Most electronics equipment fail to operate properly when there is evidence of power noise and disturbances. As we all know, this phenomenon is called Power Quality Problem. Generally, the problem can be classified as two different types. Type I is power line disturbances and noise carried in through incoming power lines. Type II is disturbances and noise generated within various sections of power distribution systems which is downstream from incoming power lines. This paper addresses a problem with EKG machine at Northrop Grumman Baltimore, Maryland site medical department. It appeared as power quality problem first but many series of tests on power ruled out the problem is not power related. The machine continued to produce erroneous test results which was completely impossible for doctors to understand. Further testing indicated that the EKG machine's failure was caused by high frequency noise from data lines. The EKG machine is E350i Interpretive Electrocardiograph, manufactured by Burdick Inc. The Burdick E350i is a multi-channel interpretive electrocardiograph that employs a thermal array point head to produce high-definition ECG records in a choice of 3,4 or 6 channel formats.
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