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IEC 10026-6-00:2004 – Electrical Safety and Electromagnetic Compatibility Requirements for Industrial Control Systems
A Comprehensive Guide to Scope, Technical Specifications, and Compliance Pathways
1. Scope and Application
IEC 10026-6-00:2004 is part of the IEC 10026 series that specifies safety and EMC requirements for industrial control equipment and systems. This standard applies to electrical/electronic equipment used in control and automation systems, including but not limited to programmable logic controllers (PLCs), distributed control systems (DCS), variable speed drives, and associated peripheral devices. The standard covers equipment with a rated supply voltage not exceeding 1000 V AC or 1500 V DC, intended for use in industrial environments as defined in IEC 61000-6-2.
2. Technical Requirements
2.1 Insulation Coordination
The standard mandates insulation coordination based on IEC 60664-1. Equipment is categorized by overvoltage categories (I to IV) and pollution degrees (1 to 4). The table below provides the minimum clearance distances required for basic insulation at different overvoltage categories and pollution degree 2.
| Rated Impulse Withstand Voltage (kV) | Clearance for Overvoltage Category II (mm) | Clearance for Overvoltage Category III (mm) |
|---|---|---|
| 0.5 | 0.2 | 0.5 |
| 1.0 | 0.5 | 1.0 |
| 2.5 | 1.5 | 2.5 |
| 4.0 | 3.0 | 5.0 |
| 6.0 | 5.5 | 8.0 |
2.2 Protection Against Electric Shock
Both direct and indirect contact are addressed. Requirements include:
- Enclosure protection (IP rating) and clearance to live parts.
- Equipotential bonding and grounding of conductive parts.
- Use of protective devices such as RCDs and fuses according to IEC 60364.
2.3 Electromagnetic Compatibility (EMC)
Equipment must comply with emission limits according to CISPR 11 (for industrial emissions) and immunity requirements according to IEC 61000-6-2. Key tests include:
- Electrostatic discharge (IEC 61000-4-2).
- Radiated and conducted RF immunity (IEC 61000-4-3 and 4-6).
- Fast transients (IEC 61000-4-4).
- Surge and voltage dips (IEC 61000-4-5 and 4-11).
Tip: Use ferrite beads and shielded cables to mitigate conducted emissions and improve immunity performance.
3. Testing and Verification
Verification of compliance with IEC 10026-6-00 involves type testing and possibly routine testing. The following tests are mandatory:
- Dielectric strength test: applied between live parts and accessible conductive parts at 2U+1000 V (minimum 1.5 kV) for 1 minute.
- Insulation resistance test: minimum 1 MΩ at 500 V DC.
- EMC tests as per the referenced standards.
- Protective bonding resistance test: <0.1 Ω.
4. Compliance and Certification Pathways
Manufacturers must compile a technical file demonstrating compliance. Key steps:
- Identify applicable requirements based on equipment category.
- Design and test product against these requirements.
- Obtain a test report from an accredited laboratory (e.g., IECEE CB scheme).
- Issue a Declaration of Conformity (DoC) and affix the mark of conformity (e.g., CE, UKCA, or others).
Warning: EMC compliance is often underestimated. Pre-compliance scanning can reduce costly redesigns.
Success: Many global markets accept IEC 10026-6-00 as a basis for national regulations, streamlining market access.
Danger: Using components not rated for the required overvoltage category can cause insulation breakdown and arcing.
5. Frequently Asked Questions
Q: Is IEC 10026-6-00 independent of IEC 61508 (functional safety)?
A: Yes, IEC 10026-6-00 focuses on basic electrical safety and EMC, while IEC 61508 addresses functional safety. Both may apply simultaneously; they are not substitutable.
A: Yes, IEC 10026-6-00 focuses on basic electrical safety and EMC, while IEC 61508 addresses functional safety. Both may apply simultaneously; they are not substitutable.
Q: Does this standard apply to equipment installed in hazardous areas?
A: No, for hazardous areas, standards like IEC 60079 series take precedence. However, equipment intended for safe area installation adjacent to hazardous areas may still require additional mitigation.
A: No, for hazardous areas, standards like IEC 60079 series take precedence. However, equipment intended for safe area installation adjacent to hazardous areas may still require additional mitigation.
Q: How should I handle legacy equipment not designed to this standard?
A: Retrofit or replacement may be required to meet legal obligations for new installations. Risk assessment per ISO 12100 can help determine necessary retrofits.
A: Retrofit or replacement may be required to meet legal obligations for new installations. Risk assessment per ISO 12100 can help determine necessary retrofits.
Q: What are the implications of using this standard in a low-voltage directive (LVD) context?
A: IEC 10026-6-00 can be used as a presumption of conformity for the LVD (2014/35/EU) when harmonized under that directive. Check the Official Journal of the EU for the most current list.
A: IEC 10026-6-00 can be used as a presumption of conformity for the LVD (2014/35/EU) when harmonized under that directive. Check the Official Journal of the EU for the most current list.