According to the development of the existing solar insecticidal lamp, and the analysis of the status quo, large electronic engineers developed a way to use large capacity of self recovery fuse (PPTC) the resistance of the rapidly changing characteristics in the application of solar insecticidal lamp, increase and improve the solar insecticidal lamp over-current protection ability, through the current limiting test results, it was proved that the application design scheme can limit short circuit current, quickly and effectively protect the solar insecticidal lamp. The scheme has good application prospect.

Solar insecticidal lamp's role is to use a variety of ways at the same time who ensnared pests, pest traps in variety, quantity is big, can reduce the amount of pests ovum, at the same time also can protect the natural enemies of the pest, delay the onset of pest resistance, harmless to human and animal. And the solar energy kill lamp USES low cost, mobile convenience. To reduce the pollution of the earth's environment and maintain ecological balance, and provides a new choice, as vegetables, fruit trees, rice, forest, tea, cotton diseases and insect pests such as large number, drug frequently crops provides strong comprehensive physical treatment method, the pest control brought considerable ecological benefit, economic benefit and social benefit, has good practical promotion prospects, for the production of pollution-free, high quality of agricultural products, ecological protection and the development of green food opens up broad prospects.

Currently, there are four main functions of solar energy insecticide lamps, including light control, rain control, time control and voltage protection. Solar insecticidal lamp is a long-term work in the field, not only to the test of a bad experience or sunshine, wind and rain, plus some such as handling, installation or improper use of any other reason, it is easy to trap lamp short circuit, damage or breakage. Due to trap lamp is installed on the outside, very easy because of the effect of artificial or natural factors, trap lamp damage, if once appear, trap lamp damage, broken, at this point in the output of the control panel form a short circuit, causing the power switch control panel device burned, cause the damage of the control panel, then through the control panel to produce a very large current discharge battery, the battery, solar panel, control panel to cause permanent damage to the chain is a chain reaction. As a result of the existing solar insecticidal lamp did not possess the function of over-current protection, once appear, trap lamp short circuit (light damage, broken, etc.), will produce a very large current, control circuit and the burning of or damage to the battery, there are even some unsafe hidden trouble. It will bring unnecessary loss and safety hazard to users, and also bring many after-sales service fees to the manufacturers of the solar insecticide lamp.

1. Application principles and methods:

The PPTC is made of polymer polymer under high pressure, high temperature and vulcanization reaction, and after adding conductive particle material, it is processed by special process. Under normal temperature, normal working current through the PPTC thermistor inside, the combination of polymer and conductive particles density together to form crystal structure, the PPTC thermistor in the low resistance molecular state. When the recovery fuse On both ends of a short circuit or destructive large current, the series in the circuit loop self recovery fuse consumed power P = I squared R began to increase, according to the square of the current value increases, since at this time restore the fuse moment produces a lot of heat, make the PPTC internal polymer temperature rising rapidly, causing swelling, from crystalline to colloidal body at the same time, the conductive molecular chain began to fracture, thereby blocking the pathway, which is formed by the conductive particles within the PPTC resistance level KK Ω numerical at this time. Effective limiting short circuit current or destructive large current through self - recovery fuse, circuit circuit is in disconnection state. At this time, the PPTC is in high temperature and high resistance state.

After the fault current to exclude, PPTC polymer switch internal temperature of the material is reduced, polymer crystallization again, conductive particles began to conduction, the whole circuit is back to normal work, achieve the purpose of protecting solar insecticidal lamp.

2. Experimental data:

3. Application effect:

Through experiments show: the recovery fuse used in solar insecticidal circuit, when the trap lamp damage or a short circuit, PPTC for solar insecticidal lamp control circuit have very good protection effect, but also on the control panel, battery and solar panels are played a protective role, make solar insecticidal lamp has been effectively improve on the function, extend the service life of the solar insecticidal lamp, a few (dollars) at the lowest cost price, increases the solar insecticidal lamp over-current protection function, but also reduces the maintenance cost of solar insecticidal lamp, increase the reliability of solar insecticidal lamp, and security.

4. Conclusion:

This paper presents an application method of self - restoration fuse.

It can effectively increase and improve the performance of overcurrent protection by restoring the flow protector in series self-restoring fuse in the circuit.

The experiment proves that the solution proposed in this paper can solve the overcurrent protection of solar insecticide lamp and has good application prospect. More self - restoring fuse products in huizhou big rong electronic technology co. LTD. www.rpptc.com