Presentation on theme: "What about type tested assemblies?"— Presentation transcript:
1 What about type tested assemblies? The tested switchboard, complying with IEC1
2 IEC standards are based on the consensus and knowledge find among the best experts in the world.They provide minimum requirements and test procedures for safe and reliable installation allowing a high availability of the electrical energy
3 What is a switchboard used for ? To gather and protect the control and protective devices together with electrical and mechanical connections against external influences.To inform the end-user on the state of his installation.To protect the switchboard user against the main risk of accidents (direct contact protection, indirect contact protection and fire risk).To evolve with the activityPrésence d’une AnimationInstallations monitoringand controlProtection for individualsElectrical power distribution
4 The LV electrical switchboard has to be safe and available It is a question of balance between:the needs of safety and availabilitythe constraints of reliability and maintenability of the installation.SafetyMaintenabilityReliabilityAvailabilityPrésence d’une Video
5 Low-voltage switchgear and controlgear assemblies IEC seriesLow-voltage switchgear and controlgear assembliesOne general standard :IEC type-tested assemblies (TTA) and partially type-tested assemblies (PTTA)Four related standards:IEC busbar trunking systems (busways)IEC distribution boards (<250A, unskill people)IEC assemblies for construction sites (ACSs)IEC cable distribution cabinets (CDCs)
6 What about the main features? The tested switchboard, complying with IEC1
7 IEC 60439-1, what about the scope? Scope : Low-voltage switchgear and controlgear assembly, TTA or PTTA, whose rated voltage is 1000 Vac or 1500 Vdc.TTA : type-tested assemblies conforming to an established type or system without deviations likely to significantly influence the performance, from the typical ASSEMBLY verified to be in accordance with this standard. A full range of representative configurations have been tested.PTTA : partially type-tested assemblies, containing both type-tested and non type-tested arrangements provided that the latter are derived (e.g. by calculation) from type-tested arrangements which have complied with the relevant tests. Some limited configurations may be tested.Definition : A combination of one or more low-voltage switching devices together with associated control, measuring, signalling, protective, regulating equipment, etc., completely assembled under the responsibility of the manufacturer with all the internal electrical and mechanical interconnections and structural partsEither a TTA or a PTTA equipment meeting IEC afford the same quality level
8 The IEC 60439-1 standard gives general rules for switchboards construction Meeting IEC requirements means :a minimum level of safety for people and equipmentto include the low-voltage switchgear and controlgear assemblies for the power distribution and controlprecise requirements for- service conditions (temperature...)- construction requirements (IP, IK, forms,...)precise test proceduresIEC : one worldwide standard for all the professionals of switchboards.SafetyMaintenabilityReliabilityAvailabilityConformity to IEC providesan insurance on switchboard realization quality
9 Classification according to IEC 60439-1 external design (open-type, dead front, enclosed, busway)place of installation (indoor - outdoor)conditions of installation with respect to mobility (stationary - movable)degree of protection (for outdoor IP 3X)type of enclosure (e.g metallic or plastic)method of mounting (fixed or removable)measures of protection of personsform of internal separation (to be detailed, agreement between customer and manufacturer)types of electrical connections of functional units (to be detailed, agreement between customer and manufacturer)
10 IEC 60439-1 : Functional unit Functional unit Definition : Part of an assembly, comprising all the electrical and mechanical elements that contribute to the fulfilment of the same functionExample : drawer in a Motor Control Centre switchboard .IncomingOutgoingAuxiliaryFunctional unit
11 IEC 60439-1 proposes different type of secured forms adapted to each situation V. FormsIn most installations, no particular partitioning is needed, electrical switchboard of the form 1 type is acceptable.However this is no longer true without a front plate or other equivalent mean. The user shall not access to living parts.Following forms 2, 3 and 4 introduce additional partitioning within the switchboardForm 2: partitioning of busbarsForm 3a and 3b:functional units separated from each other and separated from the busbarsconnecting terminals separated from busbarsForm 4a and 4b:connecting terminals separated from each other and separated from busbars.
12 IEC 60439-1 The forms of internal separation Form 2aForm 3aForm 4aForm 2bForm 3bForm 4b1. Maintenance people should not be in a dangerous situation, e.g. parts not under maintenance should not create dangerous situation in parts under maintenance2. Maintenance in one part should not create a dangerous situation in another part e.g. a screw or a tool falls in another part3. Danger in one part should not expand to other parts e.g. an arc in one part should not influence other parts
13 Electrical connections for functional units BTypes of electrical connections of functional units (FU)F = FixedD = DisconnectableW = WithdrawableIdentificationconnections are codified with these 3 letters referring to :1st : main incoming circuit2nd : main outgoing circuit3rd: auxiliary circuits
14 What about test procedure ? The tested switchboard, complying with IEC1
15 The tests of standard IEC 60439-1 BThey guarantee that the switchboard complies with the necessary standard requirementThere are two type of tests:7 type tests are performed by the manufacturer on one or several configurations:n°1 temperature rise limitsn°2 dielectric propertiesn°3 short-circuit withstandn°4 protective circuit effectivenessn°5 clearances and creepage distancesn°6 mechanical operationn°7 degree of protection.3 routine tests are performed by the panelbuilder on each particular switchboard:n°8 general inspectionn°9 insulation/dielectric testn°10 protection measures.
16 The 7 type tests performed by the manufacturer The aim of these tests is to confirm the switchboardcharacteristics.The 7 type tests are carried out on the most difficult and unfavourable system configurations. The assembled and cabled switchboards are made up of their usual components, connection system…, equipped with switchgear and assemblied and installed according to industrial standards.The tests are conducted either in approved laboratories (Asefa, Kema, Lcie,…), or in a manufacturer laboratory.
17 (8-2-1): temperature rise limits Test n°1(8-2-1): temperature rise limitsTest performed by the manufacturerGuarantees the safety and reliability of the switchboard, by avoiding problems such as:connection damagesreduction in insulation performancesrisk of burn for maintenance operatorselectronic components damagesfaulty operation of the devices: inopportune release.How to proceed:to measure the temperature of each equipment, after a delay allowing a stabilized temperature, when each circuit is used at its rated power and when the complete switchboard is loaded with an appropriate diversity factorResult to be obtaintemperature rise shall not exceed what the different equipment can withstandthe temperature of accessible surfaces has to be checked
18 (8-2-2): dielectric properties Test n°2(8-2-2): dielectric propertiesTest performed by the manufacturerGuarantees the switchboard safety and reliability, to avoid problems such as:electrical arc generationinsulation performance decreasingconnection damagesWithstand impulse voltage test and an ac test are performed
19 (8-2-3): short-circuit withstand Test n°3(8-2-3): short-circuit withstandTest performed by the manufacturerThis test simulates an incident which could occur on site.Withstanding the short-circuit currents is:to avoid danger (rupture and projections of components, arc generation and propagation outside the switchboard,...)it also means the installation can be quickly put back into operation after the incident.Relationship between peak current (Ipk) and short-circuit current (Icw):Ipk = Icw x nRMS value of short-circuit current kA eff/1s (Icw)nIpk (kA)Icw £ 51.5Ipk £ 7.55 < Icw £ 101.78.5 < Ipk £ 1710 < Icw £ 20220 < Ipk £ 4020 < Icw £ 502.142 < Ipk £ 10550 < Icw2.2110 < Ipk
20 (8-2-4): effectiveness of the protective circuit Test n°4(8-2-4): effectiveness of the protective circuitTest performed by the manufacturerThe effectiveness of the protective circuit is verified by two tests:resistance measurement of the connection between the exposed conductive parts and the protective circuitsshort-circuit withstand performed between the protective conductor and the nearest phase conductor.
21 (8-2-5): clearance and creepage distances Test n°5(8-2-5): clearance and creepage distancesTest performed by the manufacturerClearance control: shortest distance between two conductive parts.Creepage distance control: shortest distance along the surface of an insulating material between two conductive parts.
22 (8-2-6): mechanical operation Test n°6(8-2-6): mechanical operationTest performed by the manufacturerEndurance of material, guaranteeing the longevity of the various mechanisms.The standard requires 50 operating cycles.
23 (8-2-7): degree of protection (IP, IEC 60529) Test n°7(8-2-7): degree of protection (IP, IEC 60529)Test performed by the manufacturerThe tests carried out define the capacity of an equipped switchboard to:protect persons against contact with live partsprotect equipment against penetration of solid objects and liquidsIP1st digit:protection of personsprotection against solids.2nd digit: protection against liquids.Note: in case of only protection of persons is needed, the 2 IP digits are replaced by x.Example: IPxxB.Additional letter (optional): protection of persons against contact with live parts:A: protect againts access of the back of the handB: protect against access of fingers Ø 12 mmC: protect against access of a tool Ø 2.5 mmD: protect against access of a tool Ø 0.1 mm.
24 The 3 tests performed by the panelbuilder These 3 routine tests can be easily and rapidly performed by the panelbuilder:overall inspection according to the mounting instructions and technical documents (right device ratings, tightening torques)insulation checking by a dielectric testchecking of protective measures and of the electrical continuity of the protective circuits.They complete the 7 manufacturer type tests and guarantee professionnalism and responsability of panelbuilder.3 routine tests performed by the panelbuilder:n°8 general inspectionn°9 insulation/dielectric testn°10 protection measures.
25 (8-3-1): general inspection Test n°8(8-3-1): general inspectionTest performed by the panelbuilderCheck of mechanical actuating elements, interlocks,... effectiveness.Check of proper laying of conductors and cables and proper mounting of device.Check of connections adequate contact, especially screwed and bolted connections.
26 (8-3-4): insulation resistance/(8-3-2): dielectric test Test n°9(8-3-4): insulation resistance/(8-3-2): dielectric testTest performed by the panelbuilderNo arc flash-over or insulator perforation must be observed between the live parts each other and between the live parts and the conductive structural parts.
27 (8-3-3): protective measures Test n°10(8-3-3): protective measuresTest performed by the panelbuilderChecking of protective measures and of the electrical continuity of the protective circuits for metallic assemblies.
28 What about the benefits? The tested switchboard, complying with IEC1
29 The benefits from IECIEC provides minimum requirements and test procedures for safe and reliable installation allowing a high availability of the electrical energySpecifiers/consultants:the certainty to prescribe a switchboard which ensures the level of safety required by the userPanel-builder / Installer:confidence in products and swichboards systems, following the standardincrease efficiency, easy to show conformityManufacturer:products tested in real configurationsdetailed instructions for fautless construction.