ABB REJ603 Application Self-powered feeder protection 605 series

Application

The REJ603 is a protection relay aimed at selective short-circuit and earth-fault protection

of feeders in secondary distribution networks and for protection of transformers in utilities and industries.

The inrush current stabilization function allows the relay to be used as main protection of

distribution transformers.

The relay is powered up through current transformer if current is above energizing level of

relay, front USB power or through auxiliary supply (optional feature).

The relay offers, non-directional over current and earth-fault protection. 

The residual current for the earth-fault protection is derived from the phase currents. 

When applicable,the corebalance current transformers can be used for measuring the residual current,

especially when sensitive earth-fault protection is required.

The relay additionally offers thermal overload protection for feeders, cables and transformers.

There is optional provision of remote trip through binary input with external auxiliary power supply.

The remote trip signals like transformer trouble output (Buchholz, Oil temperature,

Winding temperature trip) or an external trip can be wired

to binary input. The remote trip function works even in CT-powered mode when auxiliary supply

is not available but enough CT current is available to power-up the relay.

Measurement

The relay continuously measures phase currents and earth current. Earth current can be

measured using external core balance current transformer or can be calculated internally.

The relay has provision to display measured three phase current and earth current in primary

and secondary terms. Additionally, relay displays status of binary input, binary output and trip

counter for over current and earth fault trip.

During service, the default view of display shows three phase current and the earth current in

secondary terms. The values measured can be accessed using on the local HMI.

Event log 

To collect sequence – of – events (SoE) information,

the relay incorporates a non-volatile memory with a capacity of storing 250 events

with associated time stamps with resolution of 1 ms.

Event log includes protection operation status, binary I/O status and relay fault code.

The event logs are stored sequentially,the most recent being first and so on.

The non-volatile memory retains its data also in case the relay temporarily loses its auxiliary supply.

The event log facilitates detailed post-fault analysis of feeder faults and disturbances.

The SoE information can be accessed locally via the user interface on the relay front panel.