Ferrodynamic transducers for automatic monitoring and controlling devices

Conclusions

The ferrodynamic transducers compare favorably with differential transformer transducers;

• 1) by their better linear relationship between the output emf and the angle of rotation (displacement) of the coil, which makes it possible to correct the zero of the indicating instrument without an additional transducer and without introducing any additional errors;

• 2) by the possibility of changing continuously and without using any contacts (by means of the adjustable plunger), and over a wide range, the transducer transformation ratio (the slope of the characteristic), by means of simple adjustments;

• 3) by the possibility of obtaining characteristic curves with a parallel displacement with respect to each other;

• 4) by the small moment required for rotating the moving coil and the absence of a moment of reaction in it;

• 5) by the stability of the output voltage phase in the effective angle range of the moving coil;

• 6) by the simple linear kinematic coupling between the transducer coil and the rotating elements of the instrument;

• 7) by the possibility of using ferrodynamic transducers for adding, subtracting, multiplying and dividing circuits without any rewiring or the use of matching dividers;

• 8) by the fact that ferrodynamic transducers can fully compensate the effects of transmission lines; the easy setting of a transducer for a left-hand or right-hand rotation makes the direction of rotation of the driving mechanism immaterial.