pulsing, lock-out contact output and so on, is performed. The

binary inputs are heavily stabilized against disturbance to

prevent incorrect operations at for example dc system

capacitive discharges or DC earth faults.

The binary inputs are heavily stabilized against disturbances

to prevent incorrect operations during for example during DC

system capacitive discharges or DC earth faults.

Distance protection functionality for phase-to-phase and/or

phase-to-earth faults is available as back-up protection for

faults within the transformer and in the connected power

system.

Versatile phase, earth, positive, negative and zero sequence

overcurrent functions, which can optionally be made

directional and/or voltage controlled, provide further

alternative backup protection. Thermal overload with two timeconstants, volts per hertz, over/under voltage and over/under

frequency protection functions are also available.

A built-in disturbance and event recorder provides valuable

data to the user about status and operation for post-fault

disturbance analysis.

Breaker failure protection for each transformer breaker allows

high speed back-up tripping of surrounding breakers.

The transformer IED can also be provided with a full control

and interlocking functionality including Synchrocheck function

to allow integration of the main and/or a local back-up control.

Out of Step function is available to separate power system

sections close to electrical centre at occurring out of step.

The advanced logic capability, where user logic is prepared

with a graphical tool, allows special applications such as

automatic opening of disconnectors in multi-breaker

arrangements, closing of breaker rings, load transfer logic

and so on. The graphical configuration tool ensures simple

and fast testing and commissioning.

Serial data communication is via optical connections to

ensure immunity against disturbances.

The wide application flexibility makes this product an

excellent choice for both new installations and the

refurbishment of existing installations.