3
Operation
Theory
PCS-978 Transformer Relay
3-98
Date: 2013-01-16
transformer integrated relay, and it is generally required to repeat those signals through
high-power relays to improve the anti-inference ability of the protection.
3.9.2 Function
Mechanical protection has following functions:
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 directly or with time delay.
3.9.3 Protection Principle
Transformer relay repeats external signal through high-power relays and send them to CPU
through opto-coupler circuits. After CPU receives those signals, transformer relay will record them
as events and send tripping command with settable time delays. Because the drop out time of
mechanical input signals is usually too long, the setting [MR.t_PW_n] (n=1, 2, 3, and 4) can be set
to avoid the relay sending long-time tripping command.
3.9.4 Logic
EN
[MR.En_n]
SIG
[MR.En1]
SIG
[MR.En2]
SIG
[MR.Blk]
&
SIG
[MR.Inputn]
&
[MR.t_PW_n]
[MR.Opn]
Figure 3.9-1 Logic diagram of mechanical protection
Where:
For mechanical protection, if following three conditions are met, the protection will be enabled.
(1) Logic setting [MR.En_n] (n=1, 2, 3 or 4)
is set to “1”.
(2)
Enabling inputs [MR.En1], [50/51Pn.En2] are both set to “1”
(3)
Blocking input [MR.Blk] is set to “0”.
When the protective function block is disabled, [MR.Op1], [MR.Op2], [MR.Op3] and [MR.Op4]
signals are both reset. Default values of Inputs [MR.En1], [MR.En2] are “1” and [MR.Blk] is 0 when
those inputs are not connected to external signals or settings.
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 ...