CCTV leads: BNC, Siamese & Power Cables for Reliable Surveillance

Why the right CCTV leads matter for performance and uptime

Choosing the correct CCTV leads (video, power and hybrid cables) affects picture quality, noise, and camera reliability more than many installers realise. We focus on practical outcomes: low-noise video, correct voltage at the camera, easy routing, and serviceable terminations - all sourced from local stock to avoid project delays.

Common CCTV lead types and where to use them

• RG59 / RG6 coaxial: standard for analogue BNC systems; shorter runs and simple installations.
• Siamese cable (coax + twin power): popular for analogue and HD-analogue installs to carry video and 12V/24V in one sheath.
• UTP with baluns (Cat5/6): cost-effective for long runs or when using IP encoders or video baluns.
• DC power cables (2.1/5.5 barrel-compatible cores): sized to minimise voltage drop to the camera.
• POE cables (Cat5e/6): for IP cameras, combining data and power over a single cable where POE switches or injectors are used.

If you're not sure where to start, compare categories in our Collections or browse brands on our Shop by Brand page for components commonly used in surveillance installations.

Specification quick-check: what to compare

Before ordering, verify these cable specs against the camera and installation plan to avoid rework and downtime.

Real-world example: choosing a lead for a 100 m dome camera run

Scenario: 12 V dome camera, 250 mA consumption, 100 m cable run. To keep voltage drop under 10% (1.2 V): use Ohm's law and cable resistance.

Calculation (simplified): Vdrop = I x R. For 18 AWG twin power, approximate resistance ~0.021 ohm/m. Round trip = 200 m. Vdrop = 0.25 A x (0.021 x 200) = 1.05 V (acceptable). If using 22 AWG, resistance is higher and Vdrop may exceed 1.2 V; choose thicker conductor or POE solution.

For IP cameras, prefer Cat6 for future-proofing and easier POE delivery. See compatible product ranges in our buy-cctv-leads index.

Installation notes, terminations and troubleshooting

Wiring examples and termination tips

Clean terminations reduce noise and service calls. For BNC ends, use crimp or compression connectors sized for your coax. For Siamese cables, separate cores and use heat-shrink to protect splices. For POE, terminate Cat6 with a quality RJ45 connector or keystone jack and test with a POE tester.

Wiring diagram (Siamese to camera)Power supply (+) ---- red core ----> camera +12VPower supply (-) ---- black core ----> camera GNDCoax centre conductor ----> camera BNC centre pinCoax shield ----> camera BNC outer shell

Common issues and fixes

• Intermittent video: check BNC continuity and shield integrity; replace poor crimps.
• Dark or dim image: verify voltage at camera under load and upgrade power conductor if drop exceeds recommendation.
• Hum or noise on video: add grounded shielding or switch to higher-grade coax/UTP with baluns.

If a problem persists, bring a sample cable and affected camera to our Samrand branch for hands-on diagnostics; see our Branches & Trading Hours for collection and walk-in testing.

Why buy CCTV leads from Communica in South Africa

We hold local stock on common CCTV leads and accessories so projects stay on schedule. Benefits installers and procurement teams cite: predictable availability, VAT invoices for tendering, branch pickup to avoid courier delays, and knowledgeable staff who advise on conductor sizing and PoE requirements. For background on our company and service approach, read about us on the About Us page.

Spec callouts, accessory bundles and next steps

When ordering, bundle leads with connectors, adhesive cable clips, and a voltage tester to reduce site visits. Use the following quick checklist when requesting a quote: cable type, run length, camera supply voltage, POE or DC, and required connector type. Mention these details in a Collections enquiry to get a tailored parts list and delivery estimate.

We understand project timelines in South Africa can change - leverage branch collection, request a quote for bulk requirements, or compare specs in-store to confirm fit. Shop Now, Check Stock in Samrand, Compare Specs or Request a Quote to progress your installation with confidence.