Desktop and Wall Plug Power Adapters Ranging from 3 to 300 W

CUI’s line of external ac-dc power supplies is available in a variety of wall plug and desktop adapter configurations. From our low power fixed blade and interchangeable blade wall plugs to our high power desktop adapters, we are here to meet your external power needs. We offer a range of customization options including adding your logo, choosing your case color, and modifying dc cable lengths and plug options. With a full suite of safety approvals and high efficiency, our external power supplies are designed to keep your products running at their peak performance and in compliance with efficiency regulations across the globe.

External Ac-Dc FAQ

1.  What determines the number of prongs on a wall mount power supply?

Most wall mounted external power supplies are designed with only 2 input conductors (line and neutral) so the power supply can be plugged in either direction in a wall or power strip socket. The dc output voltage of these supplies is floating relative to ground since ac safety ground is not present at the input.

2.  Why do some desktop power supplies have 2 conductors and some have 3?

A 2-conductor power cord contains conductors for line and neutral while a 3-conductor cord also contains a conductor for ac safety ground. The output of a power supply with a 2-conductor cord will be floating relative to ground since ground is not present in the power supply. By convention, the output of desktop power supplies with 3-conductor power cords connect the negative output voltage terminal to ground.

3.  Why are the dc output cables limited in length on external power supplies?

A longer dc output cable contributes to worse load regulation and worse power conversion efficiency. User applications often require a minimum load regulation value and international standards set minimum power conversion efficiency levels for external supplies. Sometimes a dc output cable with larger gauge conductors can be used to enable the use of a longer dc output power cable.