Why an overheat detector?
The THERMOCOAX Bleed Air detector is designed to detect leaks in an aircraft’s pneumatic duct system by sensing the temperature of the overheat air surrounding the leaking duct. We also supply the detector to survey the AGB oil duct in the engine nacelle.
The fire dectector version is mainly dedicated to control overheat around ECC on the engine.
The NEGACOAX technology gives the location of the overheat condition, reports it to the aircraft crew's warning system. Thermocoax’s Overheat facility has been used on commercial and military platform, aircraft or helicopters, and also in military tank compartiments in case of overheat where electronics are fixed.
Description : Based on our Mineral Insulated Cable, THERMOCOAX develops these specific overheat sensors based on an insulator dopped with eutectic salt.
It detects any air leakage in the wings, pylon, APU, nacelle. In case of bleed failure, the eutectic salt melts due to the overheat when leakage heats the cable, and so the electrical insulation level drops. The alarm will stop when the leakage is stopped and means the overheat has disappeared.
Has been used on MD90, A340, Global Express and current programs for Embraer KC390, Falcon SMS.
Key parameters for overheat detector :
- MTBF: 4.4 107 F.H –MTBUR: 100.000 F.H.
- Service life: 20 years
- Flight cycles: 30 000
- Flighth: 40 000
- Fire qualified MIL F 7872 C.
- Qualification RTO DO160 / MIL - HALT
- Voltage: up to 32 volts
- Flammability as per 14 CFR Part 35
- Alternating current
- Frequency 2Khz
- Max current 100mA
- Voltage: min 1 volt rms, max 15 volt rms