Design Of Electrical Safety Analyzer About Medical Equipment

With the continuous development of the technology, the medical equipment has been widely used in clinical diagnosis and treatment, thus, the patients and the operators would contact medical equipment directly or indirectly, so the operators misuse them or the facilities leak current, then the electric shock will occur.Therefore, How to use medical instruments safely deserves our great attention. In today's medical field, to evaluate a medical device need consider not only the effectiveness but also the safety of this equipment. The national standard, called as General Requirements for Safety of Medical Electrical Equipment Part released in July of 2008, makes strict rules for the electrical safety of medical devices, aiming to make sure the safety of medical devices during the use.After describing the development process and the related principles of the electrical safety testing of medical equipment, this paper discusses the testing device in detail, and according to the national standards, it studies the test method of the ground resistance, the insulation resistance and the leakage current of medical equipment in depth, then puts forward a multi-function electrical safety testing equipment for medical devices. so we can ensure that the medical device operates accurately and the testing equipment can evaluate the electrical safety features according to the test index.The tester applies embedded microprocessor to control its whole system, and it can standardized measure all the test indexes of the medical equipment electrical safety analyzer, being able to test the high-voltage, the leakage current and the ground impedance. The design of this system mainly consists of three parts: the programmable power supply design, the test and control circuit design. The test circuit applies the high-performance optical isolation amplifier to process the signal, and the leakage current measurement is based on the principle of the simulated human body network. The insulation test uses a relay network to realize automatic range switch. As for the ground resistance test, the sampling circuit consists of a constant current source and an analog-to-digital converter with magnification and filtering functions to simplify the normal testing. This design can be expected to achieve the automation of the testing process, and own safety monitoring of a number of indicators, high reliability and high test accuracy.