Development Trend and Challenges of AC/DC Power Supply
Designed for White Goods and Household Appliances
COVID-19 restricts the activities of people, and many work and play spaces are limited to indoor spaces, which makes household appliances with smart and
Internet functions become more popular, freeing people from tedious and repetitive daily activities. Under such a general trend, the performance requirements
of white goods become more stringent, not only need safety but also need smart and compact, cost-efficient. AC/DC power supply is the core part to ensure
the normal operation of white goods and plays a very important role in ensuring the stable and safe operation of internet-enabled home appliances. Related
requirements also challenge the AC/DC power supply of household appliances as follows:
1. Improve the reliability of the power supply systems to ensure safety.
2. Compact size to adapt to various sizes of household appliances, saving space.
3. Simply design and save the cost of the whole system.
4. Higher power density and higher working efficiency.
5. Faster response speed of the control loop to improve the stability of the power supply system of devices. etc.
Requirements of AC/DC Power Supply for White
Goods & Commercial Household Appliances
How to design a high-quality household appliance power supply? As known, the most important criteria of household appliance power supply are safety. The safety standard IEC60335 and IEC61558 of household appliances has strict requirements for AC/DC power supplies, such as touch leakage current, clearance and creeping distance, and structural requirements. In addition, EMC performance also should take account of that EN55014 has specific requirements for it.
1. Touch leakage current. Leakage current is current that flows in the protective earth conductor or chassis. When there is no ground connection or it is broken this leakage current may flow through the human body. So the leakage current of household appliance power supply products must be strictly limited in order to avoid electric shock accidents caused by human touch with power supply products. The standard GB4706.1-2005/IEC 60335-1:2004 (ED4.1) stipulates that the contact leakage current is limited to 0.25mA, 0.5mA, 0.75mA, 3.5mA, and the specific classification is divided according to the type of devices. Please refer to below table 1.
| Touch leakage current | Applicable equipment/situation | e.g |
|---|---|---|
| <0.25mA R.M.S | Class Ⅰ: For circuits or devices that is not connected to or disconnected from the protective earth |
|
| <0.50mA R.M.S | Class Ⅱ: For handheld devices that are not connected to protective grounding. If the leakage current is greater than 0.50mA, it may cause an electric shock accident. |
|
| <0.75mA R.M.S | Class Ⅲ: For the handheld devices which power supply is connected to the protective earth |
|
| <3.50mA R.M.S | Class Ⅳ: For mobile/portable devices (except handheld devices), stationary pluggable equipment type-A, other stationary devices, etc. |
|
2. Electrical safety. In the IEC61558-1 standard, there are requirements of clearance and creeping distance for power modules in household appliances.
3. Structural requirements. EN61558 requirements that at the position between input-output of the product, must use two pieces of Y Capacitor or do not use Y Capacitor (Y Capacitor: a capacitor that does not cause shock hazard when it fails).
4. Good EMC performance. The EMC performance of the power supply for households should satisfy EN55014-1 (EMI)/EN55014-2 (EMS) standards.
MORNSUN AC/DC Power Supply Meets the Requirements of
White Goods & Commercial Household Appliances
To simplify the design while meeting requirements for the AC/DC power modules of white goods, home appliances, and smart appliances, designers can use
pre-packaged modules. Mornsun launches various AC/DC power supplies, which comply with EN60335 and EN62368, providing a convenient, guarantee for
the power supply design of household devices and appliances, greatly reducing devices' development costs and time to market.
1. Most Mornsun products are designed to limit the contact leakage current below 0.5mA, and also are verified according to the test method of IEC60990 Fig 4
to simulate the way the electrical leakage current passes through the human body, the contact leakage current is less than 0.5mA. Satisfied with the leakage
current limitation requirement of Class Ⅱ to Ⅳ devices according to standard GB4706.1-2005/IEC 60335-1:2004 (ED4.1). The touch leakage current of the
LS-R3 series is even less than 0.25mA. Please refer to the above table 1 or contact us at fae801@mornsun.cn for more information about product selection.
2. In order to ensure electrical safety, the power supply for household appliances was designed with enough electrical gap and creeping distance to meet the
requirement of IEC61558-1. For example, the Mornsun LM75-20B05 design maintains an electrical clearance of 7mm and a creepage distance of 10mm and
passed high I/O isolation test voltage up to 4000VAC.
3. The double Y structure of Mornsun's power supply for household appliances, such as the LD-R2 series , meets the requirements of the EN61558 power supply
and will not cause the danger of electric shock when the system fails.
4. Mornsun power supplies for white goods can meet the EMI/EMS standard requirements of EN55014 and even reserve sufficient margins to meet EN55032
Class B.
5. Even more, the power supplies are equipped with short-circuit protection and overload protection to ensure the safe operation of electrical appliances. In
addition, the AC/DC converters use the material for cases that passed the UL94 test and connector that passed the IEC60695 glow wire test, which can avoid
the danger of direct and indirect flame burning.
Power Solutions for Typical White Goods and Household Appliances
MORNSUN has established a global reputation and is committed to providing high-quality products and solutions. We have a strong presence in more than 40 countries worldwide and continue to forge partnerships that help us better serve our customers.
Application Cases
MORNSUN AC/DC Power Supplies Brochure
MORNSUN - Your Professional Power Supply Manufacturer
Technical team. Our R&D engineers at MORNSUN have designed a series of solutions with your white goods and household appliances needs in mind.
You can also choose one or more of our advanced and cost-efficient components, from isolation DC/DC converters and enclosed switching power
supplies to RS485/CAN transceivers and more. Guided by the service principle of "trustworthy", MORNSUN offers the best products, fast and local
service, and efficient pre-sales and after-sales support for clients worldwide.
MORNSUN provides professional power supply services. Backed by a perfect management system that consists of advanced research technology,
a high-quality raw material platform, advanced equipment, excellent manufacturing process management, specialized screening sequence on reliability and
rich experience, each solution from MORNSUN is designed to improve the stability, safety, and reliability of your power system.
Contact us now to request a sample and a quotation!
