Press Releases

Power supply product
Compact Convection-Cooled High-Efficiency Open Frame Type
AC-DC Power Supply "ZWS300BAF" with 300W Max. Rating

October 22, 2012

TDK Corporation (President: Takehiro Kamigama, Head Office: Nihonbashi, Chuo-ku, Tokyo) has developed a 300W model to expand its ZWS-BAF series of compact, lightweight, high-efficiency open frame type AC-DC power supplies. The new product is available in 24V, 36V, and 48V versions and will be marketed by TDK-Lambda Corporation (President: Yoshiaki Hirota, Head Office: Nihonbashi, Chuo-ku, Tokyo), starting from October 22.

■ Development background and concept

By adding a 300W model to the popular ZWS-BAF series of compact, high-efficiency open frame type power supplies, the lineup now ranges from low power to high power types, helping to reduce the environmental impact of customers' products.
The ZWS300BAF has a maximum power rating of 300W and employs fanless convection cooling. This design eliminates the need for fan replacement and reduces acoustic noise and vibrations, among other advantages.

■ Product positioning

The ZWS-BAF series of AC-DC power supplies was developed in 2010. The new 300W model adopts a fanless design and has an efficiency(*1) of 91%. It is about 54% smaller(*2) than the predecessor model and consumes only 0.5W or less in standby mode(*3). The power supply is therefore effective in helping to reduce the environmental impact of products in which it is used. Thanks to a wide operating temperature range, it can be used also in severe environments. With the addition of a 300W model to the ZWS-BAF series, the ZWS lineup now provides an extensive array of solutions, including the ZWS-B series with wide input range and ZWS-BP series with peak load support.

  • (*1) At 24 V output, 200V AC input (*2) Compared to ZWS300 model (*3) Model with remote control ON/OFF option

■ Main features

  • Convection-cooled (fanless) type rated for 300W max.
    No need for fan replacement (maintenance-free)
    Use of external fan enables higher derating factor
  • Small dimensions, light weight, high efficiency
    91% efficiency(*1), approx. 54% smaller size(*2) than predecessor model
  • Low standby power consumption of 0.5W or less(*3)
  • Wide ambient temperature range for operation (-10°C to +70°C)
  • (*1) At 24 V output, 200V AC input (*2) Compared to ZWS300 model (*3) Model with remote control ON/OFF option

■ Major applications

General industrial applications such as test and measurement equipments, office automation equipment, industrial/commercial automated machineries, etc.

Outline of ZWS300BAF

Series name ZWS-BAF Series (Open frame type AC-DC power supply)
  • Convection cooled (fanless) type rated for 300W max.
  • Integrated RF suppression function
  • High conversion efficiency of 91%(*1)
        Reduced energy losses contribute to power savings of equipment
  • Significant size reduction of 54%(*2)
  • Significant control OFF standby power reduction to 0.5W max.
  • Wide ambient temperature range for operation (-10°C to +70°C assured for all models)
  • Free-of-charge warranty period 5 years(*3)
  • (*1) At 24V output, 200 V AC input (*2) Compared to ZWS300 model (*3) Conditions apply

■ Main specifications

Model name: ZWS300BAF

Model lineup

Model ZWS300BAF
Input voltage 85–264V AC (120–373V DC)
Output voltage 24/36/48V DC
Efficiency 91% (24V output, 200V AC input, typ.)
Output power 300W
Cooling Natural air cooling
Ambient temperature range
for operation
-10°C to +70°C
(-10°C to +45°C with 100% load, +50°C with 88% load,
+60°C with 64% load, +70°C with 40% load)
Noise control rating EN55011/EN55022-B, FCC-B, VCCI-B compliant
Safety standard compliance UL, CSA, EN
Other 84 x 42 x 180
Free-of-charge warranty period 5 years (conditions apply)

Order start date: October 22, 2012
*For order start date outside of Japan, please contact our sales office near you.

External view of ZWS300BAF

Image appearance

About TDK Corporation

TDK Corporation is a leading electronics company based in Tokyo, Japan. It was established in 1935 to commercialize ferrite, a key material in electronic and magnetic products. TDK's portfolio includes electronic components, modules and systems which are marketed under the product brands TDK and EPCOS, power supplies, magnetic application products as well as energy devices, flash memory application devices, and others. TDK focuses on demanding markets in the areas of information and communication technology and consumer, automotive and industrial electronics. The company has a network of design and manufacturing locations and sales offices in Asia, Europe, and in North and South America. In fiscal 2012, TDK posted total sales of USD 9.9 billion and employed about 79,000 people worldwide.

About TDK-Lambda

TDK-Lambda, a member company of the TDK group, markets a wide range of high reliability power supplies on a worldwide basis as a leading company in the market of power supplies for industrial equipment. It has a global network of 5 R & D centers (Japan, China, Europe, USA and Asia) and offers a complete set of services from R & D and production through sales and maintenance to meet diversified customer needs. For more details, please pay a visit to

■ Glossary

  • Derating factor
    Derating refers to operating a component or equipment at less than its rated maximum power or output in order to increase reliability. In the case of power supplies, derating involves reducing the power output at higher ambient temperatures compared to the output at normal temperature.
    The derating factor is calculated by correlating the performance margin to the normal rated output. The use of an external fan will increase the derating factor.

Product Information

Product information on this web site is intended only for the Japanese market.

For other markets, please access the respective regional web site or contact your nearest sales office.

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