Methods of Production of Deflecting Force

Methods of Production of Deflecting Force Points : Methods of Production of Deflecting Force The indication of any instrument is determined by the combined effect of the deflecting torque and the control torque. The value of the deflecting torque must depend causes the instrument movement to rotate from its zero, or unelected position. The control must act in the opposite sense to the deflecting torque, arid the movement will take up a equilibrium position when the two torques are equal in magnitude. The electrical effects utilized for the production of the deflecting torque in carious instruments include:
(a) Magnetic effects
(b) Heating effects
(c) Chemical effects
(d) Electrostatic effects
(e) Electromagnetic induction effects

The control torque may be produced by spiral springs, occasionally by gravity, or, in the case of instruments with a suspended movement, by the strip or bifilar suspension. A damping torque may also be used if the movement is required to take up its equilibrium position reasonably quickly and without excessive oscillation. It is essential that any damping torque shall not influence the steady deflection produced by a given deflecting torque; it must always act in a direction opposite to the movement of the moving system and must increases with the angular velocity of the system, so that its effect is greatest when the rotation is rapid and zero when the system is at rest.