How to Read and Understand Labels of AC/DC Power Adapters — Desktop & Wall-Mount

This page clearly explains how to read and understand the information printed on the label side as described in AC/DC Power Adapters — Desktop & Wall-Mount.

How to Read Labels on AC/DC Power Adapters — Desktop & Wall-Mount

Labels on AC/DC Power Adapters — Desktop & Wall-Mount contain various types of information. There are many types of electrical devices in the world, and accordingly, there are various specifications for AC/DC Power Adapters — Desktop & Wall-Mount. Consequently, the label formats also vary according to these specifications.

Model Name, Input, Frequency

  • "Model No"
    Refers to the model name or type. "I/P" below it stands for "Input".
  • "I/P AC100~240V"
    Indicates that the input voltage supports AC100V~240V. In Japan, typical household or office outlets provide 100V. Overseas, electricity is typically supplied in the range of 110V~130V or 220V~240V, so adapters with "AC100V~240V" can be used globally, including in Japan.
  • "50/60Hz"
    Indicates multiple frequency ratings. Japan roughly has two frequencies: 50Hz in eastern Japan and 60Hz in western Japan.
  • "0.4A"
    Indicates the maximum AC input current.

Output

  • "O/P"
    Means "Output".
  • "O/P:DC5.9V 2.0A"
    Indicates a rated output of DC5.9V 2.0A.
  • "11.8W"
    Represents the wattage.

LPS

  • "L.P.S"
    Stands for Limited Power Source. LPS refers to a power source that has limited maximum output voltage, current, or power. Defined under IEC60950.

Trash Can Mark

  • Trash Can Mark
    This icon with a crossed-out trash bin represents the WEEE directive announced in the EU around 2003. It encourages recycling rather than landfill disposal.

Safety Standard Marks

  • Safety Standard Marks
    Displays safety marks such as PSE, CE, and UL. For more detailed information, refer to the specific page on safety standards.

I.T.E. Power Supply

  • "I.T.E. POWER SUPPLY"
    Shown near the UL mark, this indicates a power supply designed for information technology equipment in accordance with IEC/EN60950. If it's compliant with IEC/EN62368 for audio, video, IT, or communication tech equipment, it will say "AUDIO/VIDEO AND I.T.E POWER SUPPLY". For IEC-60601 medical compliance, it will say "MEDICAL EQUIPMENT".

House Symbol

  • House Symbol
    This house silhouette icon indicates the device is for indoor use only. Some versions include an arrow overlapping the house symbol.

Double Insulation

  • Double Insulation
    This circular mark represents double insulation, which refers to both basic and supplementary (or reinforced) insulation measures. (IEC Safety Class II)

Plug Polarity

This symbol indicates the polarity of the DC plug. In this case, the outer diameter is negative and the inner diameter is positive — referred to as center-positive.

If it is center-negative, the following symbol is used:

Also, according to JEITA standards, types that correspond to EAIJ use a diamond shape; others use a circular shape.

Other Labels and Symbols

Some AC adapters may include additional symbols or markings. Here are a few examples:

DC Mark

Altitude Mark

Represents a power source not suitable for use above 2000m according to China GB standards. A 5000m version also exists.

DIN Mark

Indicates the pin assignment configuration of a DIN plug.

PC Recycling Mark

The PC recycling mark from the PC 3R Promotion Association of Japan.

Orange Mark

A China RoHS mark, with the number indicating the usage limit in years.

Stripe

Indicates unfinished processing on the cut end of the DC cable.

Type-C Pin Assignment

Indicates the pin assignment of a Type-C plug.

IEC60417-5947 Short-Circuit-Proof Safety Isolated Transformer

GB Standard

Warning for equipment intended for use in non-tropical conditions.

Click here for safety marks by country