Contact Resistance Characteristics of Relay Operated in the Vicinity of Silicone-Type and Non-Silicone-Type Polymeric Cured Materials at Elevated Temperatures

Abstract

Influences of vapors evaporated from a newlydeveloped acryl-based polymeric material (containing no silicone components) and conventional silicone-containing polymeric materials were evaluated with respect to their effects on contact resistance characteristics of relay contacts at an ambient temperature of 120ºC. More specifically, a commerciallyavailable mechanical relay (AgSnIn contacts) was sealed into a can with one of the two materials, and placed in a heating chamber to operate, at an operating frequency of 0.5 Hz, 40,000 break operations of an inductive DC14V-0.4A load current, an inductive DC5V-1A load current, or a resistive DC14V-1A load current. Contact resistance values were measured at every 50 operations, and compared with the results obtained in the similar operation tests conducted at an operating frequency of 1 Hz. As a result, the relays sealed with the acryl-based non-silicone-type polymeric material showed no deterioration in contact resistances, irrespective of the load conditions or operating frequencies. On the other hand, the relays sealed with the silicone-containing material showed more significant deteriorations and fluctuations of the contact resistance characteristics in the 0.5 Hz operations as compared with the cases of the 1 Hz operations.

Contact Resistance Characteristics of Relays Operated in Silicone-Vapor-Containing and Non-Silicone Atmospheres with Different Electrical Load Conditions

“…The authors have been already reported some experimental results on influences of this acryl-based non-silicone-type polymeric material on contact resistance characteristics of a mechanical relay in comparison with those with conventional silicone-containing polymeric materials at elevated ambient temperatures of, such as, 80ºC and 120ºC [9][10][11][12][13]. In this paper, results obtained up to now, including previously reported data, are summarized in order to demonstrate advantages of the acryl-based non-silicone-type polymeric material over the conventional silicone-containing materials.…”

Reliability of hermetically sealed miniature relays in silicone-rich environments

“…The presence of Silicone in the contact area has therefore to be prevented in general. Different approaches for this goal are: complete removal of silicone materials from manufacturing of the switchgear throughout the product life within the application [18]; use of adequate silicone replacements [22][23][24]; or testing and approval of each silicone material in respect of its content of volatile Silicone and contact compatibility [4]. The aim of this work is to study the capability of relay housings to act as Silicone barriers: Relays with plastic housings with different sealing ratings were put into Silicone environments.…”