Background Image
Table of Contents Table of Contents
Previous Page  240 / 248 Next Page
Information
Show Menu
Previous Page 240 / 248 Next Page
Page Background

Current transformer with

Rogowski toroid or air-core CT

10

,W LV PDGH XS RI D FRLO ZLWKRXW DQ LURQ IUDPH WKURXJK ZKLFK D SRZHU EXVEDU UXQV 7KH

RXWSXW YROWDJH DW WKH FRLO WHUPLQDOV LV SURSRUWLRQDO WR WKH FXUUHQW ÀRZLQJ WKURXJK WKH

EDU 7KH UHVXOW LV D FXUUHQW WUDQVIRUPHU &7 ZLWK D YROWDJH RXWSXW 7KH DGYDQWDJH LV

WKDW LW QHYHU VDWXUDWHV ZKDWHYHU WKH SULPDU\ FXUUHQW DQG WKXV HQDEOHV PHDVXUHPHQW

RI KLJK FXUUHQWV 7KH RXWSXW LV KRZHYHU D YHU\ ORZ FXUUHQW WKDW LV WRR ORZ WR VXSSO\ WKH

PHDVXUHPHQW HOHFWURQLFV

)RU 0LFURORJLF 5RJRZVNL &7V PHDVXUH WKH FXUUHQW DQG D VHFRQG &7 ZLWK DQ LURQ

FRUH SURYLGHV WKH HOHFWULFDO VXSSO\

Demand current, demand

power and peak values

A-21

$YHUDJH RI WKH LQVWDQWDQHRXV FXUUHQW RU SRZHU YDOXHV RYHU DQ DGMXVWDEOH ¿[HG RU

VOLGLQJ WLPH LQWHUYDO 7KH KLJKHVW YDOXH REVHUYHG RYHU WKH WLPH LQWHUYDO LV WKH SHDN

YDOXH 7KH WLPH LQWHUYDO UXQV IURP WKH ODVW UHVHW

Instantaneous current

A-21

7UXH UPV YDOXH RI WKH FXUUHQW PHDVXUHG E\ WKH FXUUHQW WUDQVIRUPHUV RYHU D VOLGLQJ

WLPH LQWHUYDO $YDLODEOH RQ 0LFURORJLF $ RU (

Instantaneous voltage

A-21

7UXH UPV YDOXH RI WKH YROWDJH PHDVXUHG E\ WKH YROWDJH VHQVRUV RYHU D VOLGLQJ WLPH

LQWHUYDO $YDLODEOH RQ 0LFURORJLF $ RU (

Maximeters/minimeters

A-20

0LFURORJLF DQG $ RU ( FDQ UHFRUG WKH PLQLPXP DQG PD[LPXP YDOXHV RI HOHFWULFDO

SDUDPHWHUV RYHU VHW WLPH SHULRGV

Overvoltage category

29& 2YHUYROWDJH FDWHJRU\

,(&

$QQH[ +

A-32

6WDQGDUG ,(&

VWLSXODWHV WKDW LW LV XS WR WKH XVHU WR VHOHFW D PHDVXUHPHQW

GHYLFH ZLWK D VXI¿FLHQW RYHUYROWDJH FDWHJRU\ GHSHQGLQJ RQ WKH QHWZRUN YROWDJH DQG

WKH WUDQVLHQW RYHUYROWDJHV OLNHO\ WR RFFXU

)RXU RYHUYROWDJH FDWHJRULHV GH¿QH WKH ¿HOG RI XVH IRU D GHYLFH

&DW , 'HYLFHV VXSSOLHG E\ D 6(/9 LVRODWLQJ WUDQVIRUPHU RU D EDWWHU\

b

&DW ,, 5HVLGHQWLDO GLVWULEXWLRQ KDQGKHOG RU ODERUDWRU\ WRROV DQG GHYLFHV

b

FRQQHFWHG WR VWDQGDUGLVHG 3 HDUWK HOHFWULFDO RXWOHWV 9

&DW ,,, ,QGXVWULDO GLVWULEXWLRQ ¿[HG GLVWULEXWLRQ FLUFXLWV LQ EXLOGLQJV PDLQ ORZ

b

YROWDJH VZLWFKERDUGV ULVLQJ PDLQV HOHYDWRUV HWF

&DW ,9 8WLOLW\ VXEVWDWLRQV RYHUKHDG OLQHV FHUWDLQ LQGXVWULDO HTXLSPHQW

b

Percent load

A-23

3HUFHQWDJH RI FXUUHQW ÀRZLQJ WKURXJK WKH FLUFXLW EUHDNHU ZLWK UHVSHFW WR LWV UDWHG

FXUUHQW 0LFURORJLF ( 0 RIIHUV WKLV LQIRUPDWLRQ DQG FDQ VXP LW RYHU WKH WRWDO

RSHUDWLQJ WLPH WR SURYLGH WKH ORDG SUR¿OH IRU WKH IROORZLQJ UDQJHV WR

WR

WR DQG

u

Phase sequence

A-23

7KH RUGHU LQ ZKLFK WKH SKDVHV DUH FRQQHFWHG / / / RU / / / GHWHUPLQHV

WKH GLUHFWLRQ RI URWDWLRQ IRU WKUHH SKDVH DV\QFKURQRXV PRWRUV 0LFURORJLF ( 0 WULS

XQLWV SURYLGH WKLV LQIRUPDWLRQ

Power and energy metering

(consumption)

A-21

7KH GLJLWDO HOHFWURQLFV LQ 0LFURORJLF ( FDOFXODWH WKH LQVWDQWDQHRXV SRZHU OHYHOV

DSSDUHQW 6 LQ N9$ DFWLYH 3 LQ N: DQG 4 LQ N9 DQG LQWHJUDWH RYHU D WLPH LQWHUYDO

WR GHWHUPLQH WKH FRUUHVSRQGLQJ HQHUJLHV N9$K N:K NYDUK &DOFXODWLRQV DUH IRU

HDFK SKDVH DQG IRU WKH WRWDO

Time-stamped histories

A-23

0LFURORJLF WULS XQLWV VWRUH LQIRUPDWLRQ RQ HYHQWV H J DODUPV DQG WKHLU FDXVH WKDW DUH

WLPH VWDPSHG WR ZLWKLQ D PLOOLVHFRQG

P

rotection.......................................................................................................

Ground-fault protection G (Ig)

A-19

3URWHFWLRQ IXQFWLRQ VSHFL¿F WR HOHFWURQLF FLUFXLW EUHDNHUV V\PEROLVHG E\ * *URXQG

7KLV SURWHFWLRQ FDQ FDOFXODWH KLJK WKUHVKROG UHVLGXDO HDUWK OHDNDJH FXUUHQWV LQ WKH

RUGHU RI WHQV RI $PSHUHV RQ WKH EDVLV RI SKDVH FXUUHQW PHDVXUHPHQWV 0LFURORJLF

RIIHUV WKLV SURWHFWLRQ IXQFWLRQ ZLWK DGMXVWDEOH SLFN XS ,J DQG WLPH GHOD\

Instantaneous protection I (Ii)

A-19

7KLV SURWHFWLRQ VXSSOHPHQWV ,VG ,W SURYRNHV LQVWDQWDQHRXV RSHQLQJ RI WKH GHYLFH

7KH SLFN XS PD\ EH DGMXVWDEOH RU ¿[HG EXLOW LQ 7KLV YDOXH LV DOZD\V ORZHU WKDQ WKH

FRQWDFW UHSXOVLRQ OHYHO

Long-time protection L (Ir)

A-19

3URWHFWLRQ IXQFWLRQ ZKHUH WKH DGMXVWDEOH ,U SLFN XS GHWHUPLQHV D SURWHFWLRQ FXUYH

VLPLODU WR WKH WKHUPDO SURWHFWLRQ FXUYH LQYHUVH WLPH FXUYH ,

2

W 7KH FXUYH LV JHQHUDOO\

GHWHUPLQHG RQ WKH EDVLV RI WKH ,U VHWWLQJ ZKLFK FRUUHVSRQGV WR D WKHRUHWLFDOO\ LQ¿QLWH

WULSSLQJ WLPH DV\PSWRWH DQG RI WKH SRLQW DW ,U DW ZKLFK WKH WULSSLQJ WLPH GHSHQGV

RQ WKH UDWLQJ

Magnetic protection (Im)

A-14

6KRUW FLUFXLW SURWHFWLRQ SURYLGHG E\ PDJQHWLF WULS XQLWV VHH WKLV WHUP 7KH SLFN XS

VHWWLQJ PD\ EH ¿[HG RU DGMXVWDEOH

*

( LQGG

YHUVLRQ