The relay is suitable for single and three phase. auto reclosing The relay consists of five modules viz. Front fascia, power supply, two relay and status module and microcontroller module. All the modules are housed in a compact 3N Non draw-out case. Microcontroller does the sequence control and timing function. Different operating functions and time setting are selected by the DIP-Switches on the relay front fascia.
There is a watch-dog timer in the relay which continuously monitors the program, put off POWER ON indication and closes annunciation contact in case the watch dog timer elapses.
Two optically isolated inputs are provided to take the single phase or three phase protection operated contact inputs to initiate the auto reclose relay.
In addition, one permit input is given which when energized from check synchronizing or dead line charging function interlocked with the breaker status permits the auto reclose The reclose function is get blocked when the external blocking input is initiated.
The relay having two reclose timers one for single phase reclose another for three phase reclose. The both timers are selected automatically depending upon the reclose selection.
There is the common reclaim timer. It operates in series with the reclose timers. The over all reclaim time delay from relay energisation to relay reset is therefore reclaim timer setting plus reclose time.
When the reclose selector switch is in OFF mode any one of the protection operated contact input initiation condition it will energise the lockout relay and its LED indication and it blocks the reclose function.
When the external blocking input is initiated, the reclose function is blocked and it energise external blocking LED, Lockout LED and Lockout relay.
As the relay is suitable for single shot auto reclose, at the time of first reclosing if the fault persists or further fault develops within the reclaim time it will energises the lockout relay and its LED indication.Before the reclaim time elapses if the second fault occurs the relay goes to lockout.