Design Considerations

Input Source Impedance

The impedance of the input source connecting to the DC/DC power modules will interact with the modules and affect the stability. A low ac-impedance input source is recommended. If the source inductance is more than a few μH, we advise adding a 10 to 100 μF electrolytic capacitor (ESR < 0.7 Ω at 100 kHz) mounted close to the input of the module to improve the stability.

Layout and EMC Considerations

Delta’s DC/DC power modules are designed to operate in a wide variety of systems and applications. For design assistance with EMC compliance and related PWB layout issues, please contact Delta’s technical support team. An external input filter module is available for easier EMC compliance design. Application notes to assist designers in addressing these issues are pending release.

Safety Considerations

The power module must be installed in compliance with the spacing and separation requirements of the end-user’s safety agency standard, i.e., UL60950, CAN/CSA-C22.2 No. 60950-00 and EN60950: 2000 and IEC60950-1999, if the system in which the power module is to be used must meet safety agency requirements.

Basic insulation based on 75 Vdc input is provided between the input and output of the module for the purpose of applying insulation requirements when the input to this DC-to-DC converter is identified as TNV-2 or SELV. An additional evaluation is needed if the source is other than TNV-2 or SELV.

When the input source is SELV circuit, the power module meets SELV (safety extra-low voltage) requirements. If the input source is a hazardous voltage which is greater than 60 Vdc and less than or equal to 75 Vdc, for the module’s output to meet SELV requirements, all of the following must be met:

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The input source must be insulated from the ac mains by reinforced or double insulation.

The input terminals of the module are not operator accessible.

If the metal baseplate is grounded, one Vi pin and one Vo pin shall also be grounded.

A SELV reliability test is conducted on the system where the module is used, in combination with the module, to ensure that under a single fault, hazardous voltage does not appear at the module’s output.

When installed into a Class II equipment (without grounding), spacing consideration should be given to the end-use installation, as the spacing between the module and mounting surface have not been evaluated.

The power module has extra-low voltage (ELV) outputs when all inputs are ELV.

This power module is not internally fused. To achieve optimum safety and system protection, an input line fuse is highly recommended. The safety agencies require a normal-blow fuse with 5A maximum rating to be installed in the ungrounded lead. A lower rated fuse can be used based on the maximum inrush transient energy and maximum input current.

Soldering and Cleaning Considerations

Post solder cleaning is usually the final board assembly process before the board or system undergoes electrical testing. Inadequate cleaning and/or drying may lower the reliability of a power module and severely affect the finished circuit board assembly test. Adequate cleaning and/or drying is especially important for un-encapsulated and/or open frame type power modules. For assistance on appropriate soldering and cleaning procedures, please contact Delta’s technical support team.

Series E48SR specifications

The Delta Electronics Series E48SR is a cutting-edge power supply unit designed to cater to the demanding requirements of modern electronic devices. Renowned for its compact form factor and high efficiency, the E48SR series is ideal for various industrial applications, including telecom, data communication, and industrial automation.

One of the standout features of the E48SR series is its wide input voltage range. This versatility allows the unit to operate seamlessly across different regions and power environments, accommodating everything from standard AC mains to challenging scenarios like high-voltage fluctuations. The E48SR series supports a nominal input range of 100 to 240 VAC, providing a greater degree of flexibility for global deployments.

The E48SR series is also distinguished by its high efficiency, often exceeding 90%. This not only translates to reduced energy consumption but also minimizes heat generation, enhancing the longevity and reliability of the power supply. The incorporation of advanced technologies such as active PFC (Power Factor Correction) helps in maximizing efficiency while ensuring compliance with stringent energy regulations.

Another noteworthy characteristic of the E48SR series is its robust protection features. It is equipped with overload, overvoltage, and short-circuit protections, ensuring that both the power supply and connected devices are safeguarded against potential damage. These features are crucial in industrial applications where power stability is paramount.

In terms of thermal performance, the E48SR series employs a fanless design that enhances its reliability and reduces noise levels. This makes it particularly suited for environments where silent operation is critical, such as in office or laboratory settings. The unit is also designed for easy integration, with a standard footprint that fits into various mounting configurations.

Additional features include adjustable output voltage and current limiting, allowing users to customize the power supply to meet specific application needs. The E48SR series also supports remote sensing capabilities, enabling precise voltage regulation at the load end, further enhancing its usability in demanding scenarios.

Delta Electronics has built the E48SR series with durability in mind, ensuring that it can withstand harsh operational environments. With a wide operating temperature range, this series is capable of functioning reliably in extreme conditions, making it an excellent choice for mission-critical applications.

In summary, the Delta Electronics Series E48SR combines efficient power performance, robust protection features, and reliable thermal management in a compact design, positioning it as a preferred choice for various industrial applications.