Skill: Cable Types — Understand Cat5, SWA, Flex, Direct Burial & More
Skill level: 2
Wiring
Learning Objective
Gain a clear understanding of the most common cable types used in gate installations, CCTV, intercoms, and power supply — including where and how each type should be used for safety, compliance, and longevity.
1. Overview
Understanding cable types and their specific uses is essential for safe, reliable, and professional installations. Each cable has unique electrical, mechanical, and environmental properties that determine where and how it should be used. Using the correct type ensures optimal signal quality, adequate power delivery, and long-term durability while maintaining compliance with safety standards. Choosing the wrong cable can lead to faults, interference, corrosion, voltage drop, or even electric shock hazards. A good understanding of cable selection also improves efficiency, reduces maintenance costs, and demonstrates competence and professionalism in every gate, intercom, or CCTV installation.
2. Common Cable Types
There are many different types of cable used in electrical, data, and control installations. Each has specific properties that make it suitable for certain tasks and unsuitable for others. Below is a breakdown of the most common cable types used in gate automation, intercom, CCTV, and control systems, with their typical uses and key characteristics explained.
Cat5e / Cat6 (Twisted Pair Data Cable for IP Networks)
These cables are designed for data transmission over IP networks, using twisted pairs to reduce interference and maintain signal quality.
Cat6 is the newer standard, offering faster data speeds and better shielding than Cat5e, making it more reliable for high-speed or interference-prone environments.
Typical uses include:
IP intercoms
IP CCTV cameras
GSM intercom systems
Network routers and switches
Shotgun Cable (Coaxial with Twin-Core Power)
Shotgun cable combines a coaxial video cable with a twin-core power cable, running side by side in one sheath.
It was commonly used for analogue CCTV systems where the video and power needed to run together from a DVR to a camera.
Typical uses include:
Analogue or Turbo HD CCTV systems
Legacy installations where IP cameras have not been fitted
Flexible (Flex) Cable (Multi-Core, Thin-Sheath Flexible Cable)
This is a light, flexible multi-core cable with a soft outer sheath, making it easy to route inside equipment enclosures or gate posts.
It is not designed for long runs or outdoor exposure, but is ideal for short low-voltage connections inside protected areas.
Typical uses include:
Wiring within control boxes
Connections between internal components
Small, enclosed low-voltage circuits
SWA (Steel Wired Armoured Cable)
SWA cable is a tough, durable power cable that includes a steel wire armour layer for mechanical protection.
It is designed for 230V mains supplies, especially where cables are run underground or exposed to physical damage risks.
Typical uses include:
Power supplies to gate control boxes
External runs clipped to walls or fences
Underground mains feeds to remote equipment
3-Core Flex (Standard Mains Flex – Brown/Blue/Green-Yellow)
This is the standard flexible mains cable used for domestic and light industrial applications.
It contains live (brown), neutral (blue), and earth (green/yellow) conductors and is suitable for short runs of 230V.
Typical uses include:
Connecting control boxes to fused spurs
Lighting connections
Low-power accessories such as pumps or chargers
Direct Burial (DB) Cable (UV Stable, Waterproof)
Direct Burial cable is designed to withstand long-term underground use without conduit.
It features a UV-stable, waterproof outer jacket, making it ideal for outdoor or damp conditions.
Typical uses include:
Alarm or Cat5 cable in underground ducts or trenches
Power cables for long external runs where conduit isn’t practical
Duct Grade Cable (Heavy-Duty, Moisture and UV Resistant)
Duct grade cable is reinforced for use in underground ducts and can also be buried directly.
It is tougher and more moisture-resistant than standard data or alarm cables, reducing the risk of degradation over time.
Typical uses include:
Cat5e/Cat6 network runs through underground ducting
Power and control cables where additional durability is required
Alarm Cable (6 or 8 Core Thin Multi-Core Signal Cable)
Alarm cable consists of multiple small signal cores, typically 6 or 8, within a thin PVC sheath.
It is designed for low-current signal and control applications, and should only be used in short, protected runs.
Typical uses include:
Push buttons and key switches
Photo beam sensors
Keypads and low-voltage control lines
Co-Ax (RG59 – Legacy CCTV Video Cable)
Coaxial cable, particularly RG59, was the traditional video transmission cable used in older CCTV systems.
It carries analogue video signals but is now largely replaced by Cat5e/Cat6 cabling used in IP-based camera systems.
Typical uses include:
Legacy analogue CCTV installations
Systems that have not yet been upgraded to IP
Speaker Cable (Parallel Red/Black Cores)
Speaker cable consists of two parallel conductors, typically red and black, designed for low-voltage audio signals.
It is not suitable for control, data, or power transmission due to its lack of shielding and insulation properties.
Avoid using speaker cable in gate or security installations as it can lead to faults, interference, and premature failure.
3. Best Practice & Installation Tips
Double up cores for long runs on low voltage DC applications (e.g. red + yellow together on GSM supply)
Always use black sheathed cable outdoors for UV resistance
Bring cables into enclosures from the bottom only (prevents water ingress)
Protect cables on posts with 20mm conduit
Silicon-seal cable entries
Pre-wire, label, and test all cable runs before final installation
4. Why Cable Choice Matters
Correct cabling = long life and fewer call-backs
Prevents failures caused by water ingress or UV damage
Maintains compliance with UK wiring regs & safety standards
Protects sensitive electronics (e.g. GSM, intercom boards) from interference
Saves time in future upgrades — extra cores = no re-pulling
5. Application Quick Reference
Typical Cable Types for Gate Automation Installations
230V Supply:
Use 3-core SWA cable for mains power feeds. A 2.5mm² core size is suitable for runs under 100 metres. The steel wire armouring provides mechanical protection, making it ideal for underground or external routes.24V Motor Cable:
Use a flexible 2- or 3-core 2.5mm duct-grade cable for low-voltage motor connections. It should be durable, moisture-resistant, and suitable for movement or vibration where required. Motors with encoders often require extra cores. We like to use a single cable with enough cores rather than running extra cables which is less tidy.230v Motor Cable: Use black rubber flex 2.5mm, 4 cores as this cable is continuously moving, the rubber remains flexible and prevents cracking.
Intercom or CCTV:
Use duct-grade Cat5e or Cat6 cable that is safe for direct burial. These cables provide high-quality data transmission and are protected against moisture and UV exposure. A SWA Cat6 is available.All low voltage accessories :
8-core cable, duct-grade or Direct burial for added protection against moisture and physical damage. These cables carry low-voltage signal connections between control devices.Data Cables in Ducts:
Use duct-grade Cat5e or Cat6 for all data and network runs in underground ducts. Always pull through spare cables during installation to allow for future expansion or replacements without re-excavation.Mains and 12v cables should be routed separately for safery and signal shielding
6. Common Cable Mistakes
🚫 Using indoor-only (white sheathed) cables outdoors
🚫 Burying non-rated cable directly without ducting
🚫 Running Cat5 alongside 230V without shielding → causes interference
🚫 Cutting cables too short → no service loop left
🚫 Mixing cable types mid-run (e.g. Cat5 with duct-grade Cat5)
7. Safety Notes & SSOW
Always assume underground cables are live until proven otherwise
SWA must be earthed correctly at both ends for safety
Direct-buried cables should be at least 450mm deep with warning tape above
Avoid using non-rated cables outdoors — risk of insulation breakdown & fire
Follow the site-specific Safe System of Work (SSOW) for excavation and cable laying
Never share ducts between data cables and 230V mains unless rated and separated properly
