Industrial Automation: Building a Certification Lab Strategy

Industrial automation equipment faces unique certification challenges: machinery safety directives, functional safety requirements, EMC in harsh environments, and cybersecurity for connected systems. Here's how to build a lab testing strategy that addresses these complexities.

Understanding Industrial Automation Compliance

Industrial automation equipment—PLCs, HMIs, industrial robots, motor drives, sensors—must comply with the EU Machinery Directive (2006/42/EC), EMC Directive, and often functional safety standards like IEC 61508 or ISO 13849. In the US, OSHA regulations and NFPA 79 (Electrical Standard for Industrial Machinery) apply.

The complexity stems from the interaction between hardware, software, and mechanical systems. A robotic arm isn't just an electrical device—it's a machine that must prevent mechanical hazards (crushing, shearing, entanglement) while also meeting electrical safety and EMC requirements.

Machinery Safety and Risk Assessment

The Machinery Directive requires a comprehensive risk assessment identifying all hazards and implementing appropriate risk reduction measures. This assessment drives your testing strategy and determines which harmonized standards apply to your equipment.

Key Risk Assessment Steps:

• Identify all reasonably foreseeable hazards (mechanical, electrical, thermal, noise, vibration)
• Estimate risk for each hazard (severity × probability)
• Implement risk reduction measures (inherently safe design, guards, warnings)
• Document residual risks and protective measures
• Validate that risk reduction measures are effective

Functional Safety Testing Strategy

Industrial automation often requires functional safety—the ability of safety-related systems to respond correctly to dangerous conditions. IEC 61508 provides the framework for functional safety across all industries, while sector-specific standards (ISO 13849 for machinery, IEC 62061 for machine control systems) provide detailed requirements.

Functional safety testing goes beyond traditional compliance testing. It requires validation of safety functions, fault detection mechanisms, diagnostic coverage, and systematic capability. This typically involves:

Functional Safety Test Requirements:

• Safety function validation (emergency stop, safety interlocks, protective stops)
• Fault injection testing (verify system responds correctly to component failures)
• Diagnostic coverage analysis (measure effectiveness of self-diagnostics)
• Software safety validation (per IEC 61508-3 or ISO 13849-1)
• Systematic capability assessment (design process, documentation, verification)

EMC Testing in Industrial Environments

Industrial environments are electrically harsh: motor drives generate high-frequency noise, welders create transients, and long cable runs act as antennas. EMC testing for industrial equipment must address these real-world conditions.

The industrial EMC standard (IEC 61000-6-2 for immunity, IEC 61000-6-4 for emissions) sets more stringent requirements than consumer product standards. Industrial equipment must withstand higher levels of electrical fast transients, surge, and conducted disturbances.

Critical EMC Tests for Industrial Automation:

• Electrical Fast Transient (EFT/Burst): Tests immunity to switching transients from contactors and relays
• Surge immunity: Validates protection against lightning and switching surges
• Conducted immunity: Ensures equipment operates correctly with RF noise on power and signal lines
• Radiated immunity: Tests resistance to RF fields from wireless devices and industrial equipment
• Voltage dips and interruptions: Validates ride-through capability during power quality events

Selecting the Right Testing Labs

Not all labs have expertise in industrial automation. Look for labs with specific accreditations and experience in your product category.

Key Lab Qualifications:

• Accreditation for machinery testing (TÜV, UL, CSA, Intertek)
• Functional safety expertise (IEC 61508, ISO 13849, IEC 62061)
• Industrial EMC testing capability (higher power levels, specialized test setups)
• Mechanical testing facilities (impact, vibration, environmental)
• Software assessment capability for safety-critical code

Documentation Requirements

Industrial automation equipment requires extensive technical documentation. The Machinery Directive mandates a Technical Construction File that includes:

• Overall drawing of the machinery and control circuit diagrams
• Risk assessment and list of essential health and safety requirements
• Standards applied and description of solutions adopted
• Technical reports and test certificates
• Instruction manual with safety information
• Declaration of conformity or incorporation

Cybersecurity for Connected Industrial Systems

Industrial IoT and Industry 4.0 initiatives connect automation equipment to enterprise networks and cloud platforms. This connectivity introduces cybersecurity risks that must be addressed during certification.

IEC 62443 provides a comprehensive framework for industrial automation cybersecurity. The standard covers secure development practices, network segmentation, access control, and security testing. Many customers now require IEC 62443 compliance as a procurement requirement.

Cybersecurity Testing Considerations:

• Penetration testing of network interfaces and protocols
• Authentication and access control validation
• Secure firmware update mechanisms
• Data encryption for storage and transmission
• Security event logging and monitoring
• Vulnerability assessment and remediation

Building Your Lab Testing Timeline

Industrial automation certification typically takes 6-12 months from design freeze to market launch. This timeline includes:

• Risk assessment and standards mapping: 4-6 weeks
• Design for compliance review: 4-6 weeks
• Pre-compliance testing (EMC, safety, functional): 6-8 weeks
• Formal certification testing: 12-16 weeks
• Technical file preparation and review: 6-8 weeks
• Notified Body assessment (if required): 8-16 weeks

For equipment requiring functional safety certification (SIL 2 or higher), add 3-6 months for safety assessment and validation.