1 Introduction
PCS-978 Transformer Relay
1-12
Date: 2012-12-08
Two-stage definite-time overexcitation protection and one-stage definite-time overexcitation
alarm element are equipped.
One-stage inverse-time overexcitation protection including tripping and alarm functions is
equipped.
Overexcitation inverse-time curve is sectional linear curve, which has high adaptivity.
1.3.8 Mechanical Protection
High-power relays are adopted to improve the anti-inference ability of mechanical protection.
Mechanical protection does not maloperate if 110Vac (or 220Vac) voltage is connected to the
terminal of mechanical relay signal input by mistake.
Provide 4 mechanical signal input channels for tripping instantaneously or with time delay.
1.3.9 Temperature Protection
Being applied to protection of a transformer or a reactor.
Receiving 6 DC signals (4~20mA or 0~5V) from external temperature transducers to convert
to temperature values.
1.3.10 Impedance Protection
Two stage phase-to-phase impedance protection elements.
Two stage phase-to-earth impedance protection elements
Power swing blocking releasing function.
1.3.11 Phase Overcurrent Protection
Four-stage phase overcurrent protection with independent logic, current and time delay
settings.
Stage 1, stage 2 and stage 3 are definite-time characteristic, stage 4 can be selected as
definite-time or inverse-time characteristic. The inverse-time characteristic is selectable,
among IEC and ANSI/IEEE standard inverse-time characteristics and a user-defined
inverse-time curve.
Voltage control element can be selected to control each stage phase overcurrent protection.
Directional element can be selected to control each stage phase overcurrent protection with
three options: no direction, forward direction and reverse direction.
Second harmonic can be selected to block each stage phase overcurrent protection.
1.3.12 Ground Overcurrent Protection
Four-stage ground overcurrent protection with independent logic, current and time delay
settings.
Stage 1, stage 2 and stage 3 are definite-time characteristic, stage 4 can be selected as
Summary of Contents for PCS-978
Page 1: ...PCS 978 Transformer Relay Instruction Manual NR Electric Co Ltd ...
Page 2: ......
Page 6: ...Preface PCS 978 Transformer Relay IV Date 2013 01 16 ...
Page 10: ...Preface PCS 978 Transformer Relay VIII Date 2013 01 16 ...
Page 62: ...3 Operation Theory PCS 978 Transformer Relay 3 p Date 2013 01 16 ...
Page 250: ...4 Supervision PCS 978 Transformer Relay 4 b Date 2013 01 16 ...
Page 264: ...4 Supervision PCS 978 Transformer Relay 4 14 Date 2013 01 16 ...
Page 266: ...5 Management PCS 978 Transformer Relay 5 b Date 2013 01 16 ...
Page 272: ...5 Management PCS 978 Transformer Relay 5 6 Date 2013 01 16 ...
Page 334: ...6 Hardware Description PCS 978 Transformer Relay 6 60 Date 2013 01 16 ...
Page 370: ...8 Human Machine Interface PCS 978 Transformer Relay 8 d Date 2013 01 16 ...
Page 404: ...8 Human Machine Interface PCS 978 Transformer Relay 8 34 Date 2013 01 16 ...
Page 406: ...9 Configurable Function PCS 978 Transformer Relay 9 b Date 2013 01 16 ...
Page 446: ...10 Communication PCS 978 Transformer Relay 10 26 Date 2013 01 16 ...
Page 448: ...11 Installation PCS 978 Transformer Relay 11 b Date 2012 10 09 ...
Page 456: ...11 Installation PCS 978 Transformer Relay 11 8 Date 2012 10 09 ...
Page 458: ...12 Commissioning PCS 978 Transformer Relay 12 b Date 2012 12 07 ...
Page 468: ...12 Commissioning PCS 978 Transformer Relay 12 10 Date 2012 12 07 ...
Page 470: ...13 Maintenance PCS 978 Transformer Relay 13 b Date 2012 10 09 ...
Page 474: ...13 Maintenance PCS 978 Transformer Relay 13 4 Date 2012 10 09 ...
Page 476: ...14 Decommissioning and Disposal PCS 978 Transformer Relay 14 b Date 2012 10 09 ...
Page 478: ...14 Decommissioning and Disposal PCS 978 Transformer Relay 14 2 Date 2012 10 09 ...
Page 480: ...15 Manual Version History PCS 978 Transformer Relay 15 2 Date 2013 01 16 ...