Instrument Cable: All You Need To Know Before Custom One

Regardless of which process industry you work in, high-quality cables are a must. Instrument cables are versatile because they come in handy for numerous applications like transmitting data and signals and power transmission.

As a manufacturer, we provide custom solutions for all your wiring and cable needs. However, merely offering products is not enough; we need customers to be informed and aware of making the best purchase decision.

After all, how do you purchase the best cables for your setup? To do that, you need to start from the basics: what makes up an instrument cable?

The different types and what to look for in an instrument cable manufacturer. To make it easy for you, we will get into the complexities of instrument cables and answer any questions you might have.

Chapter 1: What Is An Instrument Cable

This cable comprises multiple conductors that help transmit signals with a low-energy signature.

They are suitable for power control, monitoring electrical systems, and other similar processes. Apart from power transmission, they also help carry out essential functions that allow smooth operations in process industries.

They are helpful with communication and control settings, like process industries that involve various systems.

The Basics On An Instrument Cable

Most versions of instrument cables work at voltage levels between 24V and 110v. They must remain insulated from external electrical components that can cause interference.

You also must not install an instrument cable in the same tray as the power line. Even if you do, keep a distance of at least 30 cm.

Insulation And Jacket Types

Mainly, manufacturers offer three different insulation types and jackets, allowing customers to choose between them for customization.

Fiber

Fiber-based jackets are common in higher temperatures because they offer ideal heat resistance. Fiber-based jackets are also flame resistant, so you can apply them over braids for rubber insulation.

Thermoset

This type is a group of compounds set or hardened by a cross-linking application through irradiation or vulcanization, which involves adding heat and pressure. The different kinds of thermoset plastics include silicone rubber, EPR, XLPE, and CPE.

Thermoplastic

Thermoplastics are the first layer of insulation used on the wire and cable. The material softens when heated but is firm when cooled.

There are different thermoplastics, such as TPE, Fluoropolymers, and PVC. Each of these comes with a unique set of features.

Chapter 2: What Instrument Cable Factors Affect Quality?

When choosing an instrument cable, these are a few of the key things you should look for:

Screening

It would help if you screened your instrument cable to minimize noise. Screening shields the conductor from electrical interference. Usually, manufacturers apply a conductive plastic jacket of braided copper.

Capacitance                     

A cable’s capacitance is how it can respond to differences in voltage. Measured in pF per foot or meter, a figure of around 70 pF/m is low for an instrument cable.

Low capacitance for equipment with high impedance means a stable frequency response.

Besides, you can measure the capacitance of a cable per unit of length. A longer cable will provide more capacitance as opposed to a shorter one. Hence, it is best that you only use as much as you need.

Connectors

You do not need to opt for an expensive connector. Any mono jack plug that provides adequate performance will work fine, even if you get gold-plated connectors.

You will likely plug it into an ordinary nickel-plated amplifier jack, which cancels out any benefit you would get from gold plating in the first place.

The reason why gold-plated connectors are preferable in some situations is not because of their conductivity but rather their corrosion resistance.

The disadvantage of gold plating is that it is soft, so it is not suitable for excessive wear and tear applications.

Chapter 3: What Instrumentation Cable Manufacturers Should Tell You

Wondering how you should choose the best instrument cable manufacturer? We will walk you through the different factors that you should look for in their products. Besides, we will also cover other services they should offer a better customer experience.

Product Quality

• For starters, aluminum or stranded copper is the principal conductor in instrument cables. Although copper is more cumbersome and denser than aluminum, it offers more conductivity. In contrast, aluminum conductors for instrument cables with equal conductivity tend to give a 1.6-time larger cross-sectional area than copper wire but are half the weight.

Using Conductors in Instrument Cables

• You can coat a copper conductor can on the surface of a wire (typically made from lead, silver, nickel, or tin alloy). This is common to keep the insulation from adhering to the copper. This also helps prevent the copper from deteriorating at higher temperatures.
• Previously, a tin coating protected the conductor from corrosion due to rubber insulation that contains sulfur traces for vulcanization.
• On the other hand, the conductor can undergo annealing, which slowly heats and cools it to make it less brittle and more malleable.
• The most commonly used materials are thermosetting or thermoplastic.
• In most cases, every bunch of insulated conductors features a separate screen to shield it from interference caused by other conductors. Manufacturers usually use metallic or semi-metallic braid or tape screens.
• A drain wire is associated with each screen to help screen termination.
• Apply a final shield to all insulated conductor bundles to shield radiation, noise, and electrical interference from surrounding cables. 
• Manufacturers often use metallic or semi-metallic braid or tape screens.
• Manufacturers use a steel wire braid or armor to protect the conductor bundle mechanically. They also galvanize it to prevent rusting, while tinned copper or bronze phosphorus is a suitable substitute for steel armor.

• The outer sheath goes over the armor to act as overall mechanical protection. This is usually a thermosetting or thermoplastic compound, often the same material as the bedding.

The outer sheath features color-coding so that users can differentiate between instrumentation, HV, and LV cables. Other markings, such as length, are on the outer sheath.

They Should Also Offer

• Your cable manufacturer should have a strategic position that allows them to provide better lead time and quick delivery.
• Compliance with environmental policies is crucial.
• Product standardization, so it’s easy for customers to compare different manufacturers and their products.
• A reliable manufacturer should have advanced technology to develop durable and robust instrument cables.
• Seamless customer service by responding to queries and requests for more information
• Information about their quality assurance certificate to avoid compliance issues later.
• You get added value from hiring high-quality pre-sales and post-sales service.

As a reliable instrument cable manufacturer, CLOOM Tech can attest to meeting all your cable needs at an affordable price. We can customize your order based on special application requirements so you get the best performance possible.

Chapter 4: Instrument Cable Vs. Speaker Cable

There’s a general assumption that instrument and speaker cables may even be interchangeable since they look similar. However, this isn’t the case – and you need to know the differences between them to understand why you shouldn’t make such a mistake.

How Instrument Cables Work

Instrument cables have high impedance and low power because of the manufacturing process. This is so that it can transmit a weak signal from one piece of equipment to another, such as from a guitar to an amplifier, from where it gets a boost to a more usable level.

Since it only needs to carry a minimal DC with a small voltage, it only comprises a single positive inner wire with a small diameter.

It’s often a 24-gauge wire running through an outer jacket, many insulators, and braided shielding that acts as the ground connection.

Instrument cables have a lightweight wire with a small size that offers excellent flexibility, while the shielding prevents much noisy electromagnetic interference that affects low-power signals.

How Speaker Cables Work

However, what about your speaker cable? It’s the opposite of an instrument cable – it has low impedance and high power.

The cable can carry a stronger signal from your amplifier to the speakers. The signal comprises a higher voltage and AC, while your instrument cable has one wire.

Your speaker cable has two, each with a much larger diameter, to permit better signal transmission from amplifiers to speakers.

Using An Instrument Cable Instead Of a Speaker Cable

You might not find any adverse effects at low signal levels using an instrument cable instead of a speaker cable.

However, you’ll start seeing major problems at higher signal levels because a large amount of amplifier power will need to flow through the cable’s conductor, which is too small.

As a result, much of that amplifier power doesn’t reach the speakers and converts to heat instead. In terms of speakers, you get less output and maybe even some distortion, but in extreme cases, you’ll experience cable connector or heat-induced cable failure.

No one wants their amplifier to overheat, so you’d best avoid making this mistake.

Using A Speaker Cable As An Instrument Cable

Also, what about vice versa: if you use a speaker cable instead of an instrument cable? In this case, the large conductors in speaker cables can handle a weak signal.

However, there is no shielding. Because of their purpose to carry amplified and high-level signals, any noise they pick up as electromagnetic interference is minimal, eliminating the need for shielding.

If you use speaker cables as an instrument cable, external AC sources like amplifier power supplies and fluorescent lighting will cause interference that affects signals.

If you want a more visual representation of the differences between the two types of cables, you should check out this informative video.

Chapter 5: Instrument Cable FAQ

Have some questions about instrument cables? As manufacturers that provide a custom cable service. We’ve come across countless customers who want to get as much information about different types of wires as before they get around to using them.

That’s why we compiled some of the most commonly asked questions so you can make an informed purchase.

1.      Can I Use A Speaker Cable Instead Of an Instrument Cable?

Speaker cables and instrument cables are different because they fulfill a unique purpose. If you try to use one instead of the other, you’ll experience adverse effects from interference to equipment failure.

So, no, you can’t use a speaker cable instead of an instrument cable. If you require a control cable for any production process or industrial setting, it’s best to rely on a trusted cable manufacturer to address your needs.

2.      Do You Provide Custom Cable Services?

As a leading manufacturer in the industry, we create custom cables for clients based on specific shielding, conductors, and insulation requirements. This ranges from material selection to other aesthetic features as well.

3.      What Is Cable Shielding?

Instrument and control cables can come with electromagnetic shielding wrapped around the cable underneath the plastic jacket.

Shielding keeps electrical noise from impacting transmitted signals while reducing electromagnetic radiation emitted from the wire.

Usually, shielding includes foil braiding, metal tape, or a type of metal braiding. While assembling a shielded cable, manufacturers may also use a special grounding wire called a drain wire.

4.      Why Do Instrument Cables Need Screens?

As explained before, instrument cables need screening because industrial environments hold many processes, machines, and welders that can create excess electrical interference.

Also called noise, it can distort clarity when signals transfer from one piece of equipment to the next. This can result in false readings that impact overall results.

5.      How Can I Find Out a Cable’s Rating?

A cable’s ability to dissipate heat generated due to the current passing through the conductor determines the continuous current rating.

Ultimately, the cable’s grade depends on various factors, but some of the most important include the following:

• Conditions of the surrounding environment, such as the air temperature
• Insulating sheathing materials’ thermal resistance
• Conductors’ DC resistance

6.      What’s The Difference Between Insulation and Jackets?

Insulation is a layer taped or extruded onto the bare conductor wire to separate them from each other, both physically and electrically. Different types of insulation vary based on the application.

In contrast, the jacket is an outer sheath that shields the cable core, or wire, from chemical issues, moisture, and mechanical interference.

Jackets assist with installation, protect the conductor from sunlight, and assist with flame resistance. They come in some styles and types and are mainly rubber or plastic-based.

7.      Does A Fire Rating Mean The Instrument Cable Won’t Catch Fire?

Cables witFirefire rating keep functioning during a fire for a certain amount of time so that people can safely evacuate the building.

The fire rating cable maintains emergency lighting and smoke handling systems. However, this doesn’t imply that the wire won’t burn.

It will, but in a way that ensures the circuit functions for a certain time during the fire.

8.      CaFireu Use a Fire Rating Instrument Cable in Constantly Hot Environments For Long Periods? 

A fire rating doesn’t qualify an instrument cable for prolonged use in high temperatures. If you need to use the cable in such environments, you must design it using unusual materials like glass fiber or silicone.

9.      What’s The Difference between Armored and Unarmored Cables?

Aside from the apparent lack of metal armor, an armored cable also has an inner sheath.

Conclusion

We understand how essential any process industry’s basics are for higher productivity levels. Whether it’s circuit boards, wire harnesses, or instrument cables, they all play a critical role in maintaining efficiency in our daily lives.

We gave you a comprehensive introduction to instrument cables with this blog by discussing some basics. However, this is just the beginning, so if you want to learn more about our services, company, or processes. You can always contact us – we’d love to hear from you!