Controlling torque controls the deflection and tries to stop the pointer at its final position.But due to inertia, the pointer oscillates around its final position before coming to rest. Hence damping torque is provoded to avoid this oscillation and bring the pointer quickly to its final position.Thus the damping torque is never greater than the controlling torque. In fact it is the condition of critical damping which is sufficient to enable the pointer to rise quickly to its deflected position without overshooting.
due to reflecting torque pointer moves in one direction by due to controlling torque pointer moves in opposite direction therefore pointer oscillate in forward and backward direction.if there is no deflecting torque the device to ensure that the pointer comes to rest quickly with minimum oscillation at its correct reading position is known as damping device...
Following are the essentials of indicating instruments: 1. Operating torque, 2. Controlling torque, and 3. Damping torque. OPERATING TORQUE Operating torque is produced by making use of any of these effects: magnetic, electromagnetic induction...., it is required to move the moving system of the instrument. CONTROLLING TORQUE Controlling torque opposes the operating torque and increases with the deflection of the moving system. It ensures that the deflection of the pointer is according to the magnitude of electrical quantity being measured. If this torque were not provided, the pointer would continue to move indefinitely and the deflection shall be independent of electrical quantity being measured. It also bring the pointer back to zero when the instrument is removed from the circuit. This torque is either obtained by spring or by gravity. In spring control, one or two phosphor bronze spiral hair-springs are attached to the moving spindle. The other end are attached to the frame. In this case Tc proportional to Angle of deflection. In gravity control, a small weight is attached to the moving system in such a way that it tries to bring the pointer back to the zero position when it is deflected, due to gravity. In this casse Tc proportional to sine of the angle of deflection. DAMPING TORQUE Controlling torque controls the deflection and tries to stop the pointer at its final position where its Td = Tc But due to inertia, the pointer oscillates around its final position before coming to rest. Hence damping torque is provided to avoid this oscillation and bring the pointer quickly to its final position. Thus the damping torque is never greater than the controlling torque. In fact it is the condition of critical damping which is sufficient to enable the pointer to rise quickly to its deflected position without overshooting.
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Critical damping in the context of M25 concrete typically refers to the material's response to dynamic loading and its ability to return to equilibrium without oscillation. M25 concrete has a characteristic compressive strength of 25 MPa and is often used in structural applications. The damping ratio for concrete can vary, but for M25, it usually falls within a range of 0.02 to 0.10, indicating that while it has some energy dissipation properties, it is generally not considered highly damped. Critical damping is more relevant in dynamic analysis of structures rather than a specific property of the concrete itself.
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Controlling torque controls the deflection and tries to stop the pointer at its final position.But due to inertia, the pointer oscillates around its final position before coming to rest. Hence damping torque is provoded to avoid this oscillation and bring the pointer quickly to its final position.Thus the damping torque is never greater than the controlling torque. In fact it is the condition of critical damping which is sufficient to enable the pointer to rise quickly to its deflected position without overshooting.
Controlling torque controls the deflection and tries to stop the pointer at its final position.But due to inertia, the pointer oscillates around its final position before coming to rest. Hence damping torque is provoded to avoid this oscillation and bring the pointer quickly to its final position.Thus the damping torque is never greater than the controlling torque. In fact it is the condition of critical damping which is sufficient to enable the pointer to rise quickly to its deflected position without overshooting.
The damping ratio formula used to calculate the damping ratio of a system is given by the equation: c / (2 sqrt(m k)), where is the damping ratio, c is the damping coefficient, m is the mass of the system, and k is the spring constant.
Damping torque can be provided by: (a) air friction damping (b) fluid friction damping (c) eddy current damping. In air friction damping, a light piston moves with a very small clearance in air chamber. The piston moves against pressure of air in air chamber. In fluid friction damping, light varies are attached to spindle of moving system. The movement of spindle is suppressed due to fluid friction, Eddy current damping is one of the most efficient method of damping. It is based on the principle that whenever a sheet of conducting but non magnetic material like copper or aluminum moves in magnetic field, eddy currents are induced.
air friction ,fluid friction, eddy current
to increase the sensitivity for the same damping torque
due to reflecting torque pointer moves in one direction by due to controlling torque pointer moves in opposite direction therefore pointer oscillate in forward and backward direction.if there is no deflecting torque the device to ensure that the pointer comes to rest quickly with minimum oscillation at its correct reading position is known as damping device...
so that when damping torque=controlling torque,the pointer comes back to the zero position...i.e. the main role of controlling torque is to ensure to bring the pointer to the 0 position when deflecting torque is removed
Following are the essentials of indicating instruments: 1. Operating torque, 2. Controlling torque, and 3. Damping torque. OPERATING TORQUE Operating torque is produced by making use of any of these effects: magnetic, electromagnetic induction...., it is required to move the moving system of the instrument. CONTROLLING TORQUE Controlling torque opposes the operating torque and increases with the deflection of the moving system. It ensures that the deflection of the pointer is according to the magnitude of electrical quantity being measured. If this torque were not provided, the pointer would continue to move indefinitely and the deflection shall be independent of electrical quantity being measured. It also bring the pointer back to zero when the instrument is removed from the circuit. This torque is either obtained by spring or by gravity. In spring control, one or two phosphor bronze spiral hair-springs are attached to the moving spindle. The other end are attached to the frame. In this case Tc proportional to Angle of deflection. In gravity control, a small weight is attached to the moving system in such a way that it tries to bring the pointer back to the zero position when it is deflected, due to gravity. In this casse Tc proportional to sine of the angle of deflection. DAMPING TORQUE Controlling torque controls the deflection and tries to stop the pointer at its final position where its Td = Tc But due to inertia, the pointer oscillates around its final position before coming to rest. Hence damping torque is provided to avoid this oscillation and bring the pointer quickly to its final position. Thus the damping torque is never greater than the controlling torque. In fact it is the condition of critical damping which is sufficient to enable the pointer to rise quickly to its deflected position without overshooting.
Using a torque carbon seatpost on a bicycle can provide benefits such as increased stiffness, reduced weight, improved vibration damping, and enhanced overall performance.
Critical damping is commonly used in engineering to prevent overshooting and oscillations in dynamic systems. It is applied in shock absorbers for vehicles to ensure a smooth ride and in building structures to reduce vibrations during earthquakes. In electrical circuits, critical damping is used to suppress ringing and improve response time.