Meggitt Sensing Systems recently announced the introduction of TEDS (transducer electronic data sheet) capabilities into its Endevco model 7290D series, allowing it to be used within larger channel count applications. The series belongs to an accurate, VC (variable capacitance) accelerometer family and offers good thermal stability, reliability and performance within flight test, engine testing and other harsh temperature testing environments.
It comes in five models measuring from 2 to 100g, and incorporates a VC sensing element with gas damping and internal over-range stops, allowing the sensor to tolerate shock and acceleration loads of up to 10,000g, with 2.5% total accuracy. The series also features non-linearity, including hysteresis of 0.2% for ranges from 2 to 50g. A custom signal conditioner has been integrated into each device, enabling it to accept input voltages from 8 to 30V with a high level, low impedance output. The ±2.25V differential output is DC coupled at a bias of around 2.5V. In order to maintain stringent thermal characteristics and high accuracy, a custom ASIC provides programmable temperature compensation achieved through five-point linear fit algorithm for both thermal sensitivity and thermal zero shifts. Units are integrally temperature compensated from -55 to +125°C to ensure temperature accuracy over the full military range. TEDScapabilities, while conforming to IEEE 1451.4, facilitate onboard storage of serial number and calibration data for easier test setups with reduced errors. The units are available with an optional triaxial mounting block, the 7990. Recommended accessories for use with the 7290D series include the model 136 three-channel signal conditioner; the model 4430A bridge transducer signal conditioner; or the model 4990A Oasis multi-rack based signal conditioning system.
