Overvoltage Category of Power Supply Products

As the international standard IEC 60664-1 define, the overvoltage category is also referred to as the installation category. The operating environment for powered electrical equipment is divided into four overvoltage category (OVC) areas according to their surge protection level. Four installation category areas from the least stringent to the most stringent are separated into OVC I to OVC IV. Here below states the difference between these four areas.

1. OVC I. Equipment of Overvoltage Category I (OVC I) is equipment for connection to circuits in which measures are taken to limit transient overvoltage to an appropriately low level. The typical application is equipment containing protected electronic circuits.

2. OVC II. Equipment of Overvoltage Category II (OVC II) is energy-consuming equipment to be supplied from the fixed installation. The typical application of such equipment are appliances, portable tools and other household similar loads.

3. OVC III. Equipment of Overvoltage Category III (OVC III) is equipment in fixed installations and for cases where the reliability and the availability of the equipment are subject to special requirements. The typical application of such equipment is switched in the fixed installation and equipment for industrial use with a permanent connection to the fixed installation.

4. OVC IV. Equipment of Overvoltage Category IV (OVC IV) is equipment connected at the origin of the installation. The typical application of such equipment is electricity meters and primary overcurrent protection equipment. High transient voltages are very likely to occur.


Overvoltage protection of high input voltage AC power supply

Overvoltage protection (OVP) is a critical feature of the power supply. It shuts down the supply when the voltages temporarily surpass the threshold value of the mains voltage or the preset level, which aims to protect the sensitive electronic components in the circuits of the connected devices from being destroyed by load dump, surges or transients from high voltage. MORSNUN AC/DC converters are designed with an over-voltage protection circuit to prevent such damage to the electronic components. These power products can reduce the occurring voltage peaks to a level that is not dangerous for the terminal devices. For example, MORSNUN LD-R2 Series OVC III AC/DC converters are ideal for OVC III applications and able to handle the over-voltage conditions easily so to ensure your power system works reliably and stably.

Advantages of MORNSUN LD-R2 Series OVC III AC/DC converter

Smaller, cost-effective, and reliable. MORNSUN AC/DC converter LDxx-23BxxR2 series rated from 3W to 90W are available for OVC III applications with reinforced isolation as high as 4.2kVac. They offer compact size with dimensions as low as 1 x 1 inch, ideal for various applications with limited space. Adopting such an AC/DC converter can help eliminate the isolation transformer, saving both cost and space.

This series has a universal wide input voltage of 85-305VAC or 100-430VDC coupled with a wide operating temperature range of -40~+85℃ and efficiency of up to 93%, which makes them suited for a wide range of commercial and industrial applications. Certified to IEC/EN/UL62368, EN60335 and EN61558, with 2-Y-capacitor design, EMI meeting class B without external components and no-load power consumption as low as 0.1W, the LD-R2 series is also perfectly fit for household appliances.

Delivering 3.3-48V DC outputs, the LD-R2 series is also ideal for equipment in a harsh industrial OVC III environment such as industrial control, EV charging station, IoT applications.

  • Universal Input Voltage

  • Industrial Temperature

  • Safety Certifications

  • 2-Y-capacitors design
    EMI class B without external
    components requirement

Power Solution for Access Control System

The power supply of the access control system is 12V. The entire system has card readers, alarms, door magnets, relays, etc., which are all powered by 12V. In the control circuit, the voltage is reduced to 5V and 3.3V through the Buck circuit to the MCU controller. Common 485 communication and Ethernet are used to power the communication part

MORNSUN - AC/DC Power Supply Manufacturer

Technical team. Our R&D engineers at MORNSUN have designed varied AC/DC power supplies catering to the various needs of your power systems. You can choose one or more of our advanced and cost-efficient components, from board mount AC/DC converters and enclosed switching power supplies to DIN Rail power supplies. 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!

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