12 types of cables and how to choose them

Alright, let's talk about the unsung heroes of our modern world: electrical cables. You see them everywhere – hidden in walls, snaking through industrial plants, or connecting our favorite devices. But have you ever stopped to think about how many different types there are or how to pick the perfect one?

Whether you're doing a DIY project at home or an electrical pro, choosing the right cable isn't just about getting power from point A to point B. It's about safety, efficiency, and making sure things actually work the way they should. Let's break down the 12 most common cable types and the simple principles to choose wisely.

The Everyday Squad (Home & Office Use)

1. Non-Metallic Sheathed Cable (NM Cable/Romex)

This is your typical household wiring superhero. Picture that yellow or white cable you might've seen during renovations. It's got multiple insulated wires (usually two to four) wrapped in a plastic sheath that's easy to handle and install. Perfect for dry indoor spaces like your living room walls or attic.

Use it when: Wiring outlets, switches, and lights in dry indoor areas. Not for wet locations or outdoors!

2. Armored Cable (BX Cable)

Think of this as Romex's tougher cousin. Instead of plastic, it's got a flexible metal sheath that acts like armor against physical damage. The cool part? That metal sheath doubles as the grounding path. You'll see this in places where cables might get bumped or exposed – like unfinished basements or industrial settings.

Use it when: Running wires through crawl spaces or areas where mice might mistake cables for chew toys.

3. Underground Feeder Cable (UF Cable)

This is NM cable's weatherproof sibling. With extra-thick insulation and moisture resistance, it laughs in the face of rain and soil. You can literally bury it directly underground without extra piping – no wonder it's perfect for garden lights, sprinkler systems, or powering that backyard workshop.

Use it when: Any outdoor wiring exposed to weather or direct burial. The "U" stands for "underground"!

The Data Dynamos (Communication & Tech)

4. Coaxial Cable

That thick, round cable connecting your TV to the wall? That's coaxial. Inside, there's a copper core wrapped in layers of insulation and shielding that blocks interference. What makes it special? It can carry cable TV signals, internet, and video without quality loss. You'll see versions like RG-6 for modern HD setups and RG-59 for older installations.

Use it when: Connecting antennas, satellite dishes, or cable modems – anywhere video signals need clear paths.

5. Twisted Pair Cable

This is the quiet workhorse behind your internet and phone systems. Inside, you'll find pairs of color-coded wires twisted together like DNA strands – this clever design cancels out electromagnetic noise. Comes in unshielded (UTP, your standard Ethernet) and shielded (STP, for noisy industrial spots).

Use it when: Networking computers, phones, or security systems. Cat5e/Cat6 are household names for a reason.

6. Fiber Optic Cable

Welcome to the speed kings! Instead of metal, these cables send data as light pulses through hair-thin glass fibers. The result? Blazing-fast speeds over long distances without signal loss. You'll see single-mode fibers for long-haul telecom and multi-mode for in-building networks. They're revolutionizing high-speed communication globally.

Use it when: You need high bandwidth – think data centers, cable TV backbones, or hospitals transferring MRI images.

The Tough Guys (Industrial & Specialized)

7. High-Temperature Cable

Imagine your oven's wiring – regular plastic insulation would melt in seconds. These cables use special materials (like silicone or Teflon®) that shrug off extreme heat. Found in furnaces, boilers, foundries, and high-power lighting fixtures.

Use it when: Temperatures regularly hit 150°C+ (300°F+). Don't gamble with standard cables here!

8. Metal-Clad Cable (MC Cable)

Think armored cable but industrial grade. Has full metal armor plus an additional ground wire inside. Handles extreme mechanical abuse like factory machinery vibrations and heavy equipment impacts.

Use it when: Commercial buildings with complex systems or industrial settings with conveyor belts.

9. Vulcanized Rubber Cable

These veterans use natural or synthetic rubber insulation – incredibly flexible and resilient. Perfect for moving equipment like robotic arms and machinery maintenance lights.

Use it when: Equipment needs repeated flexing without degrading. The OG choice for mobile industrial gear.

The Backstage Heroes

10. THHN/THWN Cable

These letters actually mean something! THHN stands for Thermoplastic High Heat-resistant Nylon-coated – the versatile single conductors in metal conduit you see at hardware stores. THWN adds Water Resistance. Perfect for indoor conduits and commercial wiring harnesses.

Use it when: Running wires through conduit pipes where moisture might sneak in.

11. Service Entrance Cable (SE Cable)

This heavy-duty cable connects your main electrical panel to the utility company's lines. Designed to handle large current from the power grid.

Use it when: Connecting your home or building to the utility meter.

12. Submersible Cable

Ever wonder what powers deep-well water pumps? These cables are waterproof wonders designed to handle constant immersion under pressure without shorting.

Use it when: Wiring underground water pumps or marine equipment. Regular cables fail miserably here!

How to Choose the Right Cable: No PhD Required!

Alright, you've seen the lineup. But how do you pick? It's simpler than you think – just ask these five questions:

1. What's Your Power Load?

Calculate your current needs (amps): Take total wattage of devices, add 20% for future expansion, divide by voltage (usually 120V/240V). For example:
5300W kitchen × 1.2 = 6360W ÷ (240V × 0.9 power factor) = ~32A

2. Environment Matters!

Is it:

Dry or damp? Use NM indoors, UF for outdoors/dampness
Hot? Only high-temp cables survive near furnaces
Exposed to movement? Use flexible cables to avoid cracks
Buried or submerged? Only UF or submersible types survive

3. Voltage ｄｒｏｐ - The Silent Killer

Ever wonder why distant motors run slow? Power loss! Every cable resists electrical flow. For runs over 30 meters:
Voltage ｄｒｏｐ = Current × Cable Resistance × Length
Keep it under 3% to prevent equipment damage and efficiency loss. Pro tip: Choose thicker cables for long distances.

4. Safety First!

Never compromise on:

Insulation ratings: Must match voltage requirements
Fire resistance: Critical for high-rise buildings
Grounding: Required for any metallic-sheathed cable

5. Decoding Cable Labels

Those markings aren't random:

VDE: German safety certification
NYY: PVC-insulated/pvc-sheathed power cables
RM numbers: Indicate conductor size (e.g., 10RM handles ~46A)
Temperature ratings: 90°C vs 60°C makes a huge difference!

Quick Reference Guide

Cable Type	Best For	Voltage Range	Max Temp
NM Cable	Dry indoor wiring	600V	90°C
UF Cable	Buried outdoor lines	600V	75°C
BX Cable	Exposed areas	600V	90°C
Coaxial	Video/data signals	Low voltage	80°C
Fiber Optic	Long-range data	N/A (light)	70°C
High-Temp	Ovens/furnaces	600V	200°C

Wrapping It Up

Think of cables like the veins of any electrical system – the right choice keeps everything running smoothly, while the wrong one creates headaches or dangers. Whether you're running standard NM cables through drywall or specialized power cables through industrial settings, remember:

Always oversize a bit: That 20% extra capacity avoids future rewiring
Respect the environment: Outdoor ≠ indoor cables!
Consult local codes: Regulations vary – especially for service entrance wiring
When in doubt, ask a pro: Some jobs shouldn't be DIY adventures

Next time you see cables running through walls or ceilings, you'll know there's an entire ecosystem of specially designed wires working behind the scenes. The right choice means safety, efficiency, and trouble-free power for years to come!