Inverse Time Over Voltage Relay Block VDG11

Type : VDG11

Features and technical specifications:

1. Self-powered, no need for separate auxiliary supply.
2. Identical time/voltage characteristic on all taps.
3. Frequency compensated.
4. Simple construction, easily accessible.
5. Dust-tight drawout case and tropicalised finish.

Application :-

Inverse time over-voltage protection of ac circuits, capacitors and machines such as generators and
synchronous motors.

This Inverse time over-voltage protection relay block is easily insert in your schematic diagram and connect as you like way.                                                                                                                                                                                       The voltage  input to the relay is fed to the coil of an induction disc element through an input transformer. The
required voltage setting is selected by means of taps on the primary of the input transformer.The  secondary of the transformer is also connected to an auxiliary unit through the disc element contact. Hence there is no necessity to
provide a separate auxiliary supply. The output of the auxiliary unit may be wired to trip the breaker. The induction disc element is heavily damped, frequency compensated and has adjustable inverse time/ voltage characteristics. The relay disc is so shaped that as it rotates, the driving torque increases and offsets the changing restraining torque of the control spring. This feature combined with the high torque of the relay ensures good contact pressure even at voltages near pick-up. Damping of the disc movement is by a removable high retentivity permanent magnet. The unique method of winding the operating coil ensures that the time/ voltage characteristics are identical on each of the seven voltage taps.The relay operating time can be adjusted by movement of the disc backstop, controlled by rotating a knurled moulded disc at the base of the graduated time multiplier scale.