MDR-20 Series
MDR-20 20W DIN Rail Switching Power Supply 12V 1.67A 24V 1A AC DC Single Output for Industrial Automation
Ultra-Slim TS-35
Low No-Load <0.75W
Class I Div 2
18+
Years of SMPS Engineering
TÜV
Onsite Audited Factory Verification
100%
Burn-In & Optical AOI Testing
4.8/5.0
Global Verified Buyer Rating
Standard & Custom Topologies
High-Efficiency Industrial Mini & DIN Rail Power Supplies
Direct OEM manufacturing portfolio designed for PLC cabinets, edge computing, smart metering, robotic controls, and harsh industrial switching environments.
HDR-100 Series
HDR-100 100W DIN Rail Power Supply 85-264VAC Universal Input 12V 24V 48V Industrial Switching Power Supply
Step-Shape Plastic
Isolation Class II
Building Automation
LRS-150 Series
LEYU LRS-150-24 150W 24V 6.5A AC DC Switching Power Supply Single Output Low Profile for Industrial Control
1U Low Profile (30mm)
5G Vibration Proof
Over-Voltage Clamp
NDR-240 Series
NDR-240 240W DIN Rail Power Supply 90-264VAC Universal Input with Active PFC 24V 10A 48V 5A Industrial Switching Power Supply
Built-in Active PFC
Metal Enclosure
EN61000-6-2 Heavy
Industrial Bench Series
3000W High Power Lab Bench Power Supply 0-24V 0-48V 0-110V Variable AC DC Converter for Industrial Testing Aging
Microprocessor Control
Continuous Burn-in
0.01V/A Resolution
Surge-Resistant SMPS
100W Industrial Switching Power Supply 300VAC Surge Input 5s 12V 24V 48V AC DC Converter with Overload Protection
300VAC Surge 5 Sec
105°C Electrolytic Cap
Hiccup Recovery
Cabinet Pro PFC
240W Industrial DIN Rail Power Supply with Active PFC 24V 10A 48V 5A AC DC Converter for PLC Control Cabinet
PF > 0.98 @ 230VAC
DC OK Relay Contact
Over-Temp Derating
Universal AC-DC
100W Industrial AC/DC Switching Power Supply Wide Voltage Input Single Outputs 60Hz 50Hz Frequency
85-264VAC Full Range
Convection Cooling
Short Circuit Clamp
Verified Production Footprint
Onsite-Verified Manufacturing Infrastructure & Technical Capabilities
Operating from Yueqing, Wenzhou—the nucleus of China's electrical apparatus industry—Yueqing Keldan Technology Co., Ltd. integrates component engineering, automatic SMT, and comprehensive burn-in procedures under TÜV Rheinland certified processes.
TÜV Rheinland Audited Integrity
Our manufacturing footprint, corporate financial standing, and QA/QC workflows have passed extensive onsite verification by TÜV Rheinland. This transparent supplier traceability provides Tier-1 system integrators with certified supply chain stability without intermediary markup.
Custom OEM & ODM Engineering
Backed by in-house R&D engineers averaging over 5 years in power electronics, we tailor planar transformers, current limit curves (constant current vs. hiccup mode), terminal pitch, low-profile mechanical enclosures, and private-label firmware interfaces.
Rigorous 8-Stage Quality Gate
Every mini power supply undergoes Incoming Component Screening (IQC), automated high-speed SMT placement, dual-wave reflow soldering, AOI optical defect screening, manual safety debugging, 100% full-load thermal burn-in, and final HIPOT dielectric isolation checks.
1
IQC Material Vetting
105°C rated capacitors, low-RDS(on) MOSFETs, and ferrite cores tested prior to line feeding.
2
Precision SMT & AOI
High-precision pick-and-place paired with automated optical inspection to verify solder joints.
3
100% Full Load Burn-In
Elevated ambient chamber testing under dynamic load conditions to trigger early infant mortality.
4
HIPOT & EMC Verification
3000VAC primary-to-secondary isolation validation, ripple verification, and CE standard compliance.
Industry Intelligence
Future Sourcing Trends & Next-Gen Power Architecture
Industrial switching power supply procurement is shifting from commoditized catalog ordering to strategic co-engineering. As automation panels, edge computing nodes, and distributed renewable arrays compress available cubic space, power supplies must deliver unprecedented power densities while meeting strict grid and harmonic mandates.
1. Wide Bandgap Semiconductors (GaN & SiC)
Gallium Nitride (GaN) and Silicon Carbide (SiC) switches are redefining the form factor of industrial AC/DC converters. By operating at switching frequencies exceeding 200kHz to 500kHz without thermal runaway, OEM factories can downscale passive magnetics and inductors by up to 40%. The result is high-wattage DIN rail and encapsulated bricks capable of sustaining 94%+ electrical efficiency in ultra-compact form factors.
2. Digital Telemetry & PMBus Diagnostics
Static power delivery is rapidly evolving into dynamic edge monitoring. Enterprise procurement teams increasingly require integrated I2C, PMBus, or IO-Link telemetry. Real-time logging of electrolytic capacitor ESR degradation, dynamic thermal load levels, instantaneous peak currents, and operating run-time provides predictive maintenance triggers before a failure halts production lines.
3. Wide Input Tolerances & Grid Distortion Immunity
Distributed microgrids, onsite photovoltaic arrays, and regional power fluctuations demand robust front-end resilience. Modern OEM power supplies incorporate extended 85-305VAC input ranges with transient withstand ratings up to 300VAC for 5-second surges. Built-in Active Power Factor Correction (Active PFC, PF > 0.98) minimizes reactive grid loading and eliminates penalties under EN 61000-3-2 regulations.
| Architecture Feature | Legacy Open-Frame / Generic SMPS | Keldan OEM Industrial-Grade Standard | Next-Gen High Density Roadmap |
|---|---|---|---|
| Power Density | 5 - 8 W / cubic inch | 12 - 18 W / cubic inch (e.g., LRS low-profile) | 25 - 35 W / cubic inch (Integrated GaN Topology) |
| Active PFC (Harmonics) | Passive or None (PF 0.60 - 0.70) | Active PFC (PF > 0.95) across >100W Lines | Interleaved PFC with Active Rectification (PF > 0.99) |
| MTBF Expectancy | < 150,000 Hours (Standard Caps) | > 350,000 Hours (105°C Long-Life Electrolytics) | > 500,000 Hours (Polymer / Ceramic Solid Caps) |
| Surge & Transient Margin | Basic Varistor Protection (1kV / 2kV) | 300VAC Input Surge withstand (5s), 4kV Isolation | Automated OVP Crowbar + Software Fault Logging |
| Cooling Requirements | Forced Fan Air (High Failure Risk) | Pure Free-Air Convection (-20°C to +70°C) | Integrated Direct Thermal Conductive Substrates |
Technical FAQ
Industrial B2B Procurement & Engineering FAQ
Direct answers to the most critical technical, compliance, and logistics questions submitted by global automation engineers and sourcing directors.
What is the engineering advantage of Active PFC in industrial mini power supplies?
Active Power Factor Correction actively shapes the input current waveform to mirror the sinusoidal AC mains voltage. In industrial environments with multiple switching loads, non-PFC supplies cause high harmonic current distortion (THD), stressing phase conductors and tripping upstream breakers. Units such as our NDR-240 and DRP series achieve a PF > 0.95 to 0.98, ensuring strict compliance with EN 61000-3-2 while reducing thermal losses in distribution panels.
How do we select between Constant Current Limiting vs. Hiccup Mode Overload Protection?
The selection depends entirely on your connected load profile. Constant Current limiting allows the power supply to sustain high inrush surges (essential for inductive motors, capacitive banks, and DC actuators) by dropping voltage while keeping current steady. Hiccup mode completely shuts down the switching cycle upon sensing an overcurrent condition, cycling power every few hundred milliseconds. Hiccup protection is safer for sensitive PCB sub-assemblies and communications gear where sustained short circuits could melt wiring harnesses.
Can Yueqing Keldan manufacture customized DC output voltages and custom mounting tabs?
Yes. In addition to standard 5V, 12V, 24V, 36V, and 48V outputs, our engineering department regularly winds specialized secondary transformer bobbins for non-standard requirements (such as 15V, 28V, or dual isolated bi-polar rails). We also retool external stamped sheet metal or injected plastic enclosures, alter terminal pitch (screw vs. spring-cage), and engineer custom mounting flanges for direct chassis or multi-angle DIN rail deployments.
What thermal derating rules should buyers apply for sealed control cabinets?
In sealed enclosures (IP65/NEMA 4X) lacking forced air ventilation, internal ambient temperatures often escalate to 50°C - 60°C. Standard switching power supplies should be derated starting from 45°C or 50°C, typically shedding 2.5% rated power per degree Celsius above that threshold. We recommend specifying units with a nominal headroom of 25% to 30% above your maximum sustained load to guarantee long electrolytic capacitor lifespan and eliminate thermal trips.
What documentation is provided to support international regulatory compliance?
Every batch export is backed by CE Declaration of Conformity (DoC), EMC test reports verifying EN 55032 / EN 61000 standards, Low Voltage Directive (LVD) reports, and RoHS / REACH material safety declarations. Upon request, factory dielectric withstand test data (HIPOT) and burn-in chamber logs can be certified and stamped for production lot traceability.
Launch Your Custom OEM Power Project Directly With Factory Engineers
Share your target electrical specifications, enclosure envelopes, compliance requirements, or annual production volume. Our technical export team provides initial circuit schematics, thermal calculations, and quotation packages within 24 hours.
