What is the earth to supply interference?
A. Common mode interference can also be a problem, and most microprocessor-base equipment will require a supply with this earth to neutral noise factor limited to less than 0,25V peak. For this reason, you may be considering installing a clean line from the mains distribution panel, but this will not always guarantee the required level of protection. Some times this can introduce more problems than it solves! Line conditioning will be the correct solution, achieved by fitting an isolating transformer with the secondary neutral linked to earth. This procedure will eliminate the need for a dedicated clean line, since at the point of linking neutral to earth, the common mode interference is nil. In other words, the neutral conductor is referenced to the local earth, eliminating the common mode supply interference caused by neutral currents. Stabilizers with added suppression interference like this are often referred to as line conditioners or power conditioners.
