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Main Types of Cable Tests

Cable testing is the process of checking that an electrical cable meets the required quality, safety, and performance standards before it is delivered to the customer. It verifies the cable's electrical, mechanical, and physical properties according to standards such as IEC, BS, ASTM, UL, or VDE.

Main Types of Cable Tests

1. Conductor Resistance Test

• Purpose: Check conductor resistance.
• Standard: IEC 60228
• Equipment: Micro-ohmmeter / DC Resistance Tester
• Unit: Ω/km (Ohm per kilometer)

2. High Voltage (HV) Test

• Purpose: Verify insulation can withstand high voltage.
• Standard: IEC 60502, IEC 60227
• Equipment: AC/DC High Voltage Tester

3. Insulation Resistance (IR) Test

• Purpose: Measure insulation quality.
• Equipment: Megger (500V, 1000V, 2500V, or 5000V)
• Unit: MΩ or GΩ

4. Spark Test (Online)

• Purpose: Detect pinholes or insulation defects during extrusion.
• Equipment: Spark Tester

5. Diameter Measurement

• Purpose: Verify insulation and sheath diameter.
• Equipment: Digital Vernier Caliper / Laser Gauge

6. Insulation Thickness Test

• Purpose: Check minimum and average insulation thickness.
• Equipment: Digital Microscope / Projection Microscope

7. Sheath Thickness Test

• Measure PVC, PE, LSZH, or other outer sheath thickness.

8. Tensile Strength & Elongation Test

• Purpose: Check mechanical strength of insulation and sheath.
• Equipment: Universal Testing Machine (UTM)

9. Hot Set Test (XLPE)

• Confirms proper XLPE cross-linking.

10. Hot Deformation Test

• Evaluates deformation of thermoplastic insulation at elevated temperatures.

11. Shrinkage Test

• Measures insulation or sheath shrinkage after heating.

12. Water Absorption Test

• Checks moisture absorption characteristics.

13. Ageing Test

• Evaluates performance after accelerated heat ageing.

14. Flame Test

• Determines flame-retardant performance.
• Standards include IEC 60332 series.

15. Smoke Density Test

• Used for LSZH cables.
• Standard: IEC 61034.

16. Halogen Acid Gas Test

• Measures halogen gas emission.
• Standard: IEC 60754.

17. Partial Discharge Test

• Mainly for medium- and high-voltage cables.
• Detects internal insulation defects.

18. Capacitance Test

• Measures cable capacitance.
• Important for communication and MV cables.

19. Dielectric Loss (Tan Delta) Test

• Evaluates insulation condition in MV/HV cables.

20. Continuity Test

• Confirms conductor continuity from one end to the other.

Common Cable Testing Equipment

• DC Resistance Tester
• Digital Micro-ohmmeter
• High Voltage Tester (Hipot)
• Megger (Insulation Resistance Tester)
• Spark Tester
• Universal Testing Machine (UTM)
• Hot Set Test Apparatus
• Tensile Tester
• Digital Vernier Caliper
• Laser Diameter Gauge
• Projection Microscope
• Oven (Ageing Test)
• Partial Discharge Test System
• Capacitance & Tan Delta Tester

Routine Tests (Factory)

• Conductor Resistance
• High Voltage Test
• Spark Test
• Insulation Resistance
• Visual Inspection
• Diameter Check

Sample Tests

• Tensile Strength
• Elongation
• Thickness Measurement
• Hot Set
• Shrinkage
• Ageing

Type Tests

• Flame Test
• Smoke Density
• Halogen Test
• Short Circuit Test
• Bending Test
• Impact Test
• Water Penetration Test

If you work in an electrical cable manufacturing plant, these tests are typically performed in the Quality Control (QC) Laboratory to ensure every cable complies with the applicable standard before dispatch.

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Drum Capacity Calculator

Drum Capacity Calculator

Cable Diameter (mm)

MAX CAPACITY PER DRUM	Feet	Inch Size

 

Sheathing in Electrical Cable Manufacturing

 Sheathing in Electrical Cable Manufacturing

Sheathing (also called the Outer Sheath or Jacket) is the outermost protective layer of an electrical cable. It protects the cable from mechanical damage, moisture, chemicals, sunlight (UV), abrasion, oil, and environmental conditions.

Functions of Cable Sheathing

• Protects the cable from mechanical damage
• Provides resistance to moisture and water
• Protects against chemicals, oils, and acids
• Offers UV and weather resistance (when required)
• Improves flame retardancy and fire performance
• Increases the cable's service life
• Identifies the cable by its color and printed markings

Common Sheathing Materials

Material	Properties	Typical Applications
PVC (Polyvinyl Chloride)	Economical, flexible, flame retardant	General power and control cables
PE (Polyethylene)	Excellent moisture and UV resistance	Outdoor and underground cables
XLPE	Rarely used as an outer sheath; mainly used for insulation	Special applications
LSZH (Low Smoke Zero Halogen)	Low smoke, halogen-free	Buildings, tunnels, hospitals, airports
TPU	High abrasion and oil resistance	Industrial and mining cables
Rubber (EPR/CSP/Neoprene)	Flexible and weather resistant	Flexible and heavy-duty cables

Sheathing Process

1. Cable core is prepared.
2. Cable passes through an extruder.
3. Sheathing compound is melted.
4. Material is extruded uniformly around the cable.
5. The cable passes through a cooling water trough.
6. Diameter, spark test (if applicable), and surface quality are checked.
7. The cable is printed, wound, and packed.

Quality Tests

• Outer diameter (OD)
• Sheath thickness
• Tensile strength
• Elongation at break
• Spark test (where applicable)
• Hot deformation
• Abrasion resistance
• Flame test
• Aging test

Relevant Standards

• IEC 60502-1 – Power cables up to 1 kV
• IEC 60502-2 – Power cables from 6 kV to 30 kV
• IEC 60811 – Test methods for insulating and sheathing materials
• IEC 60332 – Flame propagation tests
• IEC 60754 – Halogen acid gas tests
• IEC 61034 – Smoke density tests

Example Cable Construction

• Conductor
• Insulation (PVC/XLPE)
• Inner Covering (Bedding)
• Armour (SWA/AWA, if required)
• Outer Sheath (PVC/PE/LSZH)

Example Marking

Cu/XLPE/PVC/SWA/PVC

• Cu – Copper conductor
• XLPE – Insulation
• PVC – Inner covering (where applicable)
• SWA – Steel Wire Armour
• PVC – Outer sheath

Note: The sheath is not an electrical insulation layer. Its primary purpose is mechanical and environmental protection, while the insulation around the conductor provides electrical isolation.

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Cable Insulation Calculator

Cable Insulation Calculator

Standard IEC 60502-1 IEC 60502-2

Voltage 300/500 V 450/750 V 0.6/1 kV 1.8/3 kV 3.6/6 kV 6/10 kV 8.7/15 kV 12/20 kV 18/30 kV 21/35 kV

Conductor Size (mm²)

Conductor Diameter (mm)

Standard

-

Voltage

-

Thickness

-

Overall Dia

-

Types of Screening

Types of Screening in Cable Manufacturing

Screening (shielding) is provided to control the electric field, reduce electromagnetic interference (EMI), and provide a path for fault current.

1. Copper Tape Screening (CTS)

• Metallic screen made of copper tape.
• Applied helically or longitudinally.
• Used in MV and some HV cables.
• Provides shielding and fault current path.

2. Copper Wire Screening (CWS)

• Consists of annealed copper wires around the insulation.
• Higher short-circuit current capacity than copper tape.
• Common in MV and HV power cables.

3. Copper Wire and Tape Screen (CWTS)

• Combination of copper wires and copper tape.
• Improves screen continuity and fault current capacity.
• Widely used in XLPE power cables.

4. Aluminium Foil Screening (AFS)

• Polyester-backed aluminium foil wrapped around conductors.
• Excellent protection against EMI.
• Used in instrumentation and communication cables.

5. Copper Braid Screening (CBS)

• Braided copper wires surrounding the core.
• Flexible and provides good shielding.
• Used in control, instrumentation, and data cables.

6. Individual Pair Screening (IPS)

• Each pair is separately screened with foil or braid.
• Minimizes crosstalk between pairs.
• Used in instrumentation and communication cables.

7. Overall Screening (OS)

• One common screen around all cores.
• May consist of foil, braid, or tape.
• Used in multi-core control and instrumentation cables.

8. Semi-Conductive Screening

• Conductor Screen
• Insulation Screen

These are non-metallic layers used mainly in XLPE medium- and high-voltage cables to ensure uniform electric stress.

---

Summary Table

Type	Abbreviation	Material	Typical Application
Copper Tape Screen	CTS	Copper Tape	MV/HV Power Cables
Copper Wire Screen	CWS	Copper Wires	MV/HV Power Cables
Copper Wire & Tape Screen	CWTS	Copper Wires + Tape	XLPE Power Cables
Aluminium Foil Screen	AFS	Aluminium Foil	Instrumentation Cables
Copper Braid Screen	CBS	Copper Braid	Control and Data Cables
Individual Pair Screen	IPS	Foil/Braid	Instrumentation Cables
Overall Screen	OS	Foil/Braid/Tape	Multi-core Cables
Semi-Conductive Screen	—	Semi conductive  Compound	MV/HV XLPE Cables

Copper Tape Screening (CTS) 

CTS = Copper Tape Screening

Copper Tape Screening is a layer of copper tape wound helically or longitudinally around the insulated cores of a cable. It acts as a metallic screen (shield).

Functions of Copper Tape Screening

1. Provides a path for earth fault current.
2. Reduces electromagnetic interference (EMI).
3. Improves electric field distribution.
4. Protects communication and control signals from external noise.
5. Enhances cable safety and reliability.

Typical Construction

Conductor
    ↓
Conductor Screen
    ↓
Insulation (XLPE/PVC)
    ↓
Insulation Screen
    ↓
Copper Tape Screening (CTS)
    ↓
Inner Sheath
    ↓
Armour (if required)
    ↓
Outer Sheath

Applications

• Medium Voltage (MV) power cables
• High Voltage (HV) cables
• Instrumentation cables
• Control cables
• Communication cables

Abbreviation:

CTS = Copper Tape Screening
Material: Annealed copper tape
Main Purpose: Shielding and carrying fault current in screened cables.

Copper Wire Screening (CWS)

CWS = Copper Wire Screening

Copper Wire Screening consists of annealed copper wires placed helically around the insulated core of a cable to form a metallic screen (shield).

Functions of Copper Wire Screening

1. Provides a low-resistance path for earth fault current.
2. Reduces electromagnetic interference (EMI).
3. Controls the electric field around the conductor.
4. Improves cable reliability and safety.
5. Protects nearby communication and control circuits from electrical noise.

Typical Construction

Conductor
    ↓
Conductor Screen
    ↓
Insulation (XLPE/PVC)
    ↓
Insulation Screen
    ↓
Copper Wire Screening (CWS)
    ↓
Binder Tape
    ↓
Inner Sheath
    ↓
Armour (if required)
    ↓
Outer Sheath

    Applications

• Medium Voltage (MV) power cables
• High Voltage (HV) cables
• Power distribution cables
• Industrial cables
• Substation cables
• 
  

Abbreviation

Symbol	Meaning
CWS	Copper Wire Screening
Material	Annealed Copper Wires
Main Purpose	Shielding and carrying earth fault current

     Difference between CTS and CWS:

CTS	CWS
Copper Tape Screen	Copper Wire Screen
Uses copper tape	Uses multiple copper wires
Lower fault current capacity	Higher fault current capacity
Common in some MV cables	Common in MV and HV cables requiring                     higher short-circuit ratings

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Aluminium Wire Armouring (AWA)

 Aluminium Wire Armouring (AWA)

Aluminium Wire Armouring (AWA) is a layer of aluminium wires applied over the bedding of a cable to provide mechanical protection. It is primarily used for single-core power cables because aluminium is non-magnetic, preventing excessive eddy current losses that would occur if steel armour were used.

Construction

A typical AWA cable consists of:

1. Conductor (Copper or Aluminium)
2. Insulation (XLPE or PVC)
3. Inner Covering/Bedding
4. Aluminium Wire Armour (AWA)
5. Outer Sheath (PVC, PE, or LSZH)

Applications

• Single-core LV and MV power cables
• Underground cable installations
• Cable trays and ducts
• Industrial plants
• Power distribution systems
• Renewable energy projects

Advantages

• Excellent mechanical protection
• Non-magnetic (ideal for single-core AC cables)
• Lightweight compared to steel armour
• Good corrosion resistance
• Easy to install and handle

Limitations

• Lower tensile strength than steel wire armour
• Not recommended where very high mechanical impact resistance is required

AWA vs SWA

Feature	AWA	SWA
Full Form	Aluminium Wire Armouring	Steel Wire Armouring
Material	Aluminium	Galvanized Steel
Magnetic	No	Yes
Typical Use	Single-core AC cables	Multi-core cables
Weight	Lighter	Heavier
Corrosion Resistance	Better	Good (galvanized)
Mechanical Strength	Moderate	High

Applicable Standards

• IEC 60502-1 – Power cables up to 1 kV
• IEC 60502-2 – Power cables from 6 kV to 30 kV
• BS 5467 – XLPE insulated, PVC sheathed armoured cables
• BS 6724 – LSZH armoured cables

Manufacturing Process

1. Conductor Stranding
2. Insulation Extrusion
3. Core Assembly (if applicable)
4. Bedding Extrusion
5. Aluminium Wire Armouring (AWA)
6. Outer Sheathing
7. Testing and Inspection

Typical Marking

Cu/XLPE/AWA/PVC
or
Al/XLPE/AWA/PE

This indicates:

• Cu/Al – Conductor material
• XLPE – Insulation
• AWA – Aluminium Wire Armour
• PVC/PE – Outer sheath

Key Point: AWA should be used for single-core AC power cables, while SWA (Steel Wire Armouring) is generally used for multi-core power cables because steel armour on single-core AC cables can produce unwanted magnetic heating.

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MS Access Complete A–Z Shortcut Reference

Below is a comprehensive list of Microsoft Access keyboard shortcuts organized by category.

Shortcut	Action
Ctrl + N	Create a new database
Ctrl + O	Open an existing database
Ctrl + S	Save current object
F12	Save As
Ctrl + P	Print
Ctrl + W	Close current window
Alt + F4	Exit Microsoft Access
F1	Help

---

File Operations

Shortcut	Action
Ctrl + F4	Close active object
Ctrl + Tab	Switch between open objects
Ctrl + Shift + Tab	Previous open object
Alt + F	Open File menu
Ctrl + Y	Repeat last action

---

Navigation

Shortcut	Action
F6	Next pane
Shift + F6	Previous pane
Tab	Next field
Shift + Tab	Previous field
Home	Beginning of field
End	End of field
Ctrl + Home	First record
Ctrl + End	Last record
Page Up	Previous screen
Page Down	Next screen
Ctrl + Page Up	Previous record
Ctrl + Page Down	Next record

---

Record Operations

Shortcut	Action
Ctrl + +	New record
Shift + Enter	Save current record
Esc	Undo field change
Esc (twice)	Undo record changes
Ctrl + ;	Insert current date
Ctrl + Shift + :	Insert current time
Ctrl + '	Copy value from previous record

---

Editing

Shortcut	Action
Ctrl + C	Copy
Ctrl + X	Cut
Ctrl + V	Paste
Ctrl + Z	Undo
Ctrl + A	Select all
Delete	Delete selection
Backspace	Delete previous character
Insert	Toggle Insert/Overwrite

---

Find & Replace

Shortcut	Action
Ctrl + F	Find
Ctrl + H	Replace
Shift + F4	Find Next

---

Form View

Shortcut	Action
Alt + Down Arrow	Open combo box
Space	Check/Uncheck checkbox
Enter	Move to next field
Shift + Enter	Previous field
Ctrl + Enter	Insert line break

---

Datasheet View

Shortcut	Action
Tab	Next column
Shift + Tab	Previous column
Enter	Next row
Shift + Enter	Previous row
Ctrl + Space	Select column
Shift + Space	Select row
Ctrl + A	Select all records

---

Design View

Shortcut	Action
F4	Property Sheet
F7	Code Builder
Shift + F2	Zoom Box
Alt + Enter	Properties
Ctrl + G	Immediate Window (VBA)

---

Query Design

Shortcut	Action
Alt + Q	Query Tools
Ctrl + R	Run query
Ctrl + L	SQL View
Alt + Enter	Properties

---

Reports

Shortcut	Action
Ctrl + P	Print report
Ctrl + F2	Print Preview
Esc	Exit Print Preview

---

VBA Editor

Shortcut	Action
Alt + F11	Open VBA Editor
F5	Run procedure
F8	Step Into
Shift + F8	Step Over
Ctrl + Break	Stop execution
Ctrl + G	Immediate Window
Ctrl + R	Project Explorer
F4	Properties Window
Ctrl + Space	IntelliSense
Ctrl + J	List Members

---

Ribbon Shortcuts

Shortcut	Action
Alt	Activate Ribbon
Alt + H	Home tab
Alt + C	Create tab
Alt + X	External Data
Alt + Y	Database Tools
Alt + F	File menu

---

Text Editing

Shortcut	Action
Ctrl + Left Arrow	Previous word
Ctrl + Right Arrow	Next word
Ctrl + Backspace	Delete previous word
Ctrl + Delete	Delete next word
Shift + Arrow Keys	Select text
Ctrl + Shift + Arrow	Select word

---

Function Keys

Key	Action
F1	Help
F2	Edit field
F4	Property Sheet
F5	Go To Record
F6	Next pane
F7	Spelling
F8	Extend Selection
F9	Refresh
F11	Navigation Pane
F12	Save As

---

Useful Alt Shortcuts

Shortcut	Action
Alt + Enter	Properties
Alt + Down Arrow	Open dropdown
Alt + Space	Window menu
Alt + Tab	Switch applications
Alt + Print Screen	Screenshot active window

---

Top 20 Most Useful MS Access Shortcuts

Shortcut	Action
Ctrl + N	New Database
Ctrl + O	Open Database
Ctrl + S	Save
Ctrl + F	Find
Ctrl + H	Replace
Ctrl + C	Copy
Ctrl + V	Paste
Ctrl + X	Cut
Ctrl + Z	Undo
Ctrl + A	Select All
Ctrl + ;	Current Date
Ctrl + Shift + :	Current Time
Ctrl + +	New Record
Ctrl + Home	First Record
Ctrl + End	Last Record
F4	Property Sheet
F7	Spelling
F11	Navigation Pane
Alt + F11	VBA Editor
Alt + F4	Exit Access

This collection covers the most commonly used Microsoft Access shortcuts for database management, forms, queries, reports, VBA, and navigation, making it a practical A–Z reference for beginners and advanced users alike.