4 Supervision
PCS-978 Transformer Relay
4-7
Date: 2013-01-16
When the secondary phase-to-phase voltage of VT is equal to 100V:
1) Positive sequence voltage is less than 30 V and any phase current is greater than 0.04 In.
2) Positive sequence voltage is less than 30 V and the breaker is in closed position.
3) The negative sequence voltage is greater than 8 V.
4) The 3
rd
harmonic magnitude of phase voltage is greater than 10V.
If the secondary phase-to-phase rated voltage is set to 110V, all corresponding operating voltage
will be adjusted in the same ratio.
Logic
SIG U2>8V
SIG U1<30V
10s 10s
SIG [52b]
SIG [OnLoad]
SIG [In_VT]
SIG Up_3rd>10V
≥
1
≥
1
&
[Alm_VTS]
Figure 4.3-3 Voltage pre-processing logic diagram
Where:
Up_3rd is the 3
rd
harmonic value of phase voltage.
U2 and U1 are respectively negative sequence voltage value and positive sequence current value.
[52b] is the b
inary input of auxiliary normally closed contact of a circuit breaker.
[OnLoad] is a flag indicating there is load current detected.
[In_VT] is the input signal of indicating VT in service.
[Alm_VTS] is the alarm message of VT secondary circuit abnormality.
4.3.3 Frequency Supervision
If system frequency detected is too high or low, transformer relay will send alarm signal [Alm_Freq]
instantly tor reminding users for attention. Users can configure two settings [f_High_FreqAlm] and
[f_Low_FreqAlm] in “
System Settings
” menu.
4.4 Failure and Abnormality Alarms
NOTE!
Following alarm messages and corresponding LED indicators are fixed in
equipment software. Besides, there are other programmable LED indicators configured
according to user requirement.
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 ...