PANELS - Norðurál

PANELS - Norðurál


NORÐURÁLNORDIC ALUMINUMSTANDARD TECHNICAL SPECIFICATION00/06/TS023TECHNICAL SPECIFICATION1 General information1.1 GeneralIn this Document the following words and expressions shall have the meaning herebyassigned to them except where the context otherwiserequires:Engineer:The Owner or any person or organisation employed or engaged at any time bythe Owner and authorised by the Owner, in writing, from time to time to act onbehalf of the Owner in the execution of the items covered by this Document, inwhole or in any part, for any or all purposes provided in this TechnicalSpecification.Owner:Norðurál hf (Nordic Aluminum Corporation Ltd.), an independent legal entityowned by Century Aluminum.This Specification defines and covers the general standards of workmanship, materialrequirements and construction methods that are required in the execution of theelectrical installation work. Trained, skilled and qualified electricians who areexperienced in electrical installation work for projects shall carry out the work.All floor mounted, vermin proof, folded sheet steel, compartmentalized, tiered top,power distribution panels, distribution panels, motor control and distribution gearpanels, having single or double busbars system, control desks, control and relaypanels, and marshalling boxes that contain electrical equipment, hereafter calledPanel, shall comply with all appropriate clauses of this Specification.The Panel is comprised of a number of free standing, floor mounted folded sheet steelpanels, of minimum thickness 2,0 mm to ensure rigidity of each unit and of allsurfaces. These panels shall be damp and dust protecting and vermin proof inaccordance with approved EN standards. The panels shall be jig constructed tostandard patterns and accommodated on a common channel underbase. All panelsshall be robustly constructed of approved material suitable for the application andshall have a high quality finish and appearance. They shall be of type IP54 or higherand if required for outdoor duty of type IP56 or higher and shall be suitable for theenvironment.NORÐURÁL25/05/2004, REV. C1- 3 / 14 -

NORÐURÁLNORDIC ALUMINUMSTANDARD TECHNICAL SPECIFICATION00/06/TS023The Contractor shall furnish all labour, materials, equipment, tools, service andtemporary works to provide and complete the electrical installation in perfectoperation to the satisfaction of the Engineer, including all testing to demonstrate thatthe entire installation is in perfect working order. This work shall include builder'swork if necessary, such as the fixing of supports or brackets and cutting or formingopenings, chasmes, etc., in floors/walls for installation purposes, and finishing upproperly afterwards.1.2 Electrical system1.2.1 The power electrical system shall be:400 Volt, 3 Phase, 50 Hertz AC5 wire system, (3 Ph – N - PE)Neutral solidly earthed TN-C-SFault level 28,5 MVA.1.2.2 Auxiliary supplies shall be:230 Volt, 1 Phase, 50 Hertz AC3 wire system, (1 Ph – N - PE)Neutral solidly earthed TN-C-SIn some situations:110 Volt, 1 Phase, 50 Hertz AC3 wire system, (1 Ph – N - PE)One side earthedAccording to IEC Publication 60364-3, subjected to statutory variations in voltageand frequency.1.3 Compliance with regulations and standardsAll materials supplied by the Contractor shall be new of first quality and/or certifiedfor the purpose for which they shall be used, have CE markings and comply with allrelevant European Standards, where such standards exist. All components andmaterials shall comply with the relevant IEC standards, in addition to therequirements detailed in this Specification.Where the Contractor offers materials or equipment which conforms to otherstandards than those mentioned above, the Contractor shall supply to the Engineer fulldetails of the differences between the different standards, at the earliest possible stageof the works. Equipment so supplied shall be used only subject to the writtenapproval of the Engineer.NORÐURÁL25/05/2004, REV. C1- 4 / 14 -

NORÐURÁLNORDIC ALUMINUMSTANDARD TECHNICAL SPECIFICATION00/06/TS023The Contractor shall keep a copy of the aforementioned regulations, supplements,addenda or published revisions on site at all times for the duration of the contract.2 Panel constructions2.1 ConstructionThe panels shall be metal clad and shall be sized to suit the Electrical Design. It shallbe suitable for free standing or wall mounting to IP54 classification. The distributionpanel shall be manufactured in accordance with the requirements of VDE and IECstandards and Icelandic laws and regulations.Hinged doors shall be of the lift-off type and shall be capable of being opened throughat least 150 degrees. A pocket shall be provided on all panel doors for electricaldrawings and cable termination charts to be supplied by the Contractor. All doorsshall be provided with locking facilities.The interior of the panel shall be illuminated and so arranged that all internal wiringand terminations are visible without dazzle. Internal lights shall be controlled from acommon door switch. In view of the exceptional site conditions, low watt panelheaters shall be provided to prevent condensation in the interior part of all panels.These heaters shall be suitable for 230 V single phase, 50 Hertz, AC supply, and shallbe provided with suitable protection or circuit breakers.All equipment shall be fixed by screws on the rear mounting plate or rails. Equipmentremoval must be easy from the front of the panel. No equipment is allowed to bemounted to the bottom, top or the sidewalls of the cubicle. All apparatus shall bemounted in such a manner as to permit easy access to all components.Isolating devices shall be provided for incoming power supplies to all panels. Eachpanel of nominal load above 16 A shall be equipped with a main load switch allowingmanual disconnection of the nominal load.All electrical equipment shall be physically separated from pneumatic or hydraulicequipment and pipework. If pneumatic or hydraulic equipment is located in the samepanel as electrical equipment, the panel must be split up into two independentcompartments.2.2 Materials and testing of materialsAll materials, equipment and workmanship for the whole of the installation shallcomply with Icelandic laws and regulations. All materials shall be new. Anymaterials or workmanship not accepted and approved by the Engineer shall beremoved and replaced by the Contractor at his own expense. The Engineer shall andNORÐURÁL25/05/2004, REV. C1- 5 / 14 -

NORÐURÁLNORDIC ALUMINUMSTANDARD TECHNICAL SPECIFICATION00/06/TS023will have the authority to reject any materials and/or workmanship that, in its opinion,are unsatisfactory, and to instruct the Contractor to rectify the same forthwith at theContractor's expense. All materials or equipment shall be delivered to the sitecomplete with proper packing and any materials or equipmnet damaged in transit willbe rejected and replaced by the Contractor without charge.All bracket work and supporting steelwork, screws etc., shall be galvanised.The contractor will be required to carry out tests (factory acceptance tests) and supplytest certificates for panels, prior to the shipment of the panels. All tests must be inaccordance with Norðurál Technical Specification.2.2.1 SamplesBefore starting the work on site, the Contractor shall submit in writing for the writtenapproval of the Engineer, information about all apparatus and fittings which heproposes to use in the works. The Contractor shall prepare or obtain and promptlysubmit to the Engineer free of charge, for its written approval, samples of materialsand particulars as requested. All materials installed that are not identical to theapproved samples shall be rejected. After having approved them, the Engineer willand shall retain such samples as standard references until the completion of the works.2.3 FinishAll surfaces of the panel shall be thoroughly cleaned of rust and the like and all weldsshall be ground to present a smooth finish. A base coat of good quality zinc chromateshall be applied overall followed by two coats of hard drying alkyd-based paintproviding a Hammer tone or Eggshell finish. The colour of the exterior finish shall beRAL 7022 - Midgrey and the interior finish shall be subjected to approval of TheEngineer.2.4 Switchgear and starter cubiclesSwitchgear and starter cubicles shall be provided with hinged doors on the front, fittedwith substantial suitable catches operated by means of suitably plated type handles onthe front. The equipment contained in the cubicle must ensure that access cannot begained to bare and "live" equipment. Doors and rear access covers must be providedwith suitable gaskets of neoprene-bonded cork, sponge rubber, or polythene foam asrequired.In the case of motor starter cubicles, all equipment shall be mounted on substantialsuitable steel or insulating board base-plate, the minimum thickness of which shall be3 mm to 10 mm respectively. This baseplate shall be secured to the main frameworkNORÐURÁL25/05/2004, REV. C1- 6 / 14 -

NORÐURÁLNORDIC ALUMINUMSTANDARD TECHNICAL SPECIFICATION00/06/TS023by at least 4 setscrews provided with captive nuts on the main framework and shouldbe easily removable from the front of the cubicle.To permit free breathing of individual cubicles, a small air space should be allowedbetween the top and the bottom of the equipment baseplate and the main framework.To allow breathing via the rear of the cubicles, suitable screened and filtered ventsshould be provided at one or more of the rear access covers.3 Marking and labelling3.1 Marking and labellingAll panels shall be fitted with approved identification labels at the front. Removableitems of equipment shall be labelled on the removable part and on the relevant fixedpart. All electrical equipment, terminals etc., inside the panel cubicle must be markedclearly according to the electrical schematic diagram.Each circuit and each final sub-circuit shall be clearly labelled in an approved mannerindicating the equipment and/or area of supply. To this purpose, “Branch Lists” shallbe mounted in clear transparent envelopes indicating the outgoing final sub-circuits,their rating and the points they supply. They shall be fixed on the inside of thedistribution board. The “Branch List” form is available from Norðurál SeniorElectrical Engineer.4 Earthing and bonding4.1 Earthing and bondingThe earthing system shall be in accordance with the requirements of the relevant IECstandards and shall satisfy the Icelandic Electrical Regulation and shall be inaccordance with Norðurál Technical Specifications 00/06/TS021 and 00/06/TS022.Neither structural steel nor water pipes, separately or jointly, shall be used as an earthelectrode within the installation. All metal parts that do not form part of an electricalcircuit shall be connected by individual conductors to an earth bar, which shall runthroughout the length of each panel. A copper earthing bar having a suitablecross-section shall be fitted along the entire length of the panel at the bottom rear. Itshall be fitted with a substantial bolted type main earthing lug at both ends and similarlugs to suit the cross-section of the circuit cables at all intermediate terminal pointsalong the board. The steelwork of the panel and, in particular, the gland plate must besolidly and effectively bonded to the main earth bar. It is only allowed to have oneearth wire under each bolt or screw. The PE conductor, screens of all cables, thepanel, isolators, socket outlets, etc., shall be made electrically continuous, bondingrings and nipples being provided and fixed at all junctions and connections to allmetal clad fittings.NORÐURÁL25/05/2004, REV. C1- 7 / 14 -

NORÐURÁLNORDIC ALUMINUMSTANDARD TECHNICAL SPECIFICATION00/06/TS0235 Wires and Cables5.1 Cable entriesThe cable entry shall be effected at the bottom rear of each tier of cubicles and asubstantial gland plate or plates must be provided for effecting the termination ofcables. The bottom gland plate should be a minimum of 230 mm above the base plate.This shall be at least 250mm above ground level and shall be arranged so that thecables entering from below can rise vertically without bending. Means shall beprovided for access to the glands for tightening but this must allow for a reasonablyairtight assembly for panels. The cable entry shall be sealed with an approvednon-flammable, insulating, vermin-proof material.Where one gland plate is employed for terminating all cabling in a panel comprising atier of cubicles, separate suitably rated terminal blocks shall be provided for the powerand control circuit of each switchgear or motor starter. Each sub-terminal block shallbe provided with a protective cover labelled in accordance with its associated circuitand the minimum continuous rating of any terminal block shall not be less than 20 A.This section shall conform to approved EN standards.The preferred cabling arrangement, for power panels, shall accommodate theincoming/outgoing cables in a separate compartment on one side of the cubiclescontaining switchgear or starters. The cables shall be terminated on a suitable taildirect to the outgoing terminals of the switchgear, starter, overload relay or switch,and the control cores to a suitably located terminal block.5.2 CableAll cables (power or lighting and small power) shall be in accordance with NorðurálTechnical Specifications 00/06/TS021 and 00/06/TS022 and shall be, at least, of1000/600 volts grade type. Every care must be taken in running out the cables in orderto avoid damage to the conductor and insulation.5.3 Small wiringThe cubicles shall be complete with all necessary small wiring that shall be of typeH07V-K or equivalent with a minimum cross section of 1,5 mm². The small wiringshall be complete with interlocking type numbered ferrules corresponding to wirereference numbers on all related drawings, and shall be fitted with pressed end sleevelugs or other approved method. The small wiring shall be carried out in aworkmanlike manner and provided with adequate clamps, cleats and the like. Whereinter-panel wiring is necessary, suitable bushes of rubber, brass, bakelite, or similarNORÐURÁL25/05/2004, REV. C1- 8 / 14 -

NORÐURÁLNORDIC ALUMINUMSTANDARD TECHNICAL SPECIFICATION00/06/TS023material, must be fitted to holes in the steelwork through which the wiring passes. Allsmall wiring inside the cubicle shall be of flexible type.Note: Where a multi-strand insulated conductor is installed between the subsidiarybusbars, isolators and circuit breakers, care shall be taken that the cross-sections of theterminals and the like are rated to withstand the mechanical forces occurring underfault conditions. Soldered lugs must not be used on these conductors.6 BusbarsMain busbars shall be made of hard drawn conductivity copper, having a constantcross section throughout and rated as specified and shall be housed in a separatechamber at the top of the panels and fixed on "Non-Tracking" insulators at suitableintervals to withstand the dynamic forces under full short-circuit conditions. Thesebusbars shall be fully insulated by means of acceptable isolating sleeving. All busbarjoints or connections shall be plated and bolted together with plated steel bolts orclamps.The busbar chamber shall be completely sealed against the entry of ionised gasgenerated by a fault in the circuit breaker, motor starter or other outgoing circuitcubicle. Busbar chamber end covers shall be provided at the extremities of the board.Subsidiary busbars connecting individual cubicles to the main busbars shouldpreferably be constructed of a hard drawn high conductivity copper bar designed forthe same fault conditions as the main busbars and must be fully insulated withacceptable insulating sleeving.The subsidiary busbars must not be accessible from the front of a cubicles, and adesign which provides separate screening and access to the busbars at the rear of allcubicles would be preferred.The main and subsidiary busbar chambers should be interconnected and provided atthe back with a breather consisting of a drip-proof vent backed with a strong finemesh screen. Access to all busbar chambers should be provided by bolted typecovers.7 Auxiliary panel equipment, instrumentsWhere specified, indicating instruments shall be of the flush mounting type with asquare dial, a minimum of 75 mm across. They shall conform to the appropriate ENstandards.NORÐURÁL25/05/2004, REV. C1- 9 / 14 -

NORÐURÁLNORDIC ALUMINUMSTANDARD TECHNICAL SPECIFICATION00/06/TS023Ammeters that are mounted directly on the door of the cubicle and connected toflexible leads shall be Current Transformer (CT) operated on any starters rated at 1kW or more. When fixed to the stationary portion, this provision shall apply tostarters rated at 30 kW or above. CT operated ammeters are acceptable at any lowerwattage than those specified, should this be more suitable to the manufacturer.Where voltmeters are called for, they shall be protected by means of withdrawablecartridge type fuses or circuit breakers.7.1 Auxiliary relaysUnless otherwise specified, auxiliary relays will be mounted inside the panel and shallbe grouped to indicate clearly the associated control system. Relays withencapsulated coil windings and plug-in cases are preferred. All relays shall be closedwith transparent covers that shall be suitably retained. Relay contacts must beadequately rated for the required duty and must be suitable for prolonged repeatedoperations.7.2 Control switchesEach switch shall be equipped with a label plate engraved to show the switch position.Switches used for circuit breaker or contactor remote control shall be of thediscrepancy control type. Discrepancy switches shall require two independentmovements for operation. Switch contacts shall be suitable for making and breakingan inductive control circuit at the relevant DC supply voltage.7.3 Indication screens or lampsIndicating VDU screen or lamps shall be of the minimum power consistent with goodvisibility. They shall be so arranged that the replacement of bulbs and the cleaning ofglass can be easily carried out from the front of the desk or panel. The colours of alllamps and indications shall comply with the IEC 60073 standard and must beapproved by the Engineer prior to installation.7.4 Mounting of instruments and relaysInstruments and relays may be mounted on the doors or the fixed portions of thecubicles, but care must be taken to ensure that the instruments and relays are rigidlysupported and not subject to shock or vibration resulting from the operation ofcontactors or switchgear.NORÐURÁL25/05/2004, REV. C1- 10 / 14 -

NORÐURÁLNORDIC ALUMINUMSTANDARD TECHNICAL SPECIFICATION00/06/TS0238 Protection and control8.1 Motor startingIt is anticipated that the starting of motors will be accomplished with speed controlstarting, soft starting and in some cases direct on line starting. All starting of morecomplicated motors requires special consideration and approval from the Engineer.All starters shall be accommodated in sheet metal unicellular starter boards.The starters shall be:• Provided with changeable fixed and moving contacts andoperating coils.• Provided with arc chutes or magnetic blowouts wherenecessary.• Fitted with auxiliary contacts, integral with the starter.• Provided with interposing relays as required.• Fitted with auto-manual selector switches as required by thecontrol system.• Fitted with motor protection devices.In sections of the plant in which a number of drives are interlocked, or for any otherreasons must operate together, group isolation interlock shall be employed. Thesestarters shall comply with the provisions of the detailed specification set out below.8.2 Incoming circuit breakersWhere specified incoming circuit breakers shall be provided with overcurrentprotection on at least two phases, this protection may be of the thermal or magnetictype or a combination of these types. It should have an Indefinite Minimum Time Lag(IDMTL) type of characteristic and shall be adjustable to permit discrimination withthe back-up protection on starters.In addition, unrestricted earth fault (standby earth fault) protection shall be providedby means of a single element induction pattern IDMTL type relay to be operated fromthe secondary of a current transformer in the neutral of the associated powertransformer. Operation of the restricted earth fault relay shall initiate tripping of thetransformer HV circuit breaker as well as the incoming LT breaker. The relay shouldhave a flush-mounting pattern suitable for a CT having a 1 or 5 A secondary windingand should have tapping at 10 to 40%.8.3 Circuit breakersCircuit breakers shall be as specified on drawings and rated to the fault level specifiedand conforming to appropriate IEC standards. The circuit breaker operatingNORÐURÁL25/05/2004, REV. C1- 11 / 14 -

NORÐURÁLNORDIC ALUMINUMSTANDARD TECHNICAL SPECIFICATION00/06/TS023mechanisms should be of the "Trip Free" type. The performance characteristics of thecircuit breakers under normal and abnormal conditions shall be as stated in therequirements of Class P2 of IEC 60947-2. The short time current duration shall be 1 s.Three-pole circuit breakers shall be provided on the incoming, interconnections or bussection circuits so that the neutral will not be switched. Circuit breakers shall beprovided with a mechanical "on-off" indicator visible from the front of the board.Where circuit breakers are specified to be of the withdrawable manually or electricallyoperated type, they shall be provided with interlocks such that:• Withdrawal of breaker will initiate tripping well before the pluggingcontacts separate.• Access to the breaker cannot be obtained unless it is completelywithdrawn.• Closing of the breaker cannot be effected unless it is in the fullyplugged-in position.The withdrawing mechanism should be screw or lever operated from the front of thepanel and should be so designed that only moderate effort is required to ensuresatisfactory operation.The circuit breaker carriage should be provided with pins or guide rails for aligningthe plugs and sockets before entry is effected.8.4 IsolatorsIsolators shall be provided on the busbar side of all motor starters and may be"on-load" or "off-load" type, but must be electrically interlocked with the associatedmotor starter. The isolators shall be provided with padlocking facilities in the "off"position.8.5 Protection and ControlAs a minimum, each breaker or motor starter compartment shall have the followingfacilities:Thermal protection.Motor overload protection.Possible reset of protection from PLC.Auto restart of motors under defined conditions.Motor control suitable for local and remote manual initiation.Provision for auto-manual control.Status and alarm indications.NORÐURÁL25/05/2004, REV. C1- 12 / 14 -

NORÐURÁLNORDIC ALUMINUMSTANDARD TECHNICAL SPECIFICATION00/06/TS023Apparatus containing internally mounted current transformers must in addition havemetal labels, marked as above, fixed externally in an accessible position.A typical or type-test saturation curve shall be provided in the form of duplicatetransparencies for each design of current transformer supplied against any orderarising out of this enquiry.10 Junction boxesJunction boxes shall be provided and installed in positions indicated on the designdrawings. Junction boxes shall be to a minimum of IP 55 and shall conform to therelevant IEC standards and be complete with terminals and all other devices asindicated on the relevant drawings.11 DrawingsFollowing the installation of the plant, the contractor shall revise the drawings asnecessary to reflect the "as-built" condition, and submit them to the Engineer forapproval. The Contractor shall also provide for approval the following documentation:• General Arrangement of panel or boards showing leading overalldimensions.• Foundation details.• Schematic diagrams of power, control and protection of each circuit.• Wiring diagram of power, control and protection of each circuit.NORÐURÁL25/05/2004, REV. C1- 14 / 14 -

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