Cabling & Termination

Choosing the right cable:

Power Cables:

Building Wire:
- THHN/THWN: Most common building wire
- XHHW: Wet locations, higher temperature
- MTW: Machine tool wire (panels)
- Use-rated: Stranded or solid

Industrial Cables:
- SO/SOW: Flexible cord, portable equipment
- MC Cable: Metal clad, quick installation
- TC Tray Cable: Cable trays, flexible
- VFD Cable: Shielded for drive applications

Conductor Materials:
- Copper: Higher conductivity, standard
- Aluminum: Lighter, lower cost, larger for same current
- Tin-plated: Corrosion resistance

Control and Signal Cables:

Instrumentation:
- Twisted pair: Noise rejection
- Shielded: EMI protection
- Multi-pair: Multiple signals in one jacket
- Color coding per pair

Thermocouple:
- Extension wire matches thermocouple type
- Compensating cable for long runs
- Temperature-rated insulation

Communication:
- Ethernet: Cat5e, Cat6, Cat6A
- Industrial Ethernet: Oil-resistant, flexible
- Fiber optic: Single-mode, multi-mode
- Coaxial: Legacy applications

Cable Ratings:

Voltage:
- 600V: Standard for most industrial
- 1000V: Some VFD cables
- Medium voltage: 5kV+, special termination

Temperature:
- 60C, 75C, 90C ratings
- Ampacity depends on rating
- Higher temp = higher current

Environment:
- Wet locations
- Oil/chemical resistance
- Sunlight resistance (UV)
- Direct burial

Sizing:
- NEC ampacity tables
- Voltage drop calculations
- Derating factors
- Future capacity

Making reliable connections:

Compression Connectors:

Ring/Spade Terminals:
- Crimped onto wire
- Screwed to terminal
- Standard for stranded wire
- Size matched to wire and screw

Ferrules:
- Crimped onto stranded wire
- Prevents strand damage
- Required for spring terminals
- DIN rail terminal standard

Compression Lugs:
- Large cables
- One or two-hole mounting
- Proper crimping tool essential
- Color-coded by wire size

Proper Crimping:
- Correct die for terminal
- Full compression
- No exposed strands
- Verify crimp quality

Screw Terminals:

Types:
- Binding head screws
- Terminal blocks
- Set screw connectors
- Compression plates

Best Practices:
- Proper torque (check specs)
- Wire wrap direction (clockwise)
- No insulation in terminal
- Strain relief on cable

Spring/Push-In Terminals:

Types:
- Push-in (solid wire only)
- Spring clamp (any wire with ferrule)
- Lever-operated
- Tool-less connection

Advantages:
- Faster installation
- Consistent connection force
- Vibration resistant
- No torque maintenance

Soldering:

When Used:
- Electronics
- Some instrumentation
- Repair of stranded wire
- Terminal lugs (less common)

Industrial Concerns:
- Time-consuming
- Skill-dependent
- Cold joint failures
- Generally avoided for power

Professional cable installation:

Routing:

Separation:
- Power and signal separate
- Minimum distances per code
- Cross at right angles
- Separate raceways

Support:
- Proper spacing per cable type
- No sharp edges
- Adequate bend radius
- Secure but not over-tight

Cable Tray:
- Fill limits (40-50% typical)
- Cover when required
- Grounding per NEC
- Separation barriers

Conduit:
- Fill calculations
- Pull tension limits
- Expansion fittings
- Proper fittings at boxes

Wire Management:

Panel Wiring:
- Wire duct sizing
- Neat bundling
- Service loops
- Logical routing

Field Wiring:
- Junction box placement
- Identification labels
- Weatherproofing
- Access for maintenance

Labeling:

Wire Identification:
- Both ends labeled
- Match drawings
- Durable labels
- Machine printed preferred

Cable Marking:
- Circuit identification
- Destination/source
- Cable type/size
- Warning labels

Environmental Protection:

Outdoor:
- UV-rated cables
- Weatherproof boxes
- Drainage provisions
- Corrosion prevention

Industrial:
- Oil/chemical resistance
- Mechanical protection
- Temperature considerations
- Vibration resistance

Verifying installations and career paths:

Testing Methods:

Continuity:
- Verify complete circuit
- Check before energizing
- Low-ohm range
- Test both directions

Insulation Resistance:
- Megger testing
- Minimum values per voltage
- Test phase-to-phase and phase-to-ground
- Document results

Hi-Pot Testing:
- High voltage testing
- Above normal operating voltage
- Factory or critical applications
- Special equipment and safety

Cable Certification:
- Communication cables
- Performance verification
- Document and label
- Fluke and similar testers

Quality Indicators:

Good Installation:
- Neat, organized routing
- Proper terminations
- Complete labeling
- Documentation

Problems to Avoid:
- Tight bend radius
- Over-stretched cables
- Damaged insulation
- Loose connections

Career Opportunities:

Electrician Apprentice:
Learn fundamentals:
- Cable pulling
- Basic termination
- Code compliance
- $35,000-$50,000

Journeyman Electrician:
Full installation capability:
- All termination methods
- Troubleshooting
- Code expertise
- $55,000-$85,000

Master Electrician:
Design and supervision:
- Project management
- Code authority
- Estimating
- $70,000-$100,000

Cable Technician:
Specialty focus:
- Data/communication cabling
- Certification testing
- Network infrastructure
- $45,000-$70,000

Skills Development:

Fundamentals:
- Cable types and applications
- Termination techniques
- Code requirements
- Tool proficiency

Practice:
- Repetition builds skill
- Speed comes with accuracy
- Learn from experienced workers
- Inspect your own work critically

Certifications:
- BICSI (data cabling)
- Electrical license
- Vendor certifications

Quality termination skills are fundamental to all electrical work.