A Two Step Procedure to Evaluate Contact Compatibility of Organic Materials

摘要

The formation of carbon on the contact surfaces of commercial relays by thermal decomposition of organicrnvapors emanating from various organic materials may cause an undesirable increase of the contact resistancernin the range of several Ohms.rnA two stage analysis is proposed, in order to find general rules for the influence of organic materials onrncontact reliability: The first step of investigation is to determine the molecular structure and quantity of thernemanated gases from interesting organic materials by chemical analysis. The second step is to investigate therninfluence of individual organic vapors and their combinations on contact reliability, using a speciallyrndeveloped test device.rnThe results of preliminary experiments with organic vapors showed that it is possible to determine criticalrnconcentrations causing the effect of carbon contamination within a predetermined interval of operations, whilernlower concentrations did not cause any effect.rnFor organic materials a critical temperature can be determined similarly, as far as a certain temperature of thernmaterial corresponds to a certain concentration of emanated gases.rnVarious quantitive informations about contact compatibility of various vapors and materials were gained.