Testing Power Supplies for Medical Electronics Applications
The international standard IEC 60601 specifies testing performance for electrical devices used in medical applications. This standard has undergone some significant changes in the last number of years, with the recent adoption of the 3rd edition of the standard in 2012. In fact, IEC recently announced planned introduction of the 4th edition of the IEC60601 standard, slated for adoption in 2018, making it a design consideration for the next generation of medical equipment designs. Since the power supply is considered a component of a medical device, it is the applied part – meaning the medical electronics
end-product – that must be evaluated for overall performance to meet standard’s requirements. Although a power supply cannot be “certified,” it can be designed and tested to meet the necessary levels of performance according to the applied parts’ intended applications. Testing power supplies to this medical standard can help manufacturers optimize their medical designs to achieve the highest performance and safety levels and thereby enable first-pass success during agency approvals. This paper describes how Excelsys Technologies Xsolo power supplies have been designed and tested to meet both the B and BF type requirements per the IEC 60601 standard.
Safety Classifications for Medical Applied Parts
In July 2014, the IEC updated the medical standard IEC 60601-1-2 as related to “Medical electrical equipment – Part 1-2: General requirements for basic safety and essential performance – Collateral Standard: Electromagnetic disturbances – Requirements and tests.”
The 60601 standard cites three classifications for meeting these requirements: CF, BF, and B. The requirements for leakage current for these classifications are shown in Tables 1 and 2 on page 2, which are taken from the IEC 60601 specifications.The CF, or Cardiac Floating, is the most demanding performance level. Applied parts falling under this rating have application in products including, but not limited to, ventricular assist devices (VADs) or dialysis machines.