All relays supplied with Military Specification reference, have been subject to rigid inspection for quality conformance and a comprehensive schedule of test and acceptance requirements, in accordance to National military standard (NK-2C) and specification (i.e. Mil-PRF-39016), under the surveillance of the Italian MINISTRY of DEFENCE, D.G. TELEDIFE (previously TELECOMDIFE).
These processing techniques ensure long relay life
To ensure consistent manufacturing, all handling and processing techniques are fully controlled and documented. complete identification and traceability records are maintained All parts are inspected and cleaned prior to assembly. Flow and handling of materials is arranged to minimize excessive handling of parts and assemblies and to ensure a minimum total fabrication time from initial assembly to the final sealing process.
Complete contamination control is achieved during the manufacturing cycle of this highly reliable component. Completed header assemblies are processed through a proprietary chemical cleaning sequence which removes all types of contaminates. the open relay assembly is progressively cleaned during the fabrication. Final cleaning of the completed relay assembly, prior to sealing, is accomplished by an unique system entirely housed in a laminar flow bench. Vapor degreasing, ultrasonic agitation, spray cleaning, and the use of solvents capable of removing organic as well as inorganic soils are employed to assure the ultimate in contamination removal.
After final cleaning, the relays are transferred into a vacuum outgassing station. The vacuum system was specifically designed for this application and is fully protected against contamination with molecular sieve traps, liquid nitrogen, and water cooled optical baffles. The custom designed high temperature vacuum oven and pumping station is capable of maintaining temperature limits and gradients within ±2°C.
Optimum temperature, vacuum, and time parameters are obtained by continuous monitoring. Since relays are baked in an open stage, degassing is not restricted through a small tip-off hole, as is generally the case with other relay types, thus providing the ultimate in outgassing characteristics.
Final seal operation
At the conclusion of the degassing cycle, the open relays are passed from the vacuum oven through an interlock into an atmospheric controlled dry box. The back filling gas is continuously recirculated through an inert purification system, capable of changing the entire volume of gas within the dry box every 5 minutes. An analytical moisture analyzer controls and welder is enclosed within the dry box which hermetically seals the housing to the relay assembly.
All relays are checked for contact resistance, pull in and drop out, dielectric strength, insulation resistance, contact bounce, operate and release time, and coil resistance. Continuous monitoring of all processing equipment and methods ensures maintenance of reliable switching performance at all times. The result of the various contamination process controls is a switching device capable of operation throughout its rated environmental extremes, with consistent contact performance in the low level, minimum current, and power switching regions.