8/9/2019 LV Network Calculations and Use of Amtech

1/38

LV Network Calculations& Use of Amtech

 Jyothimon Abraham,Msc,B.E

Senior Electrical Engineer,B.K Gulf,Dubai

8/9/2019 LV Network Calculations and Use of Amtech

2/38

Not very simle !or"e" as DE#A$ADE#A etc.

But lot of ne! terminologies

%evelation of Design &rocess

Kno!ing many stan"ar"s hels to 'no! !here !estan" right no!

Soun" Engineering Decisions are a result of 'no!ingof (omonents involve", )n"erstan"ing of relate"stan"ar"s an" e*eriencing of rocess involve"

WHY BS767 !S!"#$%AN

8/9/2019 LV Network Calculations and Use of Amtech

3/38

(AB+E S-NG /0+1AGE D%0& (A+()+A10NS

S20%1 (%()1 EA%12 3A)+1 S1)DES

DS(%MNA10N S1)DES %E+A4 SE1NG

AM1E(2 &%A(1(E SESS0N

$#!CS C$V'%'(

8/9/2019 LV Network Calculations and Use of Amtech

4/38

CABLE SIZING

CALCULATIONSBased on BS7671 & DEWA Regulations

8/9/2019 LV Network Calculations and Use of Amtech

5/38

HEATING EFFECT ON CABLES

  Concept of Thermal Equilibrium

  Heat energ generated b Cable ! Heat

energ dissipated b cable into the

en"iornment

8/9/2019 LV Network Calculations and Use of Amtech

6/38

  CORRECTION FACTORS-BASED

ON ERA STUDIES

Cable derating is done for a"oiding cables sub#ect to

Thermal stress$

Cables on %ree ir

  mbient Temperature %actor 'Ca(

  )rouping %actor 'Cg(

*+ecide the method of ,nstallation from TB-E*./

  Thermal ,nsulation %actor'Ci(

Cables 0nder )round  +erating factors are a"ailable for +epth of Burial

%or )round Temperature %or )round Thermal

Resisti"it b ,EC$ mtech allo2 user defined

+erating %actors to be incorporated$

8/9/2019 LV Network Calculations and Use of Amtech

7/38

DETERMINATION OF CABLE SIZE

  +esign Current ',b(

  3ominal Current',n ( of the 4rotecti"e +e"ice

  Tabulated Current Carring Capacit',t (

  Criterion  ,n ,b

   

8/9/2019 LV Network Calculations and Use of Amtech

8/38

  TABLE LOOK UP

8/9/2019 LV Network Calculations and Use of Amtech

9/38

  AMTECH CABLE INTERFACE

8/9/2019 LV Network Calculations and Use of Amtech

10/38

VOLTAGE DROP CALCULATIONS

  *Correction for perating Temperatures

  *Correction for -oad 4o2er %actors

  *Correction for Temperature & -oad 4o2er

%actors

   

8/9/2019 LV Network Calculations and Use of Amtech

11/38

AMTECH APPROACH TO V.D

8/9/2019 LV Network Calculations and Use of Amtech

12/38

 VOLTAGE DROP INTERFACES

8/9/2019 LV Network Calculations and Use of Amtech

13/38

  MOTOR STARTING VOLTAGE

DROP

  oltage*sensiti"e de"ices such as dri"es 2ill

drop out if "oltage drop e8ceeds 19:$

  ;

8/9/2019 LV Network Calculations and Use of Amtech

14/38

  THANK YOU

estions

8/9/2019 LV Network Calculations and Use of Amtech

15/38

EA%12 3A)+1S20%1 (%()1S1)DESBS 5657 ,E(

689:5,BS5:;8

8/9/2019 LV Network Calculations and Use of Amtech

16/38

 10)(2 /0+1AGE ()%/E ;8mA for < sec is

safe as er touch

voltage curve s D.( Shoc' 0%

A.( Shoc' high=

(omaring 1ouch

voltage curves ,".cgets "angerous at7>8mA,7sec.

8/9/2019 LV Network Calculations and Use of Amtech

17/38

EA%12 3A)+1

 1E%MN0+0G4 10)(2 /0+1AGE?Direct Shoc' Situation@

)t

)t

8/9/2019 LV Network Calculations and Use of Amtech

18/38

Sulemtary Bon"ing )t

 1his metho" is calle" Earthe" EFuiotentialBon"ing Automatic Disconnection ofsulyCEEBAD0S

8/9/2019 LV Network Calculations and Use of Amtech

19/38

SA3E DS(0NNE(10N 1ME

8.: secon"s for small o!er outlets an"nal sub circuits not e*cee"ing 6;A

> secon"s for sub mains an" nal subcircuits fee"ing *e" eFuiment

8/9/2019 LV Network Calculations and Use of Amtech

20/38

EA%12 +00& M&EDAN(E

8/9/2019 LV Network Calculations and Use of Amtech

21/38

S20%1 (%()1 1E%MN0+G4 &%0S&E(1/E S20%1

(%()1 ()%%EN1

&EAK 3A)+1 ()%%EN1#12S1AND

(&D B%EAKNG(A&A(14

NS1AN1ENE0)S 1%&

()%%EN1H (AS(ADE %A1ED

B%EAKNG (A&A(14

8/9/2019 LV Network Calculations and Use of Amtech

22/38

&revention Arc 3lash 2aIar"

)se of &&E

8/9/2019 LV Network Calculations and Use of Amtech

23/38

  ADABA1( (2E(K  K 

8/9/2019 LV Network Calculations and Use of Amtech

24/38

me"ance Diagrams

8/9/2019 LV Network Calculations and Use of Amtech

25/38

  ILB)S (0N(E&1

8/9/2019 LV Network Calculations and Use of Amtech

26/38

  than' you

estions

8/9/2019 LV Network Calculations and Use of Amtech

27/38

(!SC%!"!NA!$NSU(!'S & %'LAYS'!N)

8/9/2019 LV Network Calculations and Use of Amtech

28/38

'L'C%$N!C %!#CHA%'C'%S!CS $* B%'A+'%

2o! many (ycles!ithstan" anEFuiment canEn"ure=

8/9/2019 LV Network Calculations and Use of Amtech

29/38

)%$UN( CHA%AC'%!S!CS $*B%'A+'%

8/9/2019 LV Network Calculations and Use of Amtech

30/38

(!SC%!"!NA!$N L!"!

8/9/2019 LV Network Calculations and Use of Amtech

31/38

C$NC'# $* !"' )%A(!N)

• belo! 8.8> sec or three cycles on the time a*is isthe instantaneous tri function

• Short time settings cover the time range from8.8> to 8.> sec Cthree to ;8 cycles.

• +ong time settings cover the time range from 8.>to 7888 sec.

• Ma* tri time of

8/9/2019 LV Network Calculations and Use of Amtech

32/38

Conce,t of -$N!N)

8/9/2019 LV Network Calculations and Use of Amtech

33/38

Y#'S $* (!SC%!"!NA!$N

•  1ime Discrimination

• Energy Discrimination

• -one Selective Discrimnation

8/9/2019 LV Network Calculations and Use of Amtech

34/38

A"'CH (!SC%!"!NA!$N!N'%*AC'

8/9/2019 LV Network Calculations and Use of Amtech

35/38

A"'CH %'LAY S'!N)!N'%*AC'

8/9/2019 LV Network Calculations and Use of Amtech

36/38

  #'%*'C (!SC%!"!NA!$N

8/9/2019 LV Network Calculations and Use of Amtech

37/38

-$N' S'L'C!V'!N'%L$C+!N)

8/9/2019 LV Network Calculations and Use of Amtech

38/38

  HAN+ Y$U

Questions