Isolation Transformers for Medical Applications

Posted by Bill Dull | January 24, 2024 0 Comments


Managing power for hospital equipment and devices is critical for the continued care and well-being of patients. Essential equipment should be isolated from the power source to protect it from disruption or interference. Most hospitals require that diagnostic and therapeutic equipment used in any medical applications be fully isolated with medical-grade electrical components called isolation transformers. These components act as a barrier between the equipment and the power source to provide these key outcomes:

  • Protecting patients and operators from potential shock
  • Protecting the equipment from surges and damage that can cause breakage or faulty readings

Isolation transformers halt the flow of unwanted or dangerous levels of electricity with very low current leakage levels. Medical-grade components are regulated by IEC 60601-1 standards and must meet extremely high levels of reliability and performance. Learn more about how medical grade isolation transformers differ from standard options and why it's critical for manufacturers to always use properly rated isolation transformers. 

What It Means for an Isolation Transformer to Be Medical Grade

Medical grade isolation transformers are designed and built to comply with the strict technical standards of IEC 60601. These standards, established by the International Electrotechnical Commission in 1977, guide manufacturing processes so medical electrical equipment provides safer and more reliable performance. Hospitals and other medical environments need electrical components specifically built for these settings—not only do different systems need to be able to run reliably without interference from other electrical systems within a compact space, but patients and medical service providers need to be able to rely on the performance of electrical equipment at all times. Faulty performance can be dangerous to operators, and interruptions in performance can be fatal to patients. But electrical components designed to adhere to these standards drastically reduce the risk of those outcomes.

Some of the characteristics of medical-grade isolation transformers, alongside their compliance with IEC 60601 standards, are:

  • Extremely low levels of current leakage: Each transformer must operate below a very low threshold of the maximum current allowance.
  • The transformers must be designed with minimum creepage distance: This clearance mitigates the risk of electricity moving from one conductive component to another nearby component.
  • Low temperature increases: Losses can increase the temperature of electrical components and equipment, but medical-grade isolation transformers don't allow the temperature to increase beyond a certain allowable level.

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Isolation Transformers for Medical Applications

How Medical Grade Isolation Transformers Work

There are two key ways medical grade isolation transformers work to protect patients, operators, and equipment:

1. Safety Ground

This option uses a conventional approach. A sufficiently thick shield sits between the primary and security coils of a configuration. This prevents electricity from jumping from one coil to the other along an unprescribed pathway. However, in the event of failure, these configurations have a safety ground: a pre-established electrical path that reroutes the electricity safely to the ground or another surface.

2. Double/Reinforced Insulation

These configurations don't have a safety shield and safety ground. Instead, they rely on a much thicker set of reinforced insulator materials. Both layers of insulation must have sufficient thickness and be able to handle high voltages. If one layer breaks during use, then the second shield handles the load.

Electrical configurations might also use a Faraday shield, which reduces total leakage current to below 100 microamps, or internal low-impedance isolation transformers, which completely isolate downstream components from the input line.

Benefits of Medical-Grade Transformers

Ultimately, medical-grade transformers make medical and non-medical devices or equipment in medical settings safer and more reliable. Some of the specific benefits they provide are:

  • Versatility in all medical contexts: Medical grade isolation transformers aren't just for life-saving equipment and critical interventions. They can also be used in IT equipment, monitoring systems, video networks, and more.
  • Protection for sensitive equipment: Isolating transformers can be combined with similarly high-performance plugs and outlets to ensure all devices in a patient environment contribute to a safe and reliable space.
  • Convenience in tight spaces: Because the transformers minimize interferences and unwanted magnetic fields, they allow electrical configurations to be near monitors.
  • Compliance: The transformers' compliance with standards is a necessary prerequisite for other regulations and product standards.
  • Design possibilities: Medical-grade isolation transformers are small, lightweight, and reduce demands for safety testing in new prototypes.

Learn More About Medical-Grade Isolation Transformers

At Triad Magnetics, we specialize in medical-grade and high-performance electronics components. Visit our medical equipment page to learn more, or browse our Medical Capabilities Brochure. You can also speak to our engineering team directly or request a quote to start your order.