As many of you may already know, the tracking phenomenon in AC/DC Power Adapter occurs when moisture or dust accumulates around the plug inserted into an outlet, causing current to flow between the plug blades. Repeated spark discharges carbonize the surface of the insulating resin, forming a carbonized conductive path (track), which can ultimately lead to ignition.

Generally, as shown in the following diagram, a common countermeasure against this tracking phenomenon is to insert an insulating cap at the base of the plug and increase the base thickness to prevent short circuits.

Because this countermeasure is so well known, we occasionally receive questions from customers such as, "Are your AC/DC Power Adapter protected against tracking?"

In our company, there have been cases in the past where insulating caps caused issues during safety certification tests such as UL. Therefore, for wall-mount type AC/DC Power Adapter, we have long adopted a method of preventing tracking by providing a groove between the two AC plug blades.

This method is equivalent in performance to the insulating cap type. Naturally, it complies with PSE as well as UL and BSMI, which have similar plug standards, so you can use our products with confidence.