Presentation is loading. Please wait.

Presentation is loading. Please wait.

Co-ordination of LV Protection Devices DBTP107PRE-En-07/00 E58640.

Similar presentations

Presentation on theme: "Co-ordination of LV Protection Devices DBTP107PRE-En-07/00 E58640."— Presentation transcript:

1 Co-ordination of LV Protection Devices DBTP107PRE-En-07/00 E58640

2 DBTP107PRE-En-07/00 2 Contents Operator needs Availability of electrical energy3 Co-ordination of LV protection devices 8 Co-ordination techniques 12  The IEC standard 12  Discrimination techniques 16  Limitation21  Cascading23 Schneider solutions 24  Masterpact and the incoming end of the installation25  Compact NS and power distribution 30  Multi 9 circuit-breaker and final distribution 33  Discrimination rules for 1 to 6300 A34 Conclusion35

3 DBTP107PRE-En-07/00 3 From one application to another operator needs are the same …The availability of electrical energy

4 DBTP107PRE-En-07/00 4 The availability of electrical energy Savings for the operator through:  the continuity of electrical supply  the optimised cost of his installation …A source of profit for the operator

5 DBTP107PRE-En-07/00 5 Availability of electrical energy and the LV protection plan Structure of LV Distribution Level 1General LV = incomer Switchboard Level 2 = MSB feeders Distribution Level 3Switchboard = poweror distributionmotor control Level 4Final = final distributionswitchboards distribution Loads E62649

6 DBTP107PRE-En-07/00 6 Availability of electrical energy and the LV protection plan Structure of LV Distribution Installation design  priority / non priority feeders Protection of LV distribution  level 1 and 2: using Air Circuit-Breaker (ACB) or Moulded Case Circuit-Breaker (MCCB) with high rating 800 to 6300 A  level 3: using LV industrial Fuse or Moulded Case Circuit-Breaker (MCCB) 63 to 1250 A  level 4: using Miniature Circuit-Breaker (MCB) 1 to 100 A

7 DBTP107PRE-En-07/00 7 Customer needs Continuity of electrical energy supply Cost of the electrical installation Co-ordination of protection devices: discrimination, cascading & constraint limitation Protection Plan Availability of electrical energy and the LV protection plan

8 DBTP107PRE-En-07/00 8 LV co-ordination techniques Optimising LV electrical distribution through 3 actions at the Protection Plan Level  1) discrimination to guarantee continuity of supply  2) limitation to reduce constraints  3) cascading to optimise performances

9 DBTP107PRE-En-07/00 9 Co-ordination of protection devices 1) discrimination Whatever the fault:  overload  short-circuit  insulation fault only the circuit-breaker located just upstream from the fault trips 4 types of discrimination  current  time  energy  logic E41139

10 DBTP107PRE-En-07/00 10 Co-ordination of protection devices 2) limitation Technique that allow for the harmful effects of short-circuit currents to be diminished Limitation reduces effects of the following type:  electromagnetic: reduction in EMC disturbances  mechanical: reduction of deformation and/or breaks  thermal: rise in the life span of trunkings E62650 E62651 Isc presumed transient peak Isc presumed steady peak Isc limited peak Isc 10 % Â tsc t 100 % t A2A2 I 2 sc Presumed energy 100 % Limited energy < 1 % 1 % 100 %

11 DBTP107PRE-En-07/00 11 Co-ordination of protection devices 3) cascading The limiting upstream circuit-breaker helps the downstream circuit-breakers to open Technique that allows for the cost of LV electrical distribution to be optimised E62667 Non priority feeder

12 DBTP107PRE-En-07/00 12 The IEC standard and co-ordination of protection devices Recognises the 2 co-ordination elements (appendix A)  discrimination  cascading Defines testing to guarantee this co-ordination Characterises the circuit-breakers capable of time discrimination  utilisation category B E55229

13 DBTP107PRE-En-07/00 13 The IEC standard appendix A discrimination Definition of the discrimination limit Is Tests to be conducted E62654E62653

14 DBTP107PRE-En-07/00 14 The IEC standard appendix A cascading Definition of the current IB and of the reinforced breaking capacity IcuD2+D1 Tests to be conducted E62680E62681

15 DBTP107PRE-En-07/00 15 The IEC standard category B circuit-breakers They ensure time discrimination that is characterised by Icw during  t  Icw must be at least equal to 12 I n or 5 kA for I n  2500 A 30 kA for I n > 2500 A   t - standardised delay - of: or 1 s They are subjected to additional testing E62652

16 DBTP107PRE-En-07/00 16 Quality of discrimination Comparison of the discrimination limit Is to the presumed short-circuit current Isc determines the quality of discrimination  total discrimination: Is > Isc  partial discrimination: Is < Isc  if the discrimination limit is equal to the Icu of the upstream circuit-breaker discrimination is total LV discrimination techniques only D2 tripsD1 and D2 trip E62682

17 DBTP107PRE-En-07/00 17 Current discrimination Linked to the natural staging of Long Delay curves of the association  discrimination limit Is = Isd1  discrimination technique generally used in Final Distribution E62655

18 DBTP107PRE-En-07/00 18 Time delay  t of the upstream circuit-breaker’s Short Delay CR tripping  extension of current safety  discrimination limit Is = Ii1 (= Icw1)  discrimination technique generally used on the incoming end of the installation the upstream circuit-breaker is from category B with a high EDW (Icw1 = Icu1) Time discrimination E62683

19 DBTP107PRE-En-07/00 19 Comparison of energy curves (tripping D downstream/non tripping ND upstream) allows for the discrimination limit Is to be determined Only the manufacturer can guarantee the quality of discrimination of the energy type Energy discrimination E62656 E68104 D Tripping ND Non tripping

20 DBTP107PRE-En-07/00 20 Logic discrimination (ZSI) Circuit-breakers fitted out with electronic trip units  a pilot wire between upstream / downstream circuit-breakers  no threshold rules This technique  is easily implemented  reduces to a minimum constraints from delayed tripping of time discrimination E62659

21 DBTP107PRE-En-07/00 21 Technique consists in using the arc voltage to limit short-circuit currents 3 criteria to be considered  early  fast  high Technique that has multiple advantages  limitation of constraints on the installation  better discrimination  circuit-breaker cascading Limitation I asymetric peak Isc ILIL E62660 earlyfast high E68105

22 DBTP107PRE-En-07/00 22 The use of a limiting downstream circuit-breaker extends current and/or time discrimination with the upstream circuit-breaker The downstream circuit-breaker by limiting the fault current Id increases the discrimination limit Is Improving discrimination through limitation E62657 D2 non limiting D2 limiting Isc in D2 Isc (D2) presumed Is D2 limitingD2 non limiting Is

23 DBTP107PRE-En-07/00 23 The use of a limiting upstream circuit-breaker “increases” the breaking capacity of the downstream circuit-breaker Technique that allows for the installation of a limiting circuit-breaker downstream from circuit-breakers with optimised Breaking Capacities Cascading E62661 E62662

24 DBTP107PRE-En-07/00 24 Schneider solutions Customer needs Continuity of electrical energy supply Cost of the electrical installation Discrimination as a standard in the circuit-breaker ranges Economical association of circuit-breakers through Cascading Totally co-ordonated Schneider protection devices Constraint Limitation

25 DBTP107PRE-En-07/00 25 Discrimination upstream: setting the long delay (LR) slope (IDMTL) allows for better discrimination Discrimination downstream:  better time discrimination thanks to higher Icw  on very high Isc (up to 150 kA), maintains a high level of discrimination Limitation of very high constraints Masterpact offers unequalled performances as a standard for all applications Masterpact power circuit-breakers E62663

26 DBTP107PRE-En-07/00 26 Improving MV/LV discrimination thanks to IDMTL curves 5 suggested slopes:  DT: definite time  SIT: inverse standard time  VIT: very inverse time  EIT: extremely inverse time  HVF: HV compatible fuse E62664 HVF curve tr = 2 s MV Fuse 80 A brought to LV I 2 t curve tr = 12 s Short delay threshold = 4 Ir

27 DBTP107PRE-En-07/00 27 Ensuring total time discrimination as a standard Time discrimination with very high Icw (up to 85 kA 1s) thanks to:  a globally reinforced mechanism, enclosure, copper parts  the use of air CTs for measurement Accuracy zone of the instantaneous tripping threshold (± 10 %) Maximum time discrimination Icw = thermal withstand = self-protection DIN threshold E62675 E62676 NW H

28 DBTP107PRE-En-07/00 28 Increasing the breaking capacity without sacrificing discrimination Conciliate high breaking capacity (150 kA) and high Icw (65 kA -1s) Disengagement E62665 Kinematic chain Half moon actvating the pole shaft Effort sensor E

29 DBTP107PRE-En-07/00 29 Limiting as much as possible the constraints on the incoming end of the installation Limitation  using disengagement for very fast breaking  modification of the fixed pole to increase the repulsion force Time discrimination up to 37 kA Unequalled performances for a limiting circuit-breaker Breaking chamber Magnetic U U-shaped current loop E62666 E68106 E62678 Total breaking time Presumed short-circuit current Limited current Intervention time

30 DBTP107PRE-En-07/00 30 New breaking technology  roto-active breaking Compact NS power distribution E62669 E62670  Fixed contact Breaking enclosure Breaking chamber Mobile contact Fixed contact Piston Short-circuit current Breaking chamber Arc New breaking technology  roto-active breaking  pressure (“reflex” tripping)  E62670 E62669 Fixed contact Breaking enclosure Breaking chamber Mobile contact Fixed contact Piston Short-circuit current Breaking chamber Short-circuit current Provides an exceptional limiting capacity Fixed contact Breaking enclosure Breaking chamber Mobile contact Fixed contact E62670 E62669 Piston

31 DBTP107PRE-En-07/00 31 Natural discrimination Compact NS circuit-breakers have natural discrimination performances  current and/or time tripping curves  natural discrimination energy curves E62671 E

32 DBTP107PRE-En-07/00 32 Compact NS circuit-breakers have natural Cascading performances  reflex tripping (piston) Reinforced Breaking Capacity without loss of Discrimination Simultaneous discrimination and cascading E D1 D2

33 DBTP107PRE-En-07/00 33 Final distribution Multi 9 circuit-breakers Technology with magnetic actuator Guaranteed performances  ultra rapid breaking  exceptional limitation  total discrimination with circuit-breakers located upstream E

34 DBTP107PRE-En-07/00 34 Masterpact  total discrimination with Compact NS (<630 A) circuit-breakers located downstream Compact NS  total discrimination as soon as the ratio between ratings is greater than 2.5 Note: it is necessary to conserve current and time threshold staging The Schneider solution ensures total natural discrimination from 1 to 6300 A Schneider discrimination rules

35 DBTP107PRE-En-07/00 35 The Schneider solution: mastering the technique Continuity of supply thanks to total discrimination E62679 Compact NS 1 to 160 A CA production Recording box Factory assembly line

36 DBTP107PRE-En-07/00 36 The Schneider solution: mastering the financial aspect Upon installation During operation Thanks to the quality of limitation of these circuit-breaker ranges E43481E43480

37 DBTP107PRE-En-07/00 37 The Schneider solution: mastering services Simple and high-performance tools  software:Ecodial 3  catalogue:Exhaustive choice table E43477 E43478 E43476 LV Catalogue

38 DBTP107PRE-En-07/00 38 Schneider offers circuit-breaker ranges from 1 to 6300 A with unequalled performances Standards are respected Performance of co-ordinations:  discrimination as a standard  highly economical cascading Simple and high-performance catalogues and software Schneider guarantees a safe and high- performance electrical installation for mastering the LV protection plan “No one in the world does more with electricity” CT150fi E E68107

Download ppt "Co-ordination of LV Protection Devices DBTP107PRE-En-07/00 E58640."

Similar presentations

Ads by Google