Introduction

Motor drives, white goods, appliances, and other equipment may become unsafe to operate if one of their components fail. These equipments are subject to the testing and qualification requirements of the International Electrotechnical Commission (IEC). Specifically, the IEC 60730-1 standard covers automatic electrical controls for household and similar use.

Although compliance to IEC 60730 is attained at a system level, understanding the correct criteria for choosing a microcontroller is important to achieve compliance. The use of electronic components such as microcontrollers (MCU) is addressed by Table H.1 in Annex H of IEC 60730 "Requirements for electronic controls". Annex H specifies acceptable diagnostic techniques and measures applicable to an MCU in order to support the safe function of equipment.

While IEC 60730 is primarily used in Europe, similar practices are followed in the United States leveraging UL 1998 “Safety Software in Programmable Components.” Table A2.1 in Appendix A, provides examples of acceptable measures for microelectonic hardware failure modes that are consistent with the requirements of IEC 60730 Table H.1. These requirements are derived from the IEC 61508 standard, “Functional safety of electrical/electronic/programmable electronic (E/E/PE) systems.”