The 6200 Series hermetically sealed switch is ideal for high temperature applications or anywhere extremely severe environmental conditions are encountered. Most commonly used on commercial and military aircraft, these switches can also be found in some space applications. Originally designed and developed for use on Mach 2 supersonic aircraft, the switch is currently being used in high temperature valves, thrust reversers and other severe environment applications.
The 6200 Series switches are highly resistant to vibration, shock and other environmental conditions typical of aerospace applications. The corrosion resistant metal and glass sealed enclosure is accomplished by using a heat treated stainless steel housing and a glass metal header. The HSI wobble diaphragm is an integral part of the housing, not a separate piece welded or brazed in place therefore the mechanical life is significantly longer than life at rated load. The glass to metal header uses materials rated to 600°F. In addition, the glass has excellent dielectric and insulation resistance, particularly important at high temperatures which degrade insulation qualities. True hermetic sealing integrity is maintained per Category 5 of MIL-PRF-8805 i.e. 1 x 10-8 atm cc/sec.
In high temperature low current operation the slightest contamination can generate film on the contacts. Since the low current cannot penetrate even the thinnest film, the result is an intermittent signal. HSI technology solves the contamination problem and prevents failure. Switches are assembled and sealed in our class 10,000 clean room environment. All metal and glass components are used in this design. Cleaning and inspection operations, to prevent contamination, are performed as a regular part of the manufacturing process. The cover is heliarc welded to the glass to metal header and the housing is backfilled with inert nitrogen gas. This provides a controlled environment for the switch contacts which makes maximum electrical life possible.
The actuator design limits overtravel to acceptable limits and will withstand up to 10 lbs. of force exerted on the actuator at its operation point.
Assemblies Available
A variety of standard assemblies are available for use with Series 6200 switches including assemblies rated up to +660°F continuous operation and up to +800°F intermittent operation. HSI can also design custom assemblies and provide electrical terminations to meet specific application requirements.
Ultra High Temperature Switch
The series 6200 is also available in an ultra high temperature version. The switch incorporates an elgiloy blade and platinum contacts to withstand operating temperatures to 900°F. Note: Hermeticity may be lost when operating at 900°F. Contact HSI for complete specifications.
6200 Series Milli-amp Switch
The 6200 series is also available in a low current version. This switch is designed to operate below 5 MA at 5 VDC in temperatures as high as 600°F.