Meggitt Sensing Systems has introduced the Sensorex SX41800 series, a family of high-performance digital RS-485 (MODBUS) servo accelerometers. The series is designed to deliver a high-reliability output, proportional to acceleration, in support of linear acceleration and deceleration measurements within automatic rail and light rapid transit system monitoring and positioning control (ATO, ATP, and ERTMS), low-frequency (seismic) vibration measurement and structural monitoring applications.
Offered in four ranges from ±0.1 to ±1.0 g, design of the accelerometer series incorporates an inertial mass mounted onto a coil, which tends to move with respect to the housing of the accelerometer when the accelerometer is subjected to motion. Based on the galvanometric principle, movement of the coil is detected optically and transduced into an electrical signal, which then excites the coil to return the inertial mass back to its null position. The amount of excitation current required to maintain the inertial mass in its null position is in direct proportion to the applied acceleration or deceleration and is therefore the output signal source. In addition, because the damped inertial servo mechanism is fully oil immersed, the units exhibit high shock and vibration resistance with a good damping factor.
An analogue ±5V output signal is also available via one of the output pins. An integrated auto-test function allows the user to check the servo loop and most other associated functions. Sensorex SX41800 units are also CE EN 50155 railway norm and CE EN 61326 norm qualified.
For more information, visit Meggitt Sensing Systems.
Sources: Press materials received from the company and additional information gleaned from the company's website.