References / Safety standards
Coil heating is an electrical estimate, not a measured temperature
Regulatory standardThe report estimates a coil's average power dissipation from I squared R heating and sorts it into low, moderate, and high bands. It always says plainly that this is an electrical estimate, not a measured coil surface temperature.
Where it appears in the report: Estimated Coil Power Dissipation
The evidence
Power dissipation is one input to surface temperature. The real temperature also depends on the coil's area, mounting, and cooling, so an electrical estimate can't pass or fail a temperature limit. Surface-temperature safety comes from direct physical measurement under defined conditions, a separate procedure described for medical electrical equipment in the general-safety standard. The band edges themselves are our convention for this class of small coil.
Primary sources
- IEC 60601-1:2005+AMD1:2012+AMD2:2020 (Ed. 3.2), Clause 11: Protection against excessive temperatures and other hazards.