high impedance differential relay block 7VH83

Type : 7VH83

Features and technical specifications:

1.  Integral CT shorting relay
2.  Robust solid state design
3.  Inrush stabilisation through filtering
4.  Fast operating time
5. Simple voltage setting
6.  Integral bus wire supervision                                                                                                                                                                                                                                                                                                                                  This high impedance differential relay block is easily insert in your schematic diagram and connect as you like way.                                                                                                                                                                 Applications :- The 7VH83 relay is designed for fast and selective differential protection based on the high impedance circulating current principle. It is used for the protection of machine stator windings, busbars and transformer and reactor windings against phase to phase and phase to earth short circuits.                                                                                                                                                                                                                   The withdrawable module is housed in a 7XP2020 metal case suitable for flush mounting. The plug connector at the rear of the case has one screw and one snap on terminal for each connection point. The plugconnector is marked with a coordinated system depending on the mounting location,The 7VH83 relay is a three pole sensitive current relay. The AC input impedance of the relay is regulated by a constant current circuit that is independent of the voltage setting.The relay setting voltage pick-up value is set by means of DIL
   switches located on the front of the relay module. The voltage setting is determined by adding the base value
   to the sum of the selected setting switch positions.The CT shorting relay is designed to short circuit the CT bus wires instantaneously removing the high voltage across the relay CT input.The input from the CT’s is
   galvanically isolated from the static operating circuit. The AC measured current is band pass filtered and
   rectified to a proportional dc voltage. This voltage is monitored by switching circuits controlled by zener
   diodes. When the dc voltage exceeds the set value, the solid state amplifiers operate the command output relays, the LED indication and a latched CT shorting relay.