switch, a relay, a choke coil, a first fuse and a second fuse , one end of the first varistor is connected to the live wire of the mains, the other end of the first varistor is connected to the neutral line of the mains, and the second varistor is connected to the first A piezoresistor is connected in parallel, one end of the first piezoresistor is connected to one end of the first fuse, and the other end of the first fuse is connected to one end of the normally open terminal of the relay, so The other end of the normally open terminal of the relay is connected to one end of the choke coil, the other end of the choke coil is connected to one end of the second fuse, and the other end of the second fuse is It is connected to one end of the relay coil, the other end of the relay coil is connected to the neutral line, the normally open terminal of the relay is connected in parallel with the manual switch, and one end of the load is connected to the choke The other end of the coil is connected, and the other end of the load is connected to the neutral line.

Preferably, both the first varistor and the second varistor are made of zinc oxide.

Preferably, the relay is an AC solid state relay, and the normally open terminal is closed when the relay works normally.

Preferably, the manual switch is a push switch, which is turned on when the manual switch is pressed, and turned off after the manual switch rebounds.

Preferably, the first varistor, the second varistor, the manual switch, the relay, the choke coil, the first fuse and the second Both fuses are fixedly installed in the casing.

Preferably, the housing is made of plastic material.

Compared with the prior art, the utility has the advantage that the normally open terminal of the relay is connected in parallel with the manual switch to form a self-locking, which ensures that the power can be cut off even if the first fuse is blown and then connected to the main circuit when a surge occurs. Protective effect on the load; at the same time, there is a second fuse in series on the relay coil, which can protect the relay and limit the inrush current when the main circuit is connected. If the actual current exceeds the fusing current, the second fuse will be blown, and at the same time The normally open terminal of the relay is disconnected, so that the main circuit is disconnected, which further protects the load. Since the relay adopts a solid-state relay, the solid-state relay has a smaller volume and a more sensitive response, which makes the surge protector smaller and more reliable.

Description of drawings

Fig. 1 is the installation position schematic diagram of the present utility model;

Fig. 2 is a schematic diagram of the circuit connection of the utility model.

Detailed ways

The utility model is described in further detail below in conjunction with the accompanying drawings.

As shown in the accompanying drawings, a surge protector includes a first varistor F1, a second varistor F2, a manual switch SW, a relay, a choke coil L3, a first fuse L1 and a second fuse L2. One end of the first piezoresistor F1 is connected to the live line of the commercial power, the other end of the first piezoresistor F1 is connected to the neutral line of the commercial power, and the second piezoresistor F2 is connected to the The first varistor phase F1 is connected in parallel, one end of the first varistor F1 is connected to one end of the first fuse L1, and the other end of the first fuse L1 is connected to the normally open terminal of the relay One end of K is connected, the other end of the normally open terminal K of the relay is connected with one end of the choke coil L3, and the other end of the choke coil L3 is connected with one end of the second fuse L2 , the other end of the second fuse L2 is connected to one end of the relay coil KA, the other end of the relay coil KA is connected to the zero line, and the normally open terminal K of the relay is connected to the manual switch SW is connected in parallel, one end of the load is connected to the other end of the choke coil L3, and the other end of the load is connected to the neutral line.

Both the first piezoresistor F1 and the second piezoresistor F2 are made of zinc oxide.

The relay is an AC solid state relay, and the normally open terminal is closed when the relay is working normally.

The manual switch SW is a push switch, which is turned on when the manual switch SW is pressed, and disconnected after the manual switch rebounds.

As shown in Figure 2, the first piezoresistor F1, the second piezoresistor F2, the manual switch SW, the relay, the choke coil L3, the Both the first fuse L1 and the second fuse L2 are fixedly installed in the casing 1 made of plastic material.

The working process of the utility model: after the power supply is connected, press the manual switch SW to conduct the main loop formed between the power supply, the first fuse L1, the choke coil L3 and the load, and at the same time, the relay coil KA is energized to make the relay normally open Terminal K is closed and self-locking. When the manual switch SW is released, the main circuit is still conducting; when a surge occurs, the voltage across the two ends of the main circuit increases. When the actual current passing through the first fuse L1 exceeds the fusing current of the first fuse L1, the first fuse L1 will be blown. At this time, the relay coil KA is powered off, the normally open terminal K of the relay returns to the disconnected state, and the main circuit is powered off. The first fuse L1 continues to conduct due to a fault and the main circuit is still disconnected, thereby achieving the function of protecting the load; when the actual current passing through the second fuse L2 exceeds the fusing current of the second fuse L2, the second fuse L2 will be blown, and the relay Coil KA is de-energized so that the normally open terminal K of the relay returns to the disconnected state, and the main circuit is powered off. Even if the second fuse L2 continues to conduct due to a fault, the main circuit is still disconnected, thereby achieving the function of protecting the load.

When the voltage due to the surge is added to the first varistor F1 and the second varistor F2, the resistance values of the first varistor F1 and the second varistor F2 will be greatly reduced, making the surge The current directly flows back to the neutral line through the first piezoresistor F1 and the second piezoresistor F2, thereby protecting the electrical components behind the first piezoresistor F1 and the second piezoresistor F2.

Therefore, it can be seen from the above that once a surge phenomenon occurs, the voltage generated by the surge will reduce the resistance values of the first varistor F1 and the second varistor F2, so that a large current flows from the first varistor F1 and the second varistor Sensitive resistor F2 passes through; when the main circuit current rises due to surge voltage, the existence of the first fuse L1, the second fuse L2 and the relay can effectively ensure that the main circuit is disconnected, thereby protecting the load.

Claims (6)

1. a kind of Surge Protector, it is characterised in that including the first varistor, the second varistor, manual switch, relay, Choke coil, the first fuse and the second fuse, described one end of the first varistor is connected with the firewire of alternating current, described The other end of first varistor is connected with the zero curve of alternating current, second varistor and the first varistor phase Parallel connection, one end of first varistor are connected with one end of first fuse, first fuse The other end is connected with one end of the relay normally open terminal, and the other end and described of the relay normally open terminal are gripped One end of stream circle is connected, and the other end connection of the choke coil is connected with one end of second fuse, and described the The other end of two fuses is connected with one end of the relay coil, the other end and the zero curve phase of the relay coil Even, the relay normally open terminal is in parallel with the manual switch, the other end of the choke coil and the one of load End is connected, and the other end of the load is connected with zero curve.

2. a kind of Surge Protector as described in claim 1, which is characterized in that first varistor and second pressure-sensitive Resistance is made of zinc oxide material.

3. a kind of Surge Protector as described in claim 1, which is characterized in that the relay is alternating current solid-state relay Device, when relay work, normally open end is closed.

4. a kind of Surge Protector as described in claim 1, which is characterized in that the manual switch is push switch, when Manual switch is connected after pressing, is disconnected after manual switch rebound.

5. a kind of Surge Protector as described in claim 1, which is characterized in that first varistor, described the Two varistors, the manual switch, the relay, the choke coil, first fuse and described Second fuse is fixedly mounted in shell.

6. a kind of Surge Protector as claimed in claim 5, which is characterized in that the shell is made of plastic material.