Engineers must ensure safety and reliability when designing low-voltage switchgear and controlgear assemblies. Excessive heat is a primary cause of component failure and electrical fires. The International Electrotechnical Commission (IEC) published to address this risk.
The method was developed based on empirical test data and, when applied correctly within its scope, provides results that are generally accurate enough for design verification purposes. For critical applications, testing may still be advisable. iec tr 60890 pdf