Learn about DIN rail mounted power supplies for industrial applications in this RS Ask the Expert Q&A with MEAN WELL Project Manager Kai Li.
For this edition of RS’s Ask the Expert series, we spoke with MEAN WELL Project Manager Kai Li about DIN rail mounted power supplies.
Hi Kai. Please tell us why you’ve chosen to talk about DIN rail mounted power supplies today.
DIN rail mounted power supplies are used in a wide variety of commercial and industrial applications and are key to ensuring the safe, flexible, reliable and economical operation of connected equipment, and MEAN WELL is a leading global manufacturer of standard power supply (SPS) products including DIN rail mounted power supplies. In fact, according to a 2021 Micro Technology report, MEAN WELL is the world’s #4 DC-output power supply manufacturer. MEAN WELL has designed and developed more than 10,000 standard power supply products and accessories for the SPS market and is a trusted partner in the power supply industry.
What are the primary selection parameters for DIN rail mounted power supplies?
As with all power supplies, the application dictates the parameters of the power supply. The wattage of the supplied load dictates the current capability for the AC service feeding the AC/DC power supply. MEAN WELL’s power supplies can accommodate common 120 V, 240 V and 480 VAC sources and provide 5 V, 12 V, 24 V and 48 VDC output voltages and are rated for ambient temperature range spanning -20°C to +70°C.
The highest-power DIN rail mounted power supplies we offer are the 960W WDR-960 Series and TDR-960 Series. The WDR-960 is available in single- and two-phase variants rated for 180–550VAC, while the TDR-960 is a three-phase unit rated for 340–550V and 340–550 VAC input, and both are convection cooled.
What do you mean by convection cooled?
Heat is the enemy of all electronic equipment. But unlike many competing solutions, MEAN WELL power supply products do not utilize fans, which, in addition to providing some cooling, decrease overall efficiency, increase maintenance requirements, draw dust into power supplies and introduce another potential point of failure into the system. Instead, MEAN WELL’s DIN rail mounted power supply products have a unique convection cooling design that leverages the natural movement of air within the enclosure.
MEAN WELL DIN rail mounted power supplies are used in sensitive industrial circuits that cannot tolerate power interruptions. How do they handle this issue?
MEAN WELL DIN rail mounted power supplies are used in sensitive industrial circuits that cannot tolerate power interruptions. How do they handle this issue?
MEAN WELL’s DBUF20 and DBUF40 Series DIN rail mounted buffer modules can be used to provide short-term backup for the load when the AC source power is temporarily interrupted, removing the need for an external battery that requires periodic testing and replacement to ensure efficacy in a time of need. The DBUF20 can sustain a 20 A load for 350 milliseconds at 24 VDC, while the DBUF40 can sustain a 40 A load for 250 milliseconds at 24 VDC.
What if the AC power interruption is longer than about one minute?
MEAN WELL also makes uninterruptible power supplies. These battery-based solutions, like the DIN rail mounted DR-UPS40 uninterrupted power supply (UPS) module, can provide backup power for extended interruptions, but they require regular battery testing and replacement, which can increase maintenance costs.
The DR-UPS40 UPS is intended for 24 VDC power systems, rated for a maximum of 40 A, cooled by convection air and equipped with LED indicators, a battery polarity protection feature and a battery test function that allows users to check the condition of the external batteries. The amount of time that it can supply a 40 A load depends on its battery size, so system designers should identify the desired backup period and select a battery capacity sure to maintain the load for that time. Backup periods are typically based on the amount of time required to allow system operators to either shut systems down in an orderly fashion or manually switch to an alternate AC source.
Some industrial applications can’t tolerate any loss of power. Does MEAN WELL have a solution to that problem?
Yes. Redundancy modules can be mounted on the same DIN rail as the power supply in industrial applications that can’t tolerate any loss of power. When the equipment’s preferred power supply is lost, the redundancy module instantly disconnects the faulty power supply and connects an identical unit to replace it.
How does MEAN WELL ensure the quality of its DIN rail-mounted power supplies?
MEAN WELL views quality manufacturing and product processing as a priority. We have maintained ISO9001 certification since 1994, ISO14000 compliance for environmental management since 2013 and OHSAS18001 compliance for employee health and safety since 2015. We also implement an audited total quality management (TQM) system. In addition, MEAN WELL DIN rail power supply products comply with various UL, cUL, TUV, CB, CE, GL and SEMI certificates for international suitability.
Additional Information
MEAN WELL is a trusted global supplier of standard power supply products used in various applications including but not limited to industrial market applications. For more information about the MEAN WELL products available through RS, please visit the embedded links above or click here to watch MEAN WELL product and application videos. For assistance identifying and deploying power supply products optimized for your unique application, please contact your local RS representative at 1.866.433.5722 or reach out to the technical support team.
