PART 1 - GENERAL
1.01 DESCRIPTION
A. This section covers the manufacture, furnish, installation and testing of all equipment, accessories and materials required for the installation of LV Switchboards (Type Tested Assemblies) in accordance with the specifications and drawings.
1.02 APPLICABLE CODES AND STANDARDS
A. The work shall be carried out in accordance with this specification, the contract drawings and the standards listed hereunder.
The following codes and standards provide an acceptable level of quality for materials and products:
1. SASO 1609 Saudi Standard for low voltage switchgear and controlgear
assemblies-Part 1 : Type tested and partially type tested assemblies
2. IEC 60439-1 Low voltage switchgear and controlgear assemblies-
Part 1 : Type tested and partially type tested assemblies
3. IEC 60529 Degrees of protection provided by enclosure (IP Code)
1.03 QUALITY ASSURANCE
A. All materials and products shall be new, sound and uniform in quality, size, shape, color and texture and shall be free from defects.
B. The contractor shall be responsible for ensuring that the required standards of quality control as mentioned in relative sections are maintained for the proposed switchboards.
C. If requested by the Ministry, the supplier shall provide proof of application of a quality procedure complying with standards. This means:
1. use of a quality manual approved and signed by a management representative,
2. regular updating of this manual so that it reflects the most recent applicable quality control procedures,
3. ISO 9002 certification.
D. The manufacturer must have a sound experience in the field of LV switchboards for not less than ten years, and should have a presentable reference list of the already supplied equipment of the same type and same make and that this equipment has been in satisfactory operation in Kingdom of Saudi Arabia for at least five years.
1.04 SUBMITTAL
A. Shop Drawings and Manufacturer's Data:
The contractor shall submit to the Ministry representative for review, detailed dimensioned shop drawings and manufacturer's literature where deviations from the contract drawings or specification exist. Shop drawings and/or data sheets shall be based on information stated in the specifications and as shown on the contract drawings and shall show all pertinent deviations and data for the fabrication and complete installation.
Manufacturer's data sheets shall be submitted indicating the necessary installation dimensions, weights, materials and performance information. The above information may be provided by standard catalogue sheets marked to indicate the specific items provided.
B. Operation and Maintenance Instructions:
The contractor shall furnish data covering model, type and serial numbers, capacities, maintenance and operation of each major item of equipment or apparatus in accordance with the requirements of the contract documents. Operating instructions shall cover all phases of control.
C. Test Reports:
The contractor shall submit test reports to the Ministry representative for review.
D. Recommended Spare Parts List:
The contractor shall submit recommended spare parts list to the Ministry representative for review.
E. As Built Drawings:
The contractor shall submit the as built drawings to the Ministry representative for review and approval.
1.05 COORDINATION
A. The contractor shall be held responsible for the proper coordination of all phases of the work under this contract.
B. It shall be the responsibility of the contractor to coordinate the work and equipment as specified herein with work to be performed and equipment to be furnished under other sections of the specifications in order to assure a complete and satisfactory installation.
1.06 PRODUCT DELIVERY, STORAGE AND HANDLING
A. Deliver, store, protect and handle products to site as per manufacturer’s instructions.
B. Store swithboards in clean and dry space. Inspect for damage. Maintain factory wrapping or provide an additional heavy canvas or heavy plastic cover to protect units from dirt, water, construction debris and traffic.
C. Lift only with lugs provided for the purpose. Handle carfully to avoid damage to switchboard internal components, enclosure and finish.
PART 2 - PRODUCTION
2.01 GENERAL
A. The following specifications apply to LV Switchboards rated above 250 Amps and upto 4000 Amps, classified as ‘Main Distribution Boards’ and ‘Sub-Main Distribution Boards’.
B. Extensions to the low voltage electrical switchboards shall be possible on either side (right or left).
C. The Switchboard and the associated Switchgear and Controlgear like Circuit Breakers, Contactors, Switches, Meters etc. should be from the same manufacturer.
2.02 TECHNICAL CHARACTERISTIC
A. The switchboards shall be designed and tested for the following electrical values:
1. Rated voltage 1000 V three-phase.
2. Rated operating voltage 690V
3. Frequency 60 Hz.
4. Insulation level 2.5 kV- 60 Hz, 1min
8 kV-1,2/50µs.
5. Busbar rated current As shown on the drawings.
6. Short-circuit withstand current As shown on the drawings.
7. Degree of protection (IP) IP 31 for Indoor Application and IP55 for Outdoor
Application or as indicated on the drawings
8 Impact strength (IK) IK08 for Indoor Application and IK10 for Outdoor Application.
2.03 SERVICE CONDITIONS
A. The switchboard shall be suitable for operations at a height of less than 2000 meters above sea level.
B. The switchboards shall be capable of operating normally within the following temperature range
1. Maximum air temperature + 40 ° C
2. Minimum air temperature - 5 ° C
C. Manufacturer shall declare wether switchboard is able to operate in air temperature higher than + 40 °C and if current derating is necessary.
2.04 CONSTRUCTION AND OPERATION
A. The low voltage switchboard shall have a permissible asymmetrical short circuit current up to short circuit current shown on the drawings for 1 second. The busbars shall be designed for mounting on insulated supports that are sufficient in number to accept the electro-dynamic forces resulting from the flow of the peak asymmetrical short circuit current.
B. The low voltage switchboard shall have an earthing circuit including a bar that can be removed for isolation purposes during the necessary insulation measurements (removal of the bar shall require a tool)
C. The switchboard shall be suitable for front or rear connections.
D. Cable entry shall be via the bottom or the top.
E. The low voltage switchboard shall not be heigher than 2000mm.
F. Natural ventilation shall make it possible for the Switchboard components to operate with in the recommended temperature ranges.
G. The low voltage electrical switchboard shall have small depths, thus optimizing layout in electrical rooms:
1. Max. 400 mm up to 1600A.
2. Max.1200 mm up to 4000 A.
H. The system shall make it possible to implement fixed or withdrawable distribution switchgear.
I. Selection of switchboard components shall be made in compliance with standard IEC 60947 and related specification in the contract documents.
J. The low voltage electrical switchboard shall be made up of identified functional volumes including the busbar compartment, switchgear and controlgear component compartment, connection compartment and auxiliaries compartment.
1. The different types of busbars shall be the main busbars, distribution busbars and auxiliary busbars.
2. The busbars shall be made of electrolytic copper.
3. The compartment shall be located inside a metal enclosure with walls providing protection against direct contact with live parts and guaranteeing a degree of protection (IP) requested. The frame, the external panels (doors, side and rear panels, tops) and internal elements (ducts) shall be made of 1.5-mm thick folded metal steel sheet and protected by epoxy polyester powder paint coating.
K. Withdrawable circuit breakers shall have four different positions:
1. Connected
2. Test
3. Disconnected
4. Removed
L. The switchboard shall be suitable for installation side by side and back to back and capable of receiving lateral ducts for busbar, cables and terminals.
M. The switchboard cover panel shall be removable.
N. The construction system shall provide a complete set of elements for installing fixed or withdrawable switching and protective devices, measurement devices and control/ monitoring devices in the switchboard.
2.05 Protection and safety
A. The low voltage electrical switchboards shall ensure the safety of life and property as well as provide a high level of continuity to service
1. Switching safety shall be ensured by mechanical device preventing on load withdrawal
2. Operating safety shall be ensured by compartmenting in compliance with standard IEC 60439-1 and according to Form 2b. However, if specifically asked, the same Switchboard should be capable of upgrading to Form 3a, 3b, 4a or 4b.
3. Current interruption shall be of the “ visible break isolation “or “positive contact indication “type as defined by standard IEC 60947-3.
B. In view of reducing the risk of electrical shock
1. Power and control circuit shall be separate and completely isolated.
2. Auxiliary circuits shall be of the extra low voltage type.
2.06 TYPE TESTS AND ROUTINE TESTS
A. Routine Tests
The switchboard shall be subject to Routine Factory Test carried out by the Panelbuilder and shall be substantiated by a test report signed by the factory quality control department., in accordance with IEC 60439 –1 as follows:
1. Conformity with drawings and diagrams.
2. Visual Inspection.
3. Functional electrical and mechanical operation
4. Dielectric test.
B. Type Tests
In accordance with IEC 60439 –1, the Switchboard Design must have qualified fully to the Seven Type-Tests detailed below, conducted by an Accredited Independent Testing Laboratory like ASEFA, ASTA, KEMA etc. Certificates for each Test shall be submitted to the Ministry Representative for Review.
1. Temperature-rise test.
2. Dielectric test.
3. Short-circuit withstand test.
4. Effectiveness of the protective circuits test.
5. Clearance and creepage distance test.
6. Mechanical operation test.
7. Degree of protection test.
PART 3 - EXECUTION
3.01 WORKMANSHIP
A. Materials, products and equipment furnished by the contractor, shall be installed and all work shall be performed in a first-class workmanship manner, in conformity with the best trade practices and the printed directions of the applicable manufacturers; by skilled workers equipped to produce satisfactory results; in a safe, substantial manner so as to avoid undue stresses, rigid enough to prevent undue movement, so as to present a neat, orderly appearance and to facilitate operating, servicing, maintenance and repairing.
3.02 FOUNDATIONS AND SUPPORTS
A. The contractor shall provide concrete pedestals, anchor bolts, hangers, channels, saddles, etc., for installation of equipment and apparatus shown on the drawings and specified in the various sections.
3.03 EQUIPMENT INSTALLATION
A. All electrical equipment shall be installed in accordance with the manufacturer's recommendations, good electrical engineering practice, and the relevant drawings and specifications.
B. All metal surfaces to be bolted shall be thoroughly cleaned before assembly. The connections shall be tightened with manual torque wrenches to the manufacturer's erection instructions.
C. Splices shall be implemented to ensure the electrical continuity of the horizontal busbars, auxiliary buses and the proactive conductor between adjacent sections.
D. It shall be possible to secure the sections to a floor that is flat by nchoring directly to a concrete floor using anchor bolts or by securing to ordinary metal profiles.
3.04 EQUIPMENT TESTING AND COMMISSIONING
A. After the installation is complete and properly adjusted, the contractor shall conduct operating tests. The various equipment and systems shall be demonstrated to operate in accordance with the requirements of the contract documents. Tests shall be performed in the presence of the client/client representative. The contractor shall provide electric power, instruments and personnel necessary for performing the various tests.
B. The testing of all electrical equipment shall include, but not be limited to, the items below. This shall be in addition to testing specified elsewhere in this specification.
1. General equipment check.
2. Field wiring and ground system verification.
3. Equipment adjustment.
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