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Home / Technical Articles / Good Practice Rules For In-Process Inspection Of Low Voltage Switchboard

Why In-Process Inspection?

The purpose of in-process inspection is to ensure product conformity after each manufacturing operation. This process concerns all the manufacturing operations done by the workshop operators.

Performing In-Process Inspection Of Low Voltage Switchboard In 8 Stages
Performing In-Process Inspection Of Low Voltage Switchboard In 8 Stages

Inspection during the manufacturing stage could be described by the following process: Inspection during the manufacturing stage and Continuous inspection.

Inspection during the manufacturing stage involves carrying out checks at different stages of the assembly process:

Inspections done at the end of each key manufacturing step (enclosure assembly, power busbar, device installation, power connection, auxiliary and low power circuits, labelling and marking final mounting) are part of the operators’ work. Each operator must fill in an “In-process inspection report”.

Quality inspectors have responsibility for overseeing and compiling all “In-process inspection reports”.

Why continuous inspection is necessary?

The assembly operations require constant observance of good practice rules. Due to this, this procedure involves carrying out checks throughout manufacturing in the form of operator or project supervisor checks. It will make them responsible for the quality of their work.

These checks should always be validated by the final inspection inspectors.

Contents:

    1. Switchboard Design
    2. Assembly of enclosures
    3. Power busbars
    4. Installing the devices
    5. Power connections
    6. Auxiliary and low power circuits
    7. Labelling and marking
    8. Final mounting
    9. Packing

1. Switchboard Design

1.1. Switchboard characteristics

  1. Check the protection index required in the project production file.
  2. Check that the corrosion resistance required in the project production file is taken in account.
  3. Check the form partitioning level.
  4. Check the organization of spares.
  5. Make sure that separate equipment delivery is defined.
Switchboard design
Switchboard design

1.2. Cubicle characteristics

  1. Check that the dimensions, number and layout of cubicles are in accordance with the layout and the civil engineering works specified in the project production file.
  2. Check that the incoming cable cut-outs comply with the incoming cables’ characteristics (section number, position).

1.3. Busbar characteristics

  1. Check the environmental installation (temperature, humidity) specifcation required in the project production file.
  2. Check that the horizontal and vertical busbar cross-sections are in accordance with the short-circuit and/or peak current.
  3. Check that busbars are in conformity with the corrosion resistance required in the project production file.
  4. Make sure that the type of busbar coating is defined.

1.4. Device and drawer characteristics

  1. Make sure that device characteristics defned comply with the project production file and derating tables.
  2. Make sure that the jaw characteristics comply with the corrosion resistance.
  3. Check that the mismatch coding is defned.

1.5. Wiring characteristics

    1. Validate the single-line diagram.
    2.  Check that BUS architecture rules are complied with (cf. wiring guide).

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2. Assembly of enclosures

Engineers in production must check if the identification on cubicles matches the project and if the number and type of columns match the drawings. Conformity with front panel drawings is obligatory.

Schneider Electric's OKKEN withdrawable switchgear - Front view
Schneider Electric’s OKKEN withdrawable switchgear – Front view

2.1. Dimensions of cubicle

Check the cubicle dimensions (height, width, length and depth) by measuring and comparing them with those required in the project production fle.


2.2. Mechanical assembly

  1. Check the overall assembly, frame position (top, bottom), bottom plate, mounting plate, etc.
  2. Check that screws are properly tightened.
  3. Check the quality of paint.
  4. Check the degree of protection (quality of washers).
  5. Check bonding continuity (wscews, contact washers…).

2.3. Cleanness

Check the cleanness of the framework assembly: no grease, no scratch, etc.

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3. Power busbars

3.1. Forms

Verify the presence of all screens, form partitioning and protection cover of busbars.


3.2. Type and characteristics

Check the bars’ characteristics according to the type of equipment, the project specifcations and the project design.


3.2.1. Cross-section
  1. According to nominal current (In), short-circuit current and/or peak current, IP, circuit-breaker breaking time, etc.
  2. Check that the cross-section corresponds to that shown in the project production file and product documentation.

3.2.2. Coating

Check the type of busbar coating (bare copper, tin-coated, sheathed busbars, epoxy paint, silver-plating, nickel, etc.).


3.2.3. PE and/or PEN protection busbar characteristics
  1. Cross-section: check using the technical guide.
  2. Presence and cross-section of fishplates between cubicles: check that fishplate cross-section is at least equal to the cross-section of the busbar to be connected (see technical guide).
  3. Earthing systems: in some configurations (earthing systems: TNC, TNS), check presence of the PEN/PE connection.
  4. Two-colour green/yellow marking: check presence of the green/yellow marking and PE or PEN lozenges on the conductors.
  5. Earthing fishplate: check presence and cross-section of fishplate. Then ensure that its cross-section is the same as that of the earth busbar (for PEN).

3.3. Layout and installation

3.3.1. Busbars
  1. Check their position (horizontal, vertical, top, etc).
  2. Check that the layout or arrangement of the busbars does not obstruct the routing of customer cable.
  3. Ensure the extension possibilities of the busbars according to specific features.

3.3.2. Supports
  1. Check the spacing, fastening, characteristics and number of busbar supports. Refer to technical documents, switchboard characteristics, etc.
  2. Type of supports:
    • Check their type and characteristics (material) referring to the switchboard characteristics,
    • Check the correct alignment of supports and the absence of deformation due to extra torque applied to the fixing bolt.

3.4. Bending radius and bar alignment

  1. Check that the bending radius and angle are in accordance with the drawing. If specifed, use the jig to check dimensions.
  2. Check the perfect alignment of the various bar assemblies:
    • Ensure good positioning in the support,
    • Make insertion of the connection bolt easier.
OKKEN switchboard busbars
OKKEN switchboard busbars (photo credit: exceldis.com)

3.5. Busbar junctions and links

  1. Joint cross-sections.
  2. Characteristics and number.
  3. Check positioning and accessibility of the joint screws.
  4. Insulating distances versus frame, form partition, etc.
  5. Bar overlapping surfaces: H = th. x n.
  6. For all non-standard bar connections done under supervision of the fitter, an overlapping height equal to 5 times the thickness of the derived busbar must be allowed for order to obtain a suitable connection.

3.6. Contact surfaces

  1. Quality of drilling/punching and surface finish (no burr or cutting deformations on the conductors, no oil stains, etc.).
  2. Correspondence between the hole diameter and bolt.

3.7. Bolt characteristics

Check the bolt type (in accordance with the product specifications), quality: class 8/8, stainless steel, etc.


3.8. Installation and tightening torque

  1. Bolt insertion method (insulating distance), length of bolt, etc.
  2. Presence, position and type of washer.
  3. Tightening torque in accordance with bolt, devices and other part characteristics. Consult the product and devices documentation.
  4. Presence of varnish certifying tightening to correct torque.
  5. In case of doubt:
    • Number of threads protruding from the nut, for connections of the same type, differs on screws of the same length,
    • Contact washers excessively crushed or moving, carry out a sampling check. If a number of faults are detected, ask the person responsible for assembling the switchboard to verify all its connections.
Installation and tightening torque (example of OKKEN and BLOCKSET switchgears)
Installation and tightening torque (example of OKKEN and BLOCKSET switchgears)

3.9. Clearances

  1. Shortest distance in the air between two live conductors or between live conductors and exposed conductive parts:
    • 14 mm for 12 kV impulse voltage (main MCCB over 1000A busbar),
    • 8 mm for 8 kV impulse voltage (Feeder MCCB up to 1000A),
    • 5.5 mm for 6 kV impulse voltage (MCB).
  2. The IEC 61439-1 and 2 standards stipulate the minimum clearances required to withstand impulse voltage up to 2000 m above sea level.
  3. Pollution degree 3.

3.10. Creepage distances

  1. Shortest distance along an insulated material surface between two live conductors or between live conductors and exposed conductive parts:
    • 16 mm for rated insulation voltage 1000 V AC and DC (main busbar MCCB over 1000A),
    • 12.5 mm for rated insulation voltage 750 V AC and DC (MCCB up to 1000A),
    • 8 mm for rated insulation voltage 500 V AC and DC (MCB).
  2. See IEC 61439-1 and 2 table 2.
  3. Pollution degree 3, Material group 3a

3.11. Marking and phase order

  1. Check phase labelling type conformity.
  2. Check that phase order (phases 1, 2, 3, neutral and PE) is complied with according to the product specifcations.
Busbar phase order marking
Busbar phase order marking

3.12. Cleanness

  1. After busbar installation, ensure that no foreign bodies are lost in the bars compartment.
  2. In particular in the case of access difficulties.

3.13. Checking technical data

3.13.1. Toroids

Check the technical data of each toroid. Also ensure the correct mounting direction: the arrow shows the current direction.

Toroid transformer - technical data
Toroid transformer – technical data
3.13.2. Current transformer
  1. Check the technical data of the current transformers together with the installation direction.
  2. Check the correspondence between the current transformer and the associated device, ammeter, etc.
    Ensure that the current delivered by its secondary circuit is compatible with the associated device.
  3. Check compliance with clearances between the fastenings and the secondary connecting screws of the current transformer relative to live conductors or metal parts.
  4. Check whether the current transformers are well secured on the conductor.

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4. Installing the devices


4.1. Conformity of devices

4.1.1 Device characteristics
  1. Type, rating.
  2. Breaking capacity and number of poles.
  3. MCCB (over 1000A) terminal pad characteristics and installation (according to product). Inspection to be performed prior to installation in the cubicle.

4.1.2. Toroids

Check the technical data of each toroid. Also ensure the correct mounting direction: the arrow shows the current direction.


4.1.3. Current transformer
  1. Check the technical data of the current transformers together with the installation direction.
  2. Check the correspondence between the current transformer and the associated device, ammeter, etc. Ensure that the current delivered by its secondary circuit is compatible with the associated device.
  3. Check compliance with clearances between the fastenings and the secondary connecting screws of the current transformer relative to live conductors or metal parts.
  4. Check whether the current transformers are well secured on the conductor.

4.1.4. Shunt

Check the connection between the shunt and the measuring instrument.


4.1.5. Safety perimeters
  1. Check the circuit-breaker safety perimeters, referring to their installation guides.
  2. No devices, equipment or bundles should be located in the safety perimeter.

4.2 Mounting

4.2.1. Contact surfaces
  1. Quality of drillings or punching and surface finish (no burr or cutting deformations on the conductors, no oil stains, etc.).
  2. Correspondence between the hole diameter and bolt.
  3. Bar overlapping surfaces: H = th. x n.
  4. For all the non-standard bar connections done under supervision of the fitter, an overlapping height equal to 5 times the thickness of the derived busbar must be allowed for in order to obtain a suitable connection.
  5. Avoid problems (flexion, torsion, etc.) due to incorrect busbar positioning on devices or terminal pad connections.
Contact surfaces
Contact surfaces
4.2.2. Bolt characteristics

Check the bolt type (in accordance with the product specifcations), quality: class 8/8, stainless steel, etc.


4.2.3. Installation and tightening torque
  1. Bolt insertion method (insulating distance), length of bolt, etc.
  2. Check the vertical busbar sliding bolt position.
  3. Presence, position and type of washer.
  4. Tightening torque in accordance with bolt, devices and other parts’ characteristics. Consult the product and devices documentation.
  5. Presence of varnish certifying tightening to the correct torque.
  6. In case of doubt:
    • Number of threads protruding from the nut, for connections of the same type, differs on screws of the same length,
    • Contact washers excessively crushed or moving, carry out a sampling check.

If a number of faults are detected, ask the person responsible for assembling the switchboard to verify all the connections.

Installation and tightening torque
Installation and tightening torque
4.2.4. Clearances
  1. Shortest distance in the air between two live conductors or between live conductors and exposed conductive parts:
    • 14 mm for 12 kV impulse voltage (main busbar MCCB over 1000A),
    • 8 mm for 8 kV impulse voltage (MCCB up to 1000A),
    • 5.5 mm for 6 kV impulse voltage (MCB).
  2. The IEC 61439-1 and 2 standards stipulate the minimum clearances required to withstand impulse voltage up to 2000 m above sea level.
  3. Pollution degree 3.
Shortest distance in the air between two live conductors or between live conductors and exposed conductive parts
Shortest distance in the air between two live conductors or between live conductors and exposed conductive parts
4.2.5. Creepage distances
  1. Shortest distance along an insulated material surface between two live conductors or between live conductors and exposed conductive parts:
    • 16 mm for rated insulation voltage 1000 V AC and DC (main busbar MCCB over 1000A busbar),
    • 12.5 mm for rated insulation voltage 750 V AC and DC (MCCB up to 1000A),
    • 8 mm for rated insulation voltage 500 V AC and DC (MCB).
  2. See IEC 61439-1 and 2 Table 2.
  3. Pollution degree 3, Material group 3a.
Shortest distance along an insulated material surface between two live conductors or between live conductors and exposed conductive parts
Shortest distance along an insulated material surface between two live conductors or between live conductors and exposed conductive parts

4.3. Test

The use of drawer test equipment is recommended for the mechanical and electrical testing of each drawer.


4.3.1. Manual operation of equipment
  1. Manoeuvre the manual mechanisms of the devices, to ensure their proper operation.
  2. Check the operation of the functional units based on drawers, disconnectable, plug-in on base or chassis version.

4.3.2. Equipment fastening
  1. Check the fastening of the devices on the drawers, on Polyfast (inspection during manufacturing process), on mounting plates, on doors, etc.
  2. Check that they are correctly fitted and that all the necessary screws or miscellaneous additional items are present.
  3. Special attention should be paid to:
    1. Assembly compliance with functional dimension tolerances,
    2. Jaw installation and validation in the check list,
    3. Check that the auxiliary blocks are correctly identified and assembled and that the mechanical assemblies remain free to move.


4.3.3. Mechanical operation

To be checked:

  1. Installation and operations of the position contact, door, drawer position, extended rotary handle, etc.,
  2. Operation of the limit switch, position of drawers, circuit breakers, contact located on door,
  3. Functional units (drawers – plug-in, disconnectable, etc.) operating margin.
OKKEN drawer
OKKEN drawer
4.3.4. Jaws

Check power jaws plug-in penetrations and installation.

Withdrawable cassette
Withdrawable cassette (drawer)
4.3.5. Accessibility of functional units or devices
  1. Check accessibility of the terminal, current transformer, etc.
  2. Always check the ease of access to pivoting front face locking devices.
  3. If stipulated in the project specifications, check also check the access facilities for thermography.

4.3.6. Degree of protection
  1. This check is performed by verifying that the components ensuring the IP rating stated in the project production fle are indeed present.
  2. Needs vary according to the required IP rating: awning, seal, front plate, cable glands, etc. (information given in the product catalogues or guides).
  3. If a seal is used, ensure it is properly positioned and continuous.
  4. Verify that the IP rating of the equipment located on the door or the device manoeuvring mode (apertures on doors or presence of specific cover), matches switchboard requirements.

4.3.7. Safety check

Ensure that no foreign body remains in the bar compartment.

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5. Power connections

5.1. Wiring

To be checked according to the device and switchboard characteristics.


5.1.1. Flexible bar characteristics and installation
  1. Check characteristics and cross-section.
  2. Radius of curvature of the flexible bars (at least once times bar thickness). Manual bending operations are recommended to avoid damaging the bar insulator.
  3. In the event of a superimposed flexible bar installation, ensure that insulating spacers are placed between the conductors to provide proper ventilation.
Flexible bar installation
Flexible bar installation
5.1.2. Binding and cable trunking
  1. Check that the characteristics and number of bindings used match the electro-dynamic force that could affect the assembly in case of short circuit.
  2. No direct binding on metal parts. If necessary ft an insulating wedge.
  3. Check connections: presence of thick flat washer and contact washer.
  4. Maximum cable size 6 mm2 in cable trunking:
    1. Ensure that the spare space in the cable trunking is approximately 30 %. Cable fasteners should preferably be made of insulating accessories (e.g. polycarbonate screws or rivets),
    2. The maximum centre-to-centre distance between two trunking fasteners must not exceed 600 mm.

5.1.3. Cable characteristics
  1. Cross-section of power and auxiliary conductors: check cross-sections with reference to the switchboard specifications and product documentation.
  2. Type and colours.
  3. Nature of cables: Schneider recommends use of U 1000 V insulation with an insulation temperature resistance of < 105°C (self-extinguishing).
  4. Using these cables, we meet class 2 requirements, so these cables may be secured directly on metal supports.

5.1.4. Cables installation
  1. Protection of cables:
    1. Check that the cables do not run near sharp edges, moving parts, against or between exposed live parts, air blast areas, etc.,
    2. No cables should be inserted in ventilation grille hole or mechanical fixing holes.
  2. Radius of curvature: ensure that the cable radius of curvature is roughly 6 to 8 times cable diameter.
  3. Number of cables per strand
  4. Separating the strands: check that the power and control strands are separated as well as the strands receiving an auxiliary voltage of more than 500 V AC and the DC circuit and communication network.
  5. Cable fixing: make sure that the conductors are fastened in accordance with their characteristics, size and network short circuit withstand. Check collar characteristics.
  6. Non-protected active conductors:
    1. Ensure that cables not protected by short-circuit devices are installed safely along their entire path,
    2. Separated bundle, no risk of mechanical damage, safe connection, etc.

5.1.5. Cable connections

Three types of inspection are performed according to the connections:

  1. Visual inspection (A) of:
    • The crimping recess (quality, pressure, etc.),
    • The correspondence between the lug or terminal and the cable section;
    • The position of the conductor core in the lug shaft, and proper cable insertion,
    • The bolt diameter relative to the lug fxing hole,
    • The quality of the cable insulation and strands (no damage during cable installation or wire stripping operation).
  2. Mechanical inspection (B) by manual pulling (performed by random sampling).
  3. Verifcation (C) of:
    • Presence and direction of contact washers,
    • Presence of varnish certifying tightening to the right torque (on visible connections) or use of torque nuts.

The following table gives the inspections to be performed according to the type of connection used (where A, B, C stand for the various inspection types: A = visual inspection, B = mechanical inspection, C = checking presence and positioning)

ConnectionsPowerOther circuits
Jaws and auxiliaries pinsA+BA+B
LugsA+CB+C
ClipsA+B
Cable connectorsAB
TerminalsB+CB
ScrewsCC

Connection stresses and fastening:

  • Check that the lugs match with the connector type,
  • Be sure that the cables are properly inserted in the terminal,
  • Reminder: make sure that the crimping tools are calibrated
Cable connections
Cable connections

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6. Auxiliary and low power circuits


6.1. Wiring (terminal blocks and protection busbar connection)

6.1.1. Bolt characteristics and tightening torque
  1. Check the bolt type (in accordance with the product specifications), quality: class 8/8, stainless steel, etc.
  2. Bolt insertion method (insulating distance), length of bolt, etc.
  3. Check the vertical distribution busbar sliding bolt position.
  4. Presence, position and type of washer.
  5. Presence of varnish certifying tightening to the correct torque.
  6. Check that all screws, picot washers and earth braids (if required) for fixing these components are present.
  7. In case of doubt:
    1. Number of threads protruding from the nut, for connections of the same type, differing on screws of the same length,
    2. Contact washers excessively crushed or loose: carry out a random check.
If a number of faults are detected, ask the person responsible for assembling it to verify all the switchboard connections.

6.1.2. Cable characteristics
  1. Check cross-section of power and auxiliary conductors: check cross-section with reference to the switchboard specifications and product documentation.
  2. Type and colours.
  3. Nature of cables: Schneider recommends use of U 1000 V insulation with an insulation temperature resistance of < 105°C (self-extinguishing).
  4. Using these cables, we meet class 2 requirements, so these cables may be secured directly on metal supports.

6.1.3. Cable installation
  1. Protection of cables:
    1. Check that the cables do not run near sharp edges, moving parts, against or between exposed live parts, air blast areas, etc.,
    2. No cables should be inserted in ventilation grille holes or mechanical fixing holes.
  2. Radius of curvature: ensure that the cable radius of curvature is roughly 6 to 8 times cable diameter.
  3. Number of cables per strand
  4. Separating the strands: check that the power and control strands are separated as well as the strands receiving an auxiliary voltage of more than 500 V AC and the DC circuit and communication network.
  5. Cable fixing: make sure that the conductors are fastened in accordance with their characteristics, size and network short circuit withstand. Check collar characteristics.
  6. Wiring in cable trunking:
    1. Maximum cable size 6 mm² in cable trunking,
    2. Ensure that the spare space in the cable trunking is approximately 30 %; cable fasteners should preferably be made of insulating accessories (e.g. polycarbonate screws or rivets),
    3. The maximum centre-to-centre distance between two trunking fasteners must not exceed 600 mm.
  7. Non-protected active conductors:
    1. Ensure that cables not protected by short-circuit devices are installed safely along their entire path,
    2. Separated bundle, no risk of mechanical damage, safe connection, etc.
  8. Accessibility and client connection facilities: Accessibility of power connection points on devices, and terminal blocks:
    1. Compliance with the cable curvature radius and cable routing (entry from the top/bottom),
    2. Check the length of pads and number of connecting holes taking into account the size and number of cables (check the devices or product information).
  9. Check that the number and cross-section of cables ensure compliance with clearances (lugs).
Cable glands are used to protect cables from the hole in the sheet
Cable glands are used to protect cables from the hole in the sheet

Cables fixing tip
Cables fixing tip

Cable installation mistake
Cable installation mistake

Reminder: – The arrange must ensure safety of the operators (maintenance);

  1. The number and sturdiness of cable supports,
  2. The ease of connection of client cable on earth or PEN bar nearby the functional unit

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7. Labelling and marking

  1. Marking and identifcation of the assembly:
    1. IEC 61439-1 & 2 standards require that the assembly must be identified with specific information,
    2. Name of the assembly manufacturer.
  2. Marking of devices, pushbuttons, indicators, etc.
  3. Marking of conductors (control and power)
  4. Quality of labels and their attachment
  5. Instruction and warning labels
  6. Marking of wires and customer connection terminals.

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8. Final mounting

8.1. PE and/or PEN protection busbar characteristics

  1. Cross-section: check using the technical guide.
  2. Presence and cross-section of fishplates between cubicles: check that fishplate cross-section is at least equal to the cross-section of the busbar to be connected.
  3. Earthing systems: in some configurations (earthing systems: TNC, TNS), check presence of the PEN/PE connection.
  4. Two-colour green/yellow marking: check presence of the green/yellow marking and PE or PEN lozenges on the conductors.
  5. Earthing fishplate: check presence and cross-section of fishplate. Then ensure that its cross-section is the same as that of the earth busbar (for PEN).

8.2. Appearance (Paint colour and reference)

  1. Use the colour palette to ensure that the reference of the paint given in the project file matches the colour of the cubicle.
  2. Verifcation generally carried out at the incoming delivery inspection stage.

8.3. Mounting

8.3.1. Panelling
  1. Operation of drawers:
    1. Check the operating safety margin of the drawers and ease of operation; drawer inserting and withdrawal should be performed without damaging the internal components or wiring.
  2. Operation of doors and mechanical accessories:
    1. Check their operation by manoeuvring them,
    2. Ensure that the cubicle equipment is complete and has been installed properly.
  3. Check the presence, characteristics (IP, material, etc.) and proper fitting of:
    1. Ventilation grille, bottom plate,
    2. Side and rear cover,
    3. Roof, blanking plate, etc.
  4. Conformity of apertures in the plates: using the drawing, check the presence of any apertures in the roofs, mounting plates and separation plates allowing fish plating, coupling bar installation, interlock cable or rod installation, etc.
OKKEN switchgeaar
OKKEN switchgeaar
8.3.2. Degree of protection
  1. This check is performed by checking the presence of the components ensuring the IP level stated in the project production file.
  2. Needs vary according to the required IP degree: awning, seal, front plate, cable glands, etc. (information given in the product catalogues or guides).
  3. If a seal is used, ensure it is properly positioned and continuous.
  4. Make sure that the IP degree of the equipment located on the door or the device manoeuvring mode (apertures on doors or presence of specific cover), matches the switchboard requirements.

8.3.3. Safety check

Ensure that no foreign body is lost in the bar compartment.

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9. Packing

9.1. Cleanness

Prior to packing, check that the equipment is clean:

  1. No dust,
  2. No foreign body forgotten in the equipment.

9.2. Miscellaneous

Using a detailed check list established by the design office, perform inspection of:

  1. All the equipment to be delivered separately, spare parts, devices dismantled for transport, etc.,
  2. Roof, coupling screws,
  3. Busbar joints, etc.

9.3. Documentation

  1. Presence of the name plate and/or the “as built design“.
  2. Make sure that all the documentation relating to the quality inspection procedures are filled in:
    1. Missing parts list,
    2. Quality control plan,
    3. Checking program,
    4. Corrective action form,
    5. Non-quality record board,
    6. Delivery slip, etc.
  3. Associated documentation delivered with the equipment:
    1. Device and switchboard technical documentation,
    2. Maintenance documentation,
    3. Missing parts list, and on request,
    4. Quality control plan.
  4. Be sure that all internal devices and other parts are well secured, inserted or locked in the switchboard.

9.4. Packaging

Inspection of packaging before delivery according to:

  1. The type of product to be carried,
  2. The means of transport,
  3. The destination,
  4. Storage conditions,
  5. Climatic conditions
LV switchgear packing
LV switchgear packing

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Reference // Low voltage switchboards Quality inspection guide – Schneider Electric

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author-pic

Edvard Csanyi

Electrical engineer, programmer and founder of EEP. Highly specialized for design of LV/MV switchgears and LV high power busbar trunking (<6300A) in power substations, commercial buildings and industry facilities. Professional in AutoCAD programming.

6 Comments


  1. Aldo da Rin
    Oct 24, 2019

    Nice and complete article. Can you pass on information regarding low voltage terminations and associated international rules? I have noted several standards: with/without “heat-retractable sleeve” to seal main insulation layer when it is split apart, what kind of terminal lug, how to connect screen, if present, on power cables, how to connect inverter power cables to switchboard, etc.

    Thanks in advance.


  2. Mickey Mc Carron
    Apr 24, 2019

    This article is very informative and may I ask 1 question.

    Is it good practice to fix CT’s to the panel frame work as opposed to having them loose on the conductor or secured to the conductor utilising a cable tie. The CT’s in question are being installed on a 400 amp supply to a LV Panel Board, parallel 4 core 150mm swa cable.
    Please advise.
    Thank You


  3. Salem A Bahakim
    Mar 24, 2018

    It is very useful
    can you allow dawn loading it


  4. SUNIL KARANDIKAR
    Mar 22, 2018

    The article is very well written; it is informative and a handy reference. I wish that aluminium bus bars also also covered. Whether fasteners (bolts & nuts) should always be of stainless steel?


  5. Jovan Milošević
    Mar 22, 2018

    Thank you for this nice reminder


  6. scott davis
    Mar 21, 2018

    Thank you. It helped my inspection staff to see the level of detail that happens at the factory and by factory-trained technicians. We must do a visual-only inspection of the installed electrical equipment. Our observations may well be keener after reading your online offering.

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