Cable and Connector Selection for Industrial Use

Understanding the Critical Role of Cables and Connectors in Industrial Applications

In the demanding industrial environments found throughout Atlantic Canada—from fish processing plants in Lunenburg to manufacturing facilities in Moncton and offshore energy operations in Halifax—the selection of appropriate cables and connectors can mean the difference between reliable operations and costly downtime. These seemingly simple components form the nervous system of modern industrial systems, transmitting power, data, and control signals that keep operations running smoothly.

Industrial cable and connector selection requires careful consideration of numerous factors, including electrical specifications, environmental conditions, mechanical stresses, and regulatory compliance. For facilities operating in Nova Scotia's varied climate, where temperatures can swing from -25°C in winter to humid summer conditions exceeding 30°C, choosing the right components becomes even more critical.

This comprehensive guide explores the essential considerations for selecting industrial cables and connectors, providing engineers and technical managers with the knowledge needed to make informed decisions that enhance system reliability and longevity.

Electrical Specifications and Performance Requirements

The foundation of any cable and connector selection process begins with understanding the electrical requirements of your application. Getting these specifications wrong can result in system failures, safety hazards, and regulatory non-compliance.

Voltage and Current Ratings

Industrial applications typically operate across a wide voltage range, from low-voltage control circuits at 24V DC to medium-voltage power distribution at 5kV or higher. When selecting cables, always choose products rated for at least 125% of your maximum operating voltage to provide an adequate safety margin.

Current-carrying capacity, or ampacity, must account for:

• Continuous operating current – the steady-state current the cable must carry

• Inrush currents – temporary high currents during motor starting or capacitor charging

• Ambient temperature derating – reduced capacity in high-temperature environments

• Installation method derating – cables in conduit or bundles carry less current than open-air installations

• Altitude considerations – reduced air density at higher elevations affects cooling

For example, a 10 AWG copper conductor rated at 30A in free air at 30°C may only safely carry 24A when installed in conduit with other current-carrying conductors at 40°C ambient temperature.

Signal Integrity and Shielding Requirements

Industrial environments present significant electromagnetic interference (EMI) challenges. Variable frequency drives, welding equipment, and high-power switching devices generate noise that can corrupt sensitive control and data signals. Proper shielding selection is essential:

• Foil shields – provide 100% coverage and effective high-frequency noise rejection, ideal for data cables

• Braided shields – offer superior low-frequency protection and better flex life, typically providing 85-95% coverage

• Combination foil/braid shields – deliver comprehensive protection across the frequency spectrum for demanding applications

• Drain wires – ensure proper shield termination and grounding continuity

For industrial Ethernet applications common in modern facilities, Cat6A shielded cables with individually shielded pairs (S/FTP) provide reliable 10 Gigabit performance even in electrically noisy environments.

Environmental Considerations for Maritime and Industrial Settings

Atlantic Canada's industrial facilities face unique environmental challenges that significantly impact cable and connector selection. Understanding these factors is essential for specifying components that will perform reliably throughout their intended service life.

Temperature Extremes and Thermal Cycling

Nova Scotia experiences significant temperature variations throughout the year. Industrial facilities may see even greater extremes, from freezer storage areas at -40°C to boiler rooms exceeding 60°C. Standard PVC-jacketed cables typically operate reliably only between -10°C and 60°C, making them unsuitable for many applications.

For extended temperature ranges, consider:

• Thermoplastic elastomer (TPE) jackets – operating range of -50°C to 105°C

• Silicone-insulated cables – exceptional flexibility at low temperatures and heat resistance to 200°C

• XLPE (cross-linked polyethylene) insulation – excellent thermal stability and moisture resistance

• FEP and PTFE insulations – premium performance from -65°C to 260°C for extreme applications

Connectors must also withstand thermal cycling without seal degradation. Look for connectors with silicone or fluorosilicone seals rated for your temperature extremes, and consider thermal expansion differences between mating materials.

Moisture, Salt, and Chemical Exposure

Coastal industrial facilities throughout the Maritimes face constant exposure to salt-laden air and high humidity. Processing plants handle various chemicals that can degrade standard cable materials. Proper material selection is critical:

• Polyurethane jackets – excellent abrasion and chemical resistance, ideal for manufacturing environments

• CPE (chlorinated polyethylene) jackets – superior oil and chemical resistance for petrochemical applications

• Stainless steel connector housings – 316 stainless steel provides optimal corrosion resistance in marine environments

• Gold-plated contacts – prevent oxidation and ensure reliable connections in humid conditions

• IP-rated enclosures – IP67 minimum for washdown areas, IP69K for high-pressure cleaning environments

UV Resistance for Outdoor Installations

Outdoor cable runs require UV-stabilised jacket materials to prevent degradation from solar exposure. Black polyethylene and specially formulated PVC compounds offer good UV resistance, while untreated cables can become brittle and crack within just two to three years of outdoor exposure.

Mechanical Considerations and Durability

Industrial cables and connectors must withstand significant mechanical stresses throughout their service life. Understanding these requirements helps prevent premature failures and unplanned maintenance.

Flexing and Motion Applications

Robotic systems, cable carriers, and moving machinery require cables specifically designed for continuous flexing. Standard cables will fail rapidly in these applications—sometimes within weeks. Flex-rated cables incorporate design features that dramatically extend service life:

• Stranded conductors with high strand counts – 7x7 (49 strands) or higher constructions for continuous flex

• Lay length optimisation – proper twist rates prevent conductor bunching during flexing

• Slip-plane jacket designs – allow internal components to move independently

• Flex life ratings – premium cables are tested to 10 million flex cycles or more

For cable carrier applications, select cables rated for the specific bend radius and travel speed of your system. A typical cable carrier application might require cables rated for a minimum bend radius of 7.5 times the cable diameter at travel speeds up to 3 metres per second.

Vibration and Impact Resistance

Heavy machinery, compressors, and transportation equipment subject cables and connectors to continuous vibration. Connector selection for these applications should prioritise:

• Threaded coupling mechanisms – superior vibration resistance compared to bayonet or push-pull designs

• Positive locking features – secondary retention mechanisms prevent accidental disconnection

• Strain relief systems – properly sized cable glands and backshells protect termination points

• Vibration-resistant contact designs – spring-loaded or hyperboloid contacts maintain connection integrity

Connector Types and Selection Criteria

The industrial connector market offers numerous options, each designed for specific applications. Selecting the appropriate connector family simplifies installation, ensures compatibility, and provides the performance characteristics your application demands.

Circular Connectors

Circular connectors dominate industrial applications due to their robust construction and versatile configurations:

• M12 connectors – the industrial automation standard, available in 3 to 12-pin configurations with A, B, D, and X codings for different protocols

• M8 connectors – compact alternative for space-constrained sensor applications

• M23 connectors – larger format for servo motor and high-power applications, supporting up to 28 contacts

• 7/8" connectors – heavy-duty power connections rated up to 16A per contact

For industrial Ethernet applications, M12 X-coded connectors support Cat6A performance for 10 Gigabit networking, while D-coded versions handle standard 100 Mbps requirements.

Rectangular and Specialty Connectors

Heavy-duty rectangular connectors (HDC) offer modular flexibility for complex interface requirements:

• Modular insert systems – combine power, signal, data, and pneumatic connections in a single housing

• Hot-swappable designs – enable equipment changes without system shutdown

• High-density configurations – up to 216 contacts in a single connector

• High-current modules – individual contacts rated to 200A for power distribution

Fibre Optic Connectors

For applications requiring immunity to electromagnetic interference or long-distance data transmission, industrial fibre optic connectors provide reliable solutions:

• LC connectors – small form factor with excellent performance for high-density applications

• SC connectors – robust push-pull design popular in industrial networks

• Industrial ruggedised variants – IP67-rated versions of standard connector types

• Expanded beam connectors – tolerant of contamination and misalignment in harsh environments

Compliance, Standards, and Certification Requirements

Industrial cables and connectors must meet various regulatory requirements depending on their application and installation location. Understanding these requirements ensures compliant installations and facilitates inspections.

Canadian Electrical Code and Standards

All electrical installations in Nova Scotia must comply with the Canadian Electrical Code (CEC) and provincial amendments. Key considerations include:

• CSA certification – required for cables and connectors used in permanent installations

• Flame ratings – FT4 or FT6 ratings for plenum and riser applications

• Hazardous location ratings – Class I, II, or III Division ratings for explosive atmospheres

• cUL listing – ensures compliance with Canadian safety standards

Industry-Specific Requirements

Various industries impose additional requirements:

• Food and beverage – NSF-certified cables and stainless steel connectors for product contact areas

• Oil and gas – NRTL certification for hazardous locations, often requiring armoured cables

• Marine and offshore – DNV, Lloyd's, or ABS type approval for shipboard installations

• Mining – MSHA approval for underground mining applications

Installation Best Practices and Maintenance Considerations

Even the best cables and connectors will fail prematurely if improperly installed or maintained. Following industry best practices maximises system reliability and service life.

Installation Guidelines

Proper installation practices include:

• Bend radius compliance – never exceed the manufacturer's minimum bend radius, typically 6 to 10 times the cable diameter

• Pulling tension limits – observe maximum pulling forces to prevent conductor damage

• Proper support spacing – support cables at intervals recommended by the manufacturer to prevent jacket stress

• Separation from interference sources – maintain appropriate distances from power cables and noise sources

• Correct torque specifications – use calibrated tools for connector assembly

Maintenance and Inspection

Regular inspection programmes help identify developing problems before they cause failures:

• Visual inspections – check for jacket damage, corrosion, and proper strain relief

• Thermal imaging – identify hot spots indicating high-resistance connections

• Insulation resistance testing – verify cable insulation integrity

• Contact resistance measurement – ensure connector contacts maintain proper resistance values

Partner with Atlantic Canada's Engineering Experts

Selecting the right cables and connectors for your industrial application requires balancing numerous technical, environmental, and regulatory factors. Making informed decisions at the specification stage prevents costly failures and ensures your systems perform reliably for years to come.

Sangster Engineering Ltd., based in Amherst, Nova Scotia, brings decades of electronics engineering expertise to industrial projects throughout Atlantic Canada. Our team understands the unique challenges facing Maritime industries—from the corrosive salt air of coastal facilities to the demanding requirements of manufacturing and processing operations.

Whether you're designing a new control system, upgrading existing infrastructure, or troubleshooting reliability issues, our engineers can help you select and specify cables and connectors optimised for your specific application. We provide comprehensive engineering services, from initial consultation and system design through to implementation support and documentation.

Contact Sangster Engineering Ltd. today to discuss your cable and connector requirements. Let our expertise help you build more reliable, efficient industrial systems that stand up to the demands of your operation and the Atlantic Canadian environment.

Partner with Sangster Engineering

At Sangster Engineering Ltd. in Amherst, Nova Scotia, we bring decades of engineering experience to every project. Serving clients across Atlantic Canada and beyond.

Contact us today to discuss your engineering needs.