Standard Colour Code for Electrical Power Cable and Wiring

Basic Color Code for Power Cable

Basic Colour Code for Electrical Cable and Power Cable 

International standard IEC 60446 developed basic and safety principles for the man-machine interface by marking and identification of electrical cabling and wiring systems. 

Why Need Power Cable Test After Installation

Power Cable Test After Installation

HV/EHV power cable testing in the field after installation is a common requirement for cable users. Meanwhile, MV-normal voltage, HV-high voltage, and EHV-extra high voltage power cables are carefully tested by the manufacturer before consignment with AC-alternating or DC-direct voltage. 

Conductor Stranding Perspective of Power Cable Construction

Conductor Stranding Perspective of Power Cable Construction

Conductor stranding is a major aspect of cable construction that came long experience in different circumstances. 

The problem with larger sizes of solid conductors is too rigid for installation in curvy areas, jointing, and termination work. The solution to these difficulties comes from conductor stranding. 

The procedure of stranding is used depending on the metal temper and types. In general Copper conductor and Aluminum, copper conductors and aluminum conductors are used for power cable construction. Normally Aluminum is softer than Copper, so the use limit is higher than that of copper.

Fig: Conductor strands arrangement system

High Voltage Test for Power Cable

High Voltage Test Guide for Power Cables

A complete high-voltage test guide for power cables is essential for both cable users and contractors to get a clear idea about cable pre-commissioning and commissioning. 

Electrical Power Cable Is an Electrical Transformer

An Electrical Power Cable Is an Electrical Transformer

How does an electrical power cable work as an electrical power transformer? It may be your question. It’s true that we know electrical power cable works as a capacitor, because the condition to be a capacitor, two metallic components need to be placed in parallel. 

Underground Power Cable Site Test after Installation

Fig- Cable High Voltage Testing Kit

Site Test or Pre-commissioning Test, Just after the Underground Power Cable Installation

Many cable failures are the result of poor installation practices; so, all new installations should be thoroughly tested before they are put into service. Since the cable itself will have been tested at the factory, on-site testing of newly installed cables focuses on identifying localized problems that have occurred during installation. 

Site test after installation of the underground power cable is required to confirm that the line is installed correctly and there is no damage during laying.

Amazing High Voltage Power Line and Health Risk

⚡ Are High Voltage Power Lines a Risk to Human Health?

Background: The Debate Over EMF Exposure

Concerns about electromagnetic fields (EMFs) and their impact on human health first gained attention in 1979. Since then, scientific debate has continued without a clear consensus.

• 👨‍🔬 One group argues that prolonged exposure to residential power lines may increase the risk of cancer in children and young adults.

• 🧪 Another insists that ambient EMF levels are too weak to pose serious health threats.

Despite extensive studies, definitive evidence remains elusive. Nonetheless, numerous articles suggest that high-voltage transmission lines may contribute to health issues ranging from headaches and skin disorders to cancer.

How Does Superconductor Work?

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What is a superconductor? 

We want to know how superconductors work and what a superconductor material is. The material that achieves the superconductivity property is known as a superconductor. Now, the question is, what is the superconductivity property? How can a material achieve the superconductivity property?

This phenomenon was first discovered in 1911 by Heike Kamerlingh Onnes, and it has since led to various technological advancements and applications.

Commissioning and Test Procedure of Power Cable and Equipment

Testing methods for power cable insulation depend basically on the type and material of cable insulation. Cross-linked Polyethylene (XLPE) is now spreading widely for power cable insulation at the rated voltage of 66 to 500 kV worldwide.

Quick and easy understanding of commissioning tests for transmission lines and major equipment. Here specially focused on the underground power transmission line, underground cable megger testing, cable fault location and main causes of cable fault, and some manufacturing faults. You also find some megger test procedures for transformer or circuit breakers, or common methods for insulation tests and megger tests.   

To see the slide view, click the link below,

Electrical Power Cable Short Circuit Current Capacity

How Calculate Cable Short Circuit Current from Short Circuit Current from Table?

You may find the short circuit current for a particular type of cable for a specified period of time from your cable manufacturer’s provided catalogue. For example the below table is showing different sizes from 16 square mili-meter to 2500 square mili-meter of cable in first left column and time duration from 0.1 second to 5 second in next 10 columns.

Cable Basic Parameters Resistance, Inductance and Capacitance

Cable Basic Parameters Resistance, Inductance, and Capacitance

What Happen If Cables Placed In Magnetic Metal Conduit

What Happens If Cables are Placed In Magnetic Metal Conduits 

Do we know what happens if cables are in a magnetic metal conduit? Yes, at least we know that in any circumstances, the individual phase of an AC (alternating current) circuit is in a separate magnetic metal conduit. 

Manufacture Of Electric Power Cables and Chronological Development

Underground Power Cable Installation

This Video Clip shows how to install underground power cables. 

This is not used in modern equipment and technology.

You could see the initial technology for the oilfield underground power cable and its installation and erection procedure. 

Why is Powder Used inside Cables?

Fig-Different Types of Cables

The Reason Why Various Powder Used Inside Electrical Cables

You may notice some white powders are used in electrical current-carrying power cables. Obviously, some questions arise in your mind about why they are used.

 So let's discuss why is white powder used inside electrical power cables. Hope this article will give questions' answer.

Various powders are used inside power cables for various reasons according to the requirement.

Partial Discharge in HV & EHV Power Lines

A video clip for Brug cable PD Measure

Partial Discharge in High and Extra High Voltage Lines

Partial Discharge (PD) is very important for Underground Power Cables. If you work with Power Cable, you must know why and where Partial Discharge is present. It will help to take action at the right place at the right time. 

ARMOUR EARTHING ASSEMBLING FOR SINGLE CORE CABLE

Armour Earthing Assembly for Wire Armour Single Core Cable

33kV Cable Earthing System

Cable armour earthing is important for medium voltage (MV), high voltage (HV) and extra high voltage (EHV) system. 

Our discussion on this article is limited only single core plastic or paper cable wired armour earthing procedure for medium voltage (MV) system or 7.2 kV to 36 kV ranges.

The crystal clear step-by-step assembly figure shown the complete procedure of earthing system for wired armour cable.

If you follow the shown 9 step carefully, we hope you will be able to assemble the cable armour earthing successfully.

9 Step to Earth Cable Armour  

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1. First of all remove the over-sheath according to the dimension given the appropriate manufacturer Installation Instruction, Remove the armour according to dimension as per shown in the drawing. Clean the end of the over-sheath for a length of 250 mm.
2. Then slide the outer sleeve over the cable, and disassemble the clamping rings. Slide one clamping ring lug-downwards over the cable as shown in the figure 2.
3. Following the figure no-3 spread the armour wires as shown in the drawing and screw the other clamping ring loosely to the lugged clamping ring.
4. Install the termination in accordance with the Installation Instruction of termination manufacturer. Pass the end of the earth lead down through the clamping rings and connect it to one lug of the clamping ring. Tighten the clamping rings, refer to figure no-4.
5. With a small overlap and slight tension wrap two layers of sealant tape round the overs-heath for a length of 50 mm, just below the armour wire ends. Wrap two layers of sealant tape round the earth conductor so that it will be just below the armour wire ends. Attach the earth conductor to the other lug of the clamping ring as figure-5.
6. As shown in figure-6, bend the armour wires back and bind the ends to the over-sheath with a wire binder or plastic tape. noted that all sharp wire ends must be covered with plastic tape.
7. With a slight tension and small overlap wrap two layers of sealant tape over the lower end of the termination for a length of 50 mm.
8. Position the top end of the outer sleeve level with the top of the sealant tape. Shrink it into place starting at the center. Shrink the lower end first and work towards the upper end.
9. Yes, you have done; installation of earthing assembly for armour is completed.

This is the basic instruction for cable armour earthing, to do it physically you must follow the manufacturer installation instruction and necessary safety code. If it is helpful, then share with others to help them. 

Thermosetting and Thermoplastic: Cable Insulation

Thermosetting and Thermoplastic:  Cable Insulation

PVC-insulated cables are not going to be called pvc cables anymore they are thermoplastic insulated cables and rubber cables are thermosetting! The use of the terms thermoplastic and thermosetting is the solution to the problem of an ever increasing number and variety of materials and blends available for the manufacture of cables. 

POWER CABLE TERMINATION AND SEALING

Power Cables Termination and Sealing End Requirements

The servicer should terminate and connect up the power cables in accordance with diagrams or details approved by the employer Engineer. 

Considering the following requirements, power cable along with others controlling and communication cable sealing end should be terminate in an adequate manner.

Underground Power Cable Termination Coupling With Over Head Line

PARTIAL DISCHARGE TESTING OF POWER CABLE

Partial Discharge (PD) in Electrical Power Cable:

Why PD?

No matter way where you are an engineer or a technician for electrical power cable, you need a piece of pretty good knowledge about Partial Discharge or shortly PD to understand your cable life or the possibility of unwanted cable faults. You may gather knowledge about PD by watching video clips on YouTube or reading a blog or article about PD.

Introduction of Partial Discharge (PD):  

Partial discharge (PD) is one of the most important factors for a power cable system. The partial discharge measurement methods of assessing the quality of the insulation of power cable systems, especially for extruded insulation materials.

Where Partial Discharge Occur:

We can think of partial discharge for cable systems from two major points of view:

01. Partial Discharge within the whole cable

02. Partial Discharge in an individual              location

Partial Discharge Measurement:

 

Normally major factory test carried out on the insulation of the whole drum of extruded cable is the partial discharge test. This is usually done at power frequency, but can also be carried out at very low frequency and at some voltage significantly higher than normal working voltage to ground. PD test is a very sensitive method to find out very minor failures such as little void or skip of insulation layer during manufacturing time.

But this factory test is not sufficient for the end users of the cable systems, during cable shipping, cable installation, cable jointing, and termination; cable insulation may damage or crack. Minor damage or crack is not possible to find out during commissioning or energizing time. After a little longer time this defect increased slowly and finally cracked. By statistics from the cable systems, most of the cable faults occur in cable jointing and termination point.

For Better Results:

So it is better to observe the magnitude and phase of the partial discharge signals and how they vary with increasing and then decreasing test voltage, results will disclose information on the type and position of the defects and their probable effect on cable life.

Finally in conclusion we can say, if the cable system can be tested in the field to show that its partial discharge level is comparable with that obtained in the factory tests on the cable and accessories, it is the most convincing evidence that the cable system is in excellent condition.

Recycling of Underground Power Transmission Line

What happened to Underground Power Cable Line after it finished Lifetime:

What will happen to the underground power transmission line at end of service life, the cable can be recovered for recycling or left in place forever.

In a conventional overhead power transmission line, every part of the material including the conductor is easy to recollect and recycle.

Direct buried cable is not so easy to recollect from 1.5-meter deep earth. Still, lots of oil-filled cables which already buried, and we can’t just leave them in place after the end of their service life, they are containing some hazardous materials, leaking oil to the vicinity for a long time!

The good news is that modern special graded XLPE cables replace older oil-filled cable technology, polyethylene which has cross-linked molecules to allow extremely high temperatures without melting.

Typically each circuit line has 3 conductors and the amount of copper up to 25 tons per kilometer for a larger core. This hues amount of copper can recycle into the same graded copper which can recover plant costs and keep a positive footprint for carbon-di-oxide emissions.

During planning and designing a new underground power transmission line project, it should consider the recycling of cables. Route line selection and laying procedure should be well-matched to cable recycling in the future.