Nalder Lipman Moving-iron Power Factor Meter
Nalder Lipman Moving-iron Power Factor Meters are more efficient in working as compared to electrodynamic power factor meters. These power factor meters are used on a three-phase supply. Its construction and working are very simple. So, the construction and working of this power factor meter are written below:
Its moving system holds three iron elements. These three elements carry iron cylinders. These elements are mounted on a shaft and these are separated from one another with non-magnetic distance pieces. The shaft carries the damping vanes and a pointer. These three elements are at 120 degrees to each other. Each iron element is magnetized with its individual voltage coils named B1, B2 and B3. These are connected in a star connection with the supply lines. The two parallel F1 and F2 of a single current coil is connected on a line of supply.
The whole system is free to move between the two parallel halves. These meters read the power factor directly from the supply. The phase angle φ is produced in a moving system. The deflection Θ is equal to phase angle and the pointer deflects on a scale.
This instrument is not affected by the variations in voltage and in waveforms in the power supply.
A rotating magnetic field is not produced so the moving system deflects properly.