Electrical Safety Testing

In order to verify the safety and functionality of medical device, manufacturers are required to perform electrical safety testing on their product according electrical safety standards.

STEMart provides comprehensive electrical safety testing to help manufacturers evaluate the potential risks of electrical shocks to customers when using their medical devices.

Standards

• IEC 60601-1 (International Electrotechnical Commission)
• IEC 62353 (International Electrotechnical Commission)
• NFPA 99 (National Fire Protection Association)
• ANSI/AAMI ES 60601-1 (Association for the Advancement of Medical Instrumentation)
• UL 60601-1 (Underwriters Laboratories)
• CAN/CSA C22.2 NO. 60601-1-08 (Canadian Standards Association)

Electrical Safety Testing

• Earth continuity test

STEMart provides Class ǀ equipment with earth continuity test to verify if there is a clear path between all exposed metal surfaces and the power system ground.

• Insulation resistance measurement

STEMart provides Class ǀ and Class ǁ equipment with various insulation resistance tests, including:

• Insulation resistance between mains parts and ground or the enclosure
• Insulation resistance between applied parts and ground or the enclosure
• Insulation resistance between applied parts and mains parts
• Equipment leakage current measurement

STEMart provides measurement of earth leakage current flowing between the power supply to the ground, which is applicable to Class ǀ and Class ǁ type B, BF and CF equipment.

• Earth leakage current measurement

STEMart provides measurement of leakage current flowing from the protective earth through the patient back to the protective earth conductor of the power cord, which is applicable to Class ǀ equipment.

Fig. 1 Earth leakage current measurement (Eisner, 2004)

• Touch current measurement

STEMart provides measurements of touch current flowing from any exposed conductive part of the enclosure to earth through the measuring device, which is applicable to Class ǀ and Class ǁ equipment.

Fig. 2 Touch current measurement (Eisner, 2004)

• Patient leakage current measurement

STEMart provides various patient leakage current measurements for Class ǀ and Class ǁ type B, BF and CF equipment.

Fig. 3 Patient leakage current measurement (Eisner, 2004)

• For Class ǀ and Class ǁ type B equipment, measuring the leakage current between all applied parts tied together and true earth;
• For Class ǀ and Class ǁ type BF equipment, measuring the leakage current between all applied parts with the same function tied together and true earth;
• For Class ǀ and Class ǁ type CF equipment, measuring the leakage current between each applied part and true earth individually.
• Patient auxiliary current measurement

STEMart provides measurement of leakage current flowing from a single applied part through the patient to all other applied parts tied together.

Fig. 4 Patient auxiliary current measurement (Eisner, 2004)

• Mains voltage on applied parts

STEMart provides measurement of leakage current flowing from each applied part through a current-limiting resistor to protective earth while applying 110% of mains voltage.

Fig. 5 Mains voltage on applied parts (Eisner, 2004)

• Mains voltage on signal input (SIP) and signal output (SOP)

STEMart provides measurement of leakage current flowing from applied parts tied together to protective earth while applying 110% of mains voltage to all SIP and SOP parts.

Fig. 6 Mains voltage on SIP and SOP (Eisner, 2004)

Combining in-depth electrical safety knowledge with the state-of-the-art laboratories and facilities, SETMart provides one-stop electrical safety evaluation solution for your medical device. If you want to learn more detail about our electrical safety testing service, or would like to consult with the experts at STEMart, please feel free to contact us.

Reference

• Eisner, L., et al. "Leakage current standards simplified." Medical Device & Diagnostic Industry 7 32-37 (2004).