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Avionics Fire Detection Solved by CPI Thermal Switches

CPI Thermal Switches are solving fire and heat detection applications for a large variety of Military and Non-Military Applications.  Typically used for these applications is our Rod & Tube line of Thermal switches owing to several important operational characteristics. For one, these switches are certified to RTCA DO-160C which represents the harshest conditions you are likely to encounter in an avionics application. The list of specific testing area’s includes the following:

  • Vibration – 10hz to 2000hz over multiple hours and 3 different axis.
  • Humidity – 95% relative humidity at 65C over ten 8 hour cycles
  • Sand & Dust – 99% Silicon Dioxide <.045mm diameter, under high temperature, humidity and wind, six sides exposed.
  • Salt Spray – 5% Salt Solution with atomized fallout rate of 0.5 to 3.0 ml/hour per 80 cm2 for 50 hours
  • Temperature & Altitude – Switch energized for up to 2 hours at 85C, altitude testing to 70,000 feet.
  • Shock & Crash Safety – Sine and half sine shocks at 15G and 30G repeated up to 18 times for 11 milliseconds each.

Thermal Switches Made for The Avionics Industry

Just one of the many avionics applications CPI has been designed into include the new Diamond Aircraft DA42 L-360 used by Embry Riddle Aeronautical University as a trainer. This twin engine propeller plane from Austrian company Diamond Aircraft was chosen because it offered so many advantages over prior-generation designs. This includes an all-composite construction, state-of-the-art Garmin G1000 glass panels, and reliable Lycoming 180-horsepower engines. While each new DA42 L-360 comes equipped with an advanced glass cockpit, the ERAU fleet has been upgraded to include an Automatic Dependent Surveillance-Broadcast (ADS-B) traffic and weather system.

One other important part of the DA42 is the CPI X2003-506 thermal switch used in the engine compartment fire detection systems. “The X2003 is really made for fire detection applications,” says Pete Gagliardi, CPI’s regional sales engineer, “a slow make/break device with a set point from 0F to 1750F that is ultra reliable and accurate.”

A Look at CPI Rod & Tube Thermal Switches

The X2003 thermal switch belongs to a class of stand alone Rod & Tube style, bi-metal Thermal Switch products where contact movement is achieved via differences in the coefficients of expansion of two materials, in this case the outer tube and the inner rod. This family of switches is characterized by very rapid response time and very high temperature sensing which operate completely independently of any external control system. The switch has seen many deployments in aircraft over the years, where remote sensors and control systems are not a good or reliable option.

These thermal switches can be procured in multiple rod lengths and multiple contact configurations. They have been used in helicopter engine exhaust, plastics extrusion, aircraft brake applications, among many other demanding applications for the industrial, aerospace, and military industries.

CPI Thermal Switches Fly Safely in Aircraft Applications.

In addition to fire detection, CPI thermals have a long history of success in military and non-military avionics applications.  Here are just a few:

Especially popular for fire and heat detection on aircraft are our rod and tube thermals because of their ability to operate with set points up to 1750F.

Snapstat thermal switches boast a set point range: 0°F-300°F (-17.8°C-148°C) and are perfect for panel or pcb mounting. They have also been qualified in a hermetically sealed option that has dielectric resistance up to 5000 VAC.

For more information call a CPI engineer today.

Make The "Switch" to CPI

If your momentary switch application demands high performance, we think you should demand CPI. Please call us today to speak with our engineering team about your needs.

(973) 887-9400