This is the "umbrella" standard. It contains all the general definitions, service conditions, construction requirements, performance characteristics, and verification methods that apply to any type of low-voltage assembly (up to 1,000 V AC or 1,500 V DC).
These two parts work together; an assembly cannot be certified to Part 1 alone because it is not a complete product standard. Gt-Engineering
The IEC 61439-1 and 2 standard framework ensures a standardized approach to low-voltage switchboard safety. By standardizing design validation and eliminating ambiguous type-testing classifications, it protects operators, property, and industrial assets. For electrical engineers, mastering these rules is non-negotiable for delivering modern, safe, and efficient power distribution infrastructure. iec 614391 and 2 pdf
Using strict mathematical formulas and safety margins (e.g., calculating temperature rise for smaller assemblies).
Before 2009, the old IEC 60439 series had a different philosophy. The 61439 series introduced a : This is the "umbrella" standard
is the foundation. It defines the common rules, definitions, and service conditions for all low-voltage switchgear assemblies.
But why are Parts 1 and 2 always grouped together? Simply put, you cannot fully understand or comply with Part 2 without Part 1. This article will dissect both standards, explain their symbiotic relationship, outline their technical requirements, and discuss the legal and practical realities of obtaining the official documents. Gt-Engineering The IEC 61439-1 and 2 standard framework
2. Key Definitions: Original Manufacturer vs. Assembly Manufacturer
IEC 61439-2 defines various "Forms of Separation" (Form 1, Form 2b, Form 3a, Form 4b, etc.). These configurations use internal barriers, partitions, and covers to separate busbars, functional units, and terminals from each other. Higher forms offer greater protection against contact with live parts and limit the spread of internal faults. 5. The Compliance Workflow: From Design to Commissioning
The assembly manufacturer issues a test report and attaches a nameplate featuring the manufacturer's name, serial number, rated currents, and the specific IEC standards applied. Summary of Critical Responsibilities Responsibility of Original Manufacturer Responsibility of Assembly Manufacturer Short-Circuit Proofing Validates busbar system limits via lab tests. Selects components matching the validated limits. Thermal Performance Provides heat dissipation data for enclosures. Performs thermal calculation based on actual layout. Final Inspection Supplies instruction manuals and guidelines. Conducts final routine testing on the specific build.