Способи оцінки терміну служби контактів

Abstract

METHODS FOR EVALUATING THE SERVICE LIFE OF THE CONTACTS

A. Mrachkovskyі, V. Markova

Now widely used method of directly switching contact materials testing when using information erosive properties of contact materials obtained on the mock relays, choosing optimal in terms of efficiency and durability of the contact material, and produce a pilot batch relay and test it.

The purpose of research - analysis of the physical processes at work surfaces switching devices.

Materials and methods of research. Initial data for calculation are the parameters of the circuit - current, voltage, time constant, constructive contact system parameters -mizh relay contact gap, tightening the contact springs, the contact pressure, the Electric and Electro-contact materials parameters - current, voltage and power arc burning, erosion rates the composition of the material.

Results. The direct method provides reliable information about the lifespan. Even with wide automation tests are quite cumbersome, lengthy, and in addition to test results is difficult to directly determine the effect of individual factors on life - design, materials and other contacts.

The second approach is to test contacts to mock installations, simulating relay operation. However, the transfer test results directly to the relay contact system can not, because after selecting the contact materials using mock facilities necessary to carry out direct experimental test series relays.

Direct tests are conducted in the modes set standards. Operating load is usually different from the standard. It is recommended to determine the allowable number of cycles of inclusion-off for losing weight for the duration of service (which is quite difficult for contact of the relay because of the small size).

Conclusions

1. The calculated parameters such as time curves, energy, the amount of electric power, volume and mass erosion enable fast enough to evaluate material and design contact contact system when developing new or upgrading structures known relays, but do not do it in absolute terms of switching durability (validity).

2.Isnuyuchi methods of calculating the term of the relay contacts are suitable for the type of sphere-plane switching range at DC. Calculated methods of evaluating the validity of the second relay contacts when switching types of AC and DC are not available.

3.Development common approach to assess the estimated life of the relay contacts with the methods of calculation EDM processes contacts to asse