Fail-safe position sensor uses redundancy
A new magnetostrictive Temposonics GT position sensor from MTS Sensors ensures maximum safety for all applications where a failure could have disastrous effects on safety and cost.
The redundant G-Series sensor measures critical variables by means of two or three independent, functionally identical measurement systems. They are completely independent and can be switched on individually.
Each measurement system comprises a basic sensor element, evaluation electronics with separate output signal, and supply voltage. The sensor elements are accommodated in a pressure-resistant stainless steel pipe for direct stroke measurement in hydraulic cylinders. The non-contact position magnet travels along the sensor rod, which emerges into the open piston and marks the measurement point through its wall.
Measurement validity is checked by totals formation with inverse output signal programming (4-20mA, 20-4mA, total = 24) or by difference formation (difference = 0). If variations are detected, remedial action can be taken immediately.
The Temposonics GT's measurement accuracy offers the same well-proven performance as MTS' standard sensors. Linearity is said to be better than 0.02 per cent and repeatability better than 0.001 per cent. Due to the high linearity, even very small measurement differences are identified, enabling the error tolerance to be adjusted individually and adapted to the application. The stroke length is also selectable freely within 25-1500 mm.
At critical measurement points, the Temposonics GT provides safe linear position measurement, protects against failure and ensures availability. Applications include: motor-actuated positioning at power station turbines; pitch adjustment of wind turbines or marine screw propellers; marine control systems; and flood gates.
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