Electrical Tape

Electric insulation tape colour

Definition

Grey insulation tape

Although it is not overly used in the UK, grey electrical insulation tape is generally used to signal low voltage/phase C.

Black insulation tape

Electricians will mostly use black tape for the insulation of connections and wires.

Red insulation tape

Primarily used as a low voltage tape in the UK. Its definition is different around the world - in the US, red insulation tape indicates low voltage/phase B.

White insulation tape

Often used for various household tasks that involve white cords and wires for external applications.

Yellow insulation tape

Used for low voltage/phase B in the UK. Internationally, yellow tape signals sheath/110V site wiring’. But in the US, it means high voltage/phase C.

Blue insulation tape

Widely used in the UK and indicates low voltage/phase C. This is also the same for the US. Internationally, blue insulation tape means low voltage or neutral sheath/230V.

Brown insulation tape

Not often used in the UK. But internationally, it is recognised as low voltage/phase A. In the US, it is high voltage/phase A.

Green insulation tape

Indicates ‘earth’ in the UK. In the US, it would indicate ‘earth ground’. A yellow and green striped tape would signify ‘earth’ internationally and ‘isolated ground’ in the US.

PVC electrical insulation tape

PVC tape (polyvinyl chloride) is one of several types of plastic electrical tape and is widely used in many similar scenarios to the standard vinyl electrical tape. However, PVC is generally favoured in scenarios where it’s likely to be exposed to very low temperatures. Both vinyl and PVC are viewed as ‘balanced’ plastic tapes, suitable for a broad range of uses - both have similar high-temperature properties, but PVC copes much better when the temperature drops.

PVC tape is also more robust at dealing with other environmentally challenging factors such as adverse weather conditions, metal corrosion and abrasion. For this reason, it’s often favoured for outdoor wiring applications where ruggedness is likely to be a bonus.

PTFE electrical insulation tape

PTFE tape (polytetrafluoroethylene, a synthetic fluoropolymer) is prized for its extremely robust chemical resistance, due to it being almost universally inert. Often referred to as ‘Teflon tape’, it’s highly insoluble even in harsh solvents at temperatures lower than 300 Celsius, and offers good thermal stability without becoming brittle at very low or high temperatures. It also displays excellent dielectric properties, meaning it conducts practically no electricity when in contact with a current.

Cloth electrical insulation tape

Among the main types of electrical tapes, cloth tape is generally less associated with strong dielectric properties, meaning it’s not the greatest choice for jobs where insulation is the key factor. However, cloth electrical tape is prized for its mechanical properties - it’s a very strong and flexible hybrid that’s excellent for fixes and repairs, and can often be found combined with other material types to help increase its temperature performance and conductive resistance.

Rubber electrical insulation tape

Rubber tape is something of an umbrella term, which covers a fairly wide range of subtypes. Vulcanised rubber tape is often used in cable jacketing and repairs where rugged environments - such construction sites or industrial manufacturing plants - call for a very durable wrap.

Other types of rubber tape are chosen for their market-leading dielectric properties; specialist premium products such as ethylene propylene rubber tape are often found in medium-to-high-voltage applications, while general purpose rubber wraps are also a popular choice for low voltage applications, repairs, padding and moisture seals.

Mastic electrical insulation tape

The word ‘mastic’, in the context of electrical tape, refers to the same adhesive type as is commonly associated with decorating and tiling. Mastic tape is essentially a malleable sticky mass with a rubberised backing that’s great for both repairs (it acts a bit like a roll of putty) and insulation (the rubberised backing gives it fantastic dielectric properties too).

Mastic is very often the first choice when the job calls for a high degree of moisture resistance, either from inclement weather or from humidity, steam and aerosols. It’s also incredibly stretchy and flexible, making it good for padding and bulk-wrapping sharp components or connections that would risk abrasion and puncture of more brittle tape types.

Vinyl electrical insulation tape

Vinyl tape is the most common and universal sort of insulation tape used on general wiring, insulation and repair jobs today. Perhaps the archetypal plastic electrical tape, it’s a good flexible all-rounder for a great many situations where a more specialised product isn’t strictly necessary. Vinyl tape offers a handy balance of usability, ruggedness, insulation and resistance to most standard environmental conditions.

Basic but well-made vinyl tape generally gives solid performance against abrasion, moisture, chemicals, and changeable temperatures. It’s very often found in low-voltage household and workplace electrical applications, where it’s a popular choice for insulation, repairs, sealing, protecting and colour coding on wiring jobs of all kinds.

Polyimide electrical insulation tape

Polyimide tape is mainly preferred in applications where a thin, durable tape with high-temperature stability is required, This makes it a leading choice for many demanding electronics jobs in the automotive, industrial and computing industries, such as wrapping or insulating coils, transformers, capacitors and PCBs

Good dielectric performance means it’s also commonly used as a protective layer for delicate electrical components during soldering and circuit-building. It’s generally flame-resistant and can withstand much higher short-term temperature spikes than many other kinds of electrical tape

Polyester electrical insulation tape

Polyester tape tends to be thin and durable, offering particularly tough resistance to edge-tear, abrasion and puncture. It’s typically chemical, solvent and moisture resistant, as well as fairly flame retardant, and can be supplied with various sorts of adhesive backing including acrylic and thermosetting rubber.

A polyester electrical tape has solid dielectric properties and is a popular option in layer insulation and coil cover applications at higher temperatures (up to 130 Celsius).

Glass Cloth electrical insulation tape

Glass cloth tape is typically manufactured from a polyester film reinforced with glass fibre strands and is used when much higher thermal resistance properties are needed. It’s designed to withstand prolonged exposure to temperatures ranging from 130-200 Celsius, and is also mechanically tough with excellent durability against edge-tear and cut-through.

Frequently found being used as a heat-stable insulation layer, it’s also a reasonable electrical insulator with high tensile strength, Glass cloth tape is widely used in applications such as oven controls and furnace power supply systems, in motor leads and switches, and for wrapping coils.

Cambric electrical insulation tape

Cambric tape usually refers to a cotton fabric electrical tape that’s primed and coated in an insulating varnish. It’s most commonly used as a mechanically tough, abrasion and puncture-resistant base layer in a wide range of repairs and protective applications.

Cambric electrical tape is sometimes applied to wiring and connections adhesive side up, before further layers of more dielectrically resistant tape varieties are added over the top of it. This creates a very robust and durable wrap that’s easy to remove cleanly for future maintenance, making it ideal for applications such as busbar insulation, motor leads and service drop connections.

Silicone rubber electrical insulation tape

Silicon rubber tape boasts a particularly wide range of operating temperatures, typically from -80 to around 200 Celsius at peak. It’s also prized for its outstanding dielectric properties and chemical inertness, making it a reliable choice in applications where it might experience prolonged exposure to moisture, UV, ozone, harsh weather or radiation.

In addition, silicone rubber tape is extremely soft and pliable, making it convenient for wrapping around awkward shapes and in tight spaces. However, it’s quite vulnerable to abrasion and puncture and does not offer a high degree of mechanical strength.

Self-amalgamating electrical tape

Self-amalgamating electrical tape does not typically feature any adhesive or solvent ingredients - instead, insulating tapes of this kind fuse to themselves when stretched and wrapped tightly around a wire or connection. The resulting bond is effectively seamless, and can offer an added layer of protection against moisture ingress and current transfer

The lack of adhesive makes self-amalgamating tape easy to remove for repair and maintenance, and it’s often used for short-term repairs against leaks and punctures. In electrical applications, it’s commonly used to moisture-seal joints for insulation purposes, or for splicing and connections in high-voltage cable runs.