Bangalore, India based JVS Electronics Pvt Ltd offers Instantaneous and Definite Time DC Under and Over Voltage Relays.

Details:
JVS Electronic offers instantaneous/definite time DC under/over voltage relays – JRV 202/JRV 212. Applications: instantaneous/definite time under voltage/over protection DC system; and other instantaneous/definite time, under voltage/over voltage applications requiring adjustable settings.

Features: software based design; wide setting range; negligible burden; trip indication with LED; trip test facility; dust proof enclosure; and compact size. Description; the power required is drawn from the auxiliary AC supply.

The sensing DC voltage is stepped down by a resistor network. This low level voltage is fed a voltage comparator.

When this signal exceeds a preset level, the comparator output changes state and operates a relays, the positive feed back from the output to the reference of the comparator ensures sufficient hysteresis to provide a high drop-off/pick-up ratio. The time delay is achieved by R-C network and the operating time corresponds to the setting on the DIP switch.

A ´Trip Test´ push button is also provided. When the push button is pressed, the output element of the relay is energised and its contacts close to energise trip and alarm circuits.