Methods of performing computer controlled EMI compliance tests

It is pointed out that companies and laboratories are increasingly switching over from the standard, manually controlled, EMI (electromagnetic interference) compliance test equipment to new automated systems. These new systems are useful because they can drastically reduce the time and effort to perform EMI tests. However, these systems require forethought and careful planning in their use. The authors detail some of the problems encountered in the use of automated systems, and recommendations for resolving these problems. It is noted that all the EMC testing software available to date tends to add all the required correction factors to the original data. This significantly increases the risk of providing the reviewer with bad data. It is therefore suggested that the correction factors be employed to modify the specification requirement and leave the original data untouched. It is concluded that this method retains all the benefits of the automated test equipment, reduces the risk of error, and allows for verification of the test process