Custom Ethernet Cable Assemblies | Cat5e, Cat6 & Cat6A
Published on 9/16/2026 • Updated on 9/16/2026
SigmaRF is a custom cable assembly manufacturer, known for RF and coaxial assemblies and now manufacturing Ethernet cable assemblies for OEMs, network equipment companies, system integrators, data centres and industrial customers. Send us a drawing, a specification or an existing cable, and our engineering team will review it and quote.
When a standard patch cord won't do
Off-the-shelf patch cords come in fixed lengths like 1 m, 2 m and 3 m, with limited choices for shielding, jacket and colour. That leaves excess slack in racks, cables that don't match your equipment drawings, and no control over what arrives in the next batch.
We build to the length you actually need, such as 0.35 m, 1.25 m or 3.7 m, and keep the construction identical from one production batch to the next.
Choose your cable category
| Category | Bandwidth | Ethernet support | Typical applications |
|---|---|---|---|
| Cat5e | 100 MHz | 1000BASE-T (1 Gb/s) up to 100 m | Switches, computers, servers, IP cameras, wireless access points, VoIP phones, industrial Ethernet, general network infrastructure |
| Cat6 | 250 MHz | 1000BASE-T up to 100 m; 10GBASE-T over shorter distances, depending on installation | Enterprise networks, network cabinets, servers, PoE equipment, industrial networking, wireless access points |
| Cat6A | 500 MHz | 10GBASE-T (10 Gb/s) over the full 100 m channel in a properly designed system | Data centres, 10 Gigabit networks, high-performance servers, network switches, Wi-Fi infrastructure, industrial automation, high-density environments |
Network performance depends on the complete cabling channel, including installed cable, patch panels and cords, not on the patch cable alone. Other categories can be considered after engineering review.
Everything you can specify
| Specification | Options |
|---|---|
| Cable category | Cat5e, Cat6, Cat6A |
| Shielding | U/UTP (unshielded), F/UTP, S/FTP and other shielded constructions |
| Cable profile | Standard round, slim, ultra-slim, and flat where appropriate |
| Conductor | Solid or stranded, to suit the application |
| Conductor gauge | Selected to suit the application |
| Length | Any length you specify |
| Connector | RJ45 / 8P8C, shielded or unshielded; other network connectors on request |
| Wiring | T568A, T568B or your specified pinout |
| Boot | Standard, snagless, colour options or custom boots |
| Jacket | PVC, LSZH, PE or other application-specific materials |
| Colour | Black, blue, grey, red, yellow, green, orange; other colours subject to material availability |
| Marking | Cable ID, part number, sequential numbering, customer identification, custom labels |
| Packaging | Individual, bulk or OEM packaging |
Which shielding do you need?
| Construction | How it's built | Where it fits |
|---|---|---|
| U/UTP | No overall shield, no shield on individual pairs | Offices, general networking, low-noise environments |
| F/UTP | Overall foil shield around unshielded pairs | Areas with moderate electrical noise, such as near power cabling or machinery |
| S/FTP | Overall braid shield plus a foil shield on each pair | High-noise industrial sites, dense data-centre cabling and demanding Cat6A links |
Shielded cable performs as intended only when paired with shielded connectors and a properly grounded system. If you are unsure, tell us about your environment and we will recommend a construction.
Built for OEM and production programmes
Many of our customers need the same assembly, built the same way, every time. We work with you from first sample to recurring orders.
| If you need | Send us | What we do |
|---|---|---|
| Build-to-print assemblies | Engineering drawing, BOM or cable specification | Manufacture exactly to your documentation |
| A copy of an existing cable | The cable itself or its current specification | Evaluate and reproduce it, subject to engineering review |
| Supply against your part numbers | Your internal part number and specification | Build and supply under your part number |
| Production at any stage | Your volumes for prototype, pilot or recurring runs | Keep the specification consistent across batches |
| Cable identification | Your ID, label or numbering scheme | Apply labels, part numbers or sequential marking where supported |
Industries we serve
| Industry | Typical applications |
|---|---|
| Networking and IT infrastructure | Switches, routers, servers, network racks, patch panels, network appliances |
| Data centres | Server racks, switch-to-server links, storage systems, rack interconnects; exact lengths reduce slack and keep racks organised |
| Industrial automation | Links between controllers, HMIs, sensors and network equipment, with extra shielding, mechanical protection or special jackets where needed |
| Telecom and communications | Telecom and network equipment, communication systems, test equipment, field installations |
| CCTV and security | IP cameras, NVR systems, PoE switches, access control, security infrastructure |
| OEM equipment manufacturers | Networking appliances, industrial equipment, control systems, electronic and communication equipment |
| Medical and electronic equipment | Interconnects where length, cable geometry, jacket material or identification must follow the equipment maker's specification |
Cables for Power over Ethernet (PoE)
Ethernet cables can also carry power to PoE cameras, wireless access points, VoIP phones, IoT and industrial network devices, sensors and access-control equipment. Not every cable suits every PoE application, so we review your requirement before recommending a construction.
| What we consider | Why it matters |
|---|---|
| Conductor size | Thinner conductors have higher resistance, so they lose more power and run warmer |
| Power level | Higher-power PoE devices draw more current through the cable |
| Bundling | Cables packed in large bundles trap heat, which reduces how much current they can safely carry |
| Operating temperature | Hot environments leave less headroom for heat generated by PoE |
| Connector compatibility | Connector contacts must suit the cable and the power being delivered |
Our background in RF cable assemblies means we look at the electrical performance of the whole assembly, not just whether it connects.
Testing and quality
Every assembly is built to the approved specification and tested to the test plan agreed at the time of order. Depending on the cable and application, testing can include:
| Test | What it checks |
|---|---|
| Continuity | Every conductor is connected end to end |
| Wire map | Each pin connects to the correct pin at the other end, as per the specified wiring scheme |
| Short and open detection | No conductors are shorted together and none are broken |
| Pin configuration | The pinout matches your drawing or specification |
| Termination inspection | Connectors are correctly crimped and the strain relief is secure |
| Electrical testing | Electrical parameters called out in your specification |
| Transmission performance | Category performance parameters, where specified and applicable |
We state exactly which tests were performed on each order. Continuity and wire-map testing confirm correct assembly; they are not the same as category performance certification, which is carried out only where it is specified.
What to include in your quote request
The more of this you can share, the faster and more accurately we can quote. If you don't know an answer yet, tell us how the cable will be used and we will help you choose.
| Detail | Example |
|---|---|
| Cable category and shielding | Cat6A, S/FTP |
| Length | 1.25 m, with any length tolerance you require |
| Quantity | Prototype quantity and expected annual volume |
| Connectors | Shielded RJ45 both ends |
| Wiring | T568B straight-through |
| Jacket and colour | LSZH, grey |
| Boot | Snagless, grey |
| Marking and packaging | Your part number on a label, individually bagged |
| Application | PoE access points, industrial panel, data-centre rack, etc. |
| Supporting documents | Drawing, specification, BOM or a sample cable |
Frequently asked questions
Can you manufacture Ethernet cables to a custom length?
Yes. We build Ethernet cable assemblies to the length you specify, from short equipment interconnects to longer runs, subject to the selected cable and application.
Do you make custom Cat6 cables?
Yes. Cat6 assemblies can be configured for length, cable construction, jacket, colour, connectors, boots and marking.
Do you make Cat6A cable assemblies?
Yes. We supply custom Cat6A assemblies for 10 Gigabit and other higher-performance twisted-pair applications.
What is the difference between Cat6 and Cat6A?
Cat6 is specified to 250 MHz and Cat6A to 500 MHz. Cat6A is designed to run 10GBASE-T over the full 100 m channel when the complete cabling system is properly designed; Cat6 supports 10GBASE-T only over shorter distances.
Can you make shielded RJ45 cables?
Yes. Shielded assemblies are built with shielded cable (such as F/UTP or S/FTP) and compatible shielded RJ45 connectors.
Can you make LSZH Ethernet cables?
Yes, where the selected cable construction is available with an LSZH (low smoke zero halogen) jacket.
Can I choose the cable colour?
Yes. Jacket and boot colours can be specified, subject to the chosen construction and material availability.
Can you make very short Ethernet cables?
Yes. Short assemblies for racks, cabinets and equipment interconnects are a common request, subject to manufacturing requirements.
Do you make T568A and T568B cables?
Yes. Assemblies are wired to the scheme you specify. Please state the required pinout when you request a quote.
Can you build Ethernet cables for OEM equipment?
Yes. We manufacture against your drawings, specifications, internal part numbers or approved samples.
Can I send an existing cable as a sample?
Yes. Send us the cable and we will review its specification for reproduction, subject to engineering evaluation.
Can you add labels or part numbers to the cables?
Yes. Customer-specific identification, part numbers and sequential marking can be arranged for OEM and production orders.
Are your cables suitable for Power over Ethernet (PoE)?
It depends on the device's power level, conductor size, bundling and operating temperature. Tell us your PoE application and we will recommend a suitable construction.
Need an Ethernet cable that isn't on the shelf?
Send us your drawing, specification or sample cable. Our engineering team will review it and come back with a quotation.
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