EDR-120 120W Industrial DIN Rail Power Supply 12V 10A 24V 5A 48V 2.5A AC DC Switching Power Supply for PLC Control Cabinet
- Output Channels: 12V / 24V / 48V
- Conversion Eff.: Up to 88.5%
- Form Factor: TS-35/7.5 or 15
- Protection: Short / Overload / OVP
Export Product Portfolio
Engineered LED Drivers & Industrial Switching Power Supplies
Precision-regulated AC/DC converters, TS-35 DIN rail mounting supplies, and heavy-duty IP67 LED power solutions manufactured with strict compliance to CE, RoHS, and international safety protocols.
100W Industrial AC/DC Switching Power Supply Wide Voltage Input Single Outputs 60Hz 50Hz Frequency
- Input Voltage: 85–264VAC Universal
- Ripple & Noise: < 100mVp-p
- Cooling: Free Air Convection
- Compliance: CE / RoHS Certified
EDR-240-24 Industrial DIN Rail Power Supply 24V 10A 240W Single Output AC-DC Switching Converter Slim Design 95% Efficiency
- DC Output: 24V @ 10A (240W)
- Peak Efficiency: 95% Ultra-Low Loss
- Chassis Profile: Slim Metal Cabinet
- Burn-in Test: 100% Full Load Aged
MDR-20 20W DIN Rail Switching Power Supply 12V 1.67A 24V 1A AC DC Single Output for Industrial Automation
- Power Rating: 20W Low Standby
- DC Output: 12V 1.67A / 24V 1A
- No Load Drain: < 0.75W Idle
- Mounting: DIN TS-35 Clip-on
EDR-120 120W DIN Rail Power Supply 90-264VAC Universal Input 12V 10A 24V 5A 48V 2.5A Industrial Switching Power Supply
- Line Input: 90–264VAC / 127–370VDC
- Dielectric Withstand: 3.0KVAC I/P-O/P
- Operating Temp: -20°C to +60°C
- EMC Standard: EN55032 Class B
LDV-100 100W IP67 Waterproof LED Power Supply 12V 8.3A 24V 4.2A AC DC Switching Adapter for Outdoor Lighting
- Ingress Rating: IP67 Fully Potted
- Output Voltage: 12V 8.3A / 24V 4.2A
- Thermal Sink: Extruded Aluminum
- Application: Architectural / Signage
SCP-35 35W Mini UPS Power Supply 13.8V 2.6A / 27.6V 1.4A with Battery Charger AC to DC for CCTV Camera Router Diesel Heater
- Battery Float: 13.8V / 27.6V Auto
- UPS Function: Zero Transfer Drop
- Protection: Battery Polarity / UVLO
- Primary Role: Telecom & Security CCTV
SP-500-12 12V 40A 500W Switching Power Supply with Active PFC & Cooling Fan for LED Lighting & Industrial Automation
- Power Factor: PF > 0.98 Active
- Output Current: 12V DC @ 40 Amperes
- Thermal Mgt: Intelligent Speed Fan
- Application: High-Bay LED & Robotics
Technical White Paper
The Engineering Dynamics of Modern Switching Power Supply Architecture
An authoritative analysis of circuit topologies, active power factor correction (PFC), thermal dissipation dynamics, and harmonic compliance standards for global electrical importers.
In the contemporary landscape of international power electronics commerce, the distinction between a commercial trading entity and an authentic original equipment manufacturer (OEM) hinges upon deep topological competence. Switched-Mode Power Supplies (SMPS) operating in commercial LED lighting, industrial programmable logic controller (PLC) enclosures, and building automation hubs are subject to extreme line fluctuations, electromagnetic interference (EMI), and elevated thermal ambient loads. As China's premier manufacturer and exporter based in Yueqing, Wenzhou—the worldwide epicenter for low-voltage electrical apparatus—Yueqing Keldan Technology Co., Ltd. builds its complete product taxonomy upon validated electrical engineering fundamentals rather than cut-corner assembly.
Topological Comparison: Flyback, Forward, Half-Bridge, and LLC Resonant Converters
Selecting an optimal switching topology dictates the energy efficiency, physical profile, electromagnetic radiation envelope, and long-term mean time between failures (MTBF) of the power converter. For sub-100W enclosed and DIN-rail systems (such as the MDR-20 and lower-wattage enclosed units), quasi-resonant discontinuous flyback topologies deliver exceptional cost-to-performance metrics, utilizing minimal passive magnetic components while providing galvanic isolation compliant with IEC 62368-1 and EN 61347-2-13.
However, when procurement specifications escalate into high-power commercial horticultural arrays, architectural linear LED runs, and heavy-duty automation panels spanning 200W to 500W (embodied in our EDR-240 and SP-500-12 configurations), classic flyback converters exhibit excessive drain-to-source voltage spikes and secondary rectifying diode switching losses. Here, Keldan leverages Active PFC Boost stages coupled with Half-Bridge LLC Resonant Converters. By achieving Zero Voltage Switching (ZVS) across the primary MOSFET switches and Zero Current Switching (ZCS) across the secondary synchronous rectifiers, switching losses are virtually neutralized. This topology elevation is the direct technical foundation enabling our EDR-240 series to register peak operational efficiencies up to 95%, dramatically minimizing thermal waste inside unventilated IP67 luminaire casings or cramped TS-35 electrical distribution cabinets.
| Circuit Topology | Typical Power Band | Efficiency Benchmark | PFC Stage Implementation | Primary Target Application |
|---|---|---|---|---|
| Quasi-Resonant Flyback | 15W – 90W | 84% – 88.5% | Passive Valley Fill or Single-Stage | MDR-20 DIN Rail, CCTV Auxiliaries, Compact Smart Home Sensors |
| Two-Switch Forward | 100W – 250W | 88% – 91% | Continuous Conduction (CCM) Boost PFC | EDR-120 Series, LDV-100 Waterproof Outdoor LED Drivers |
| Half-Bridge LLC Resonant | 200W – 600W | 92% – 95.5% | Interleaved Critical Conduction / CCM PFC | EDR-240, SP-500 Industrial Enclosed, High-Mast Flood Lighting |
| Full-Bridge Phase Shifted | 600W – 3000W+ | 94% – 96.5% | Active Bridgeless Totem-Pole PFC | Centralized DC Microgrids, Telecommunication Plant Inverters |
Active Power Factor Correction (PFC) & Total Harmonic Distortion (THD)
Stringent global import tariffs and efficiency directives—specifically the European Ecodesign Directive (EU) 2019/2020 (ErP Lot 7), US Title 24, and Energy Star specifications—mandate stringent input power quality. In an uncorrected capacitive rectifier circuit, current is drawn only at the crest of the sinusoidal AC voltage wave, generating severe third-order and higher harmonic currents that distort the municipal electrical grid and cause neutral line overheating in large-scale commercial facilities.
Keldan's SP-500 series and advanced LED switching supplies incorporate an automated active power factor correction controller that reshapes the input current wave into precise phase with the mains voltage. This achieves a Power Factor (λ) greater than 0.98 at rated load, while driving Total Harmonic Distortion (THD) under 10% across the universal input envelope of 90VAC to 264VAC. This level of harmonic mitigation guarantees complete compliance with EN 61000-3-2 Class C standards for lighting equipment, safeguarding tier-one EPC contractors from administrative border rejections or facility-level EMI non-compliance penalties.
18+
Years Engineering Expertise
Dedicated to R&D and SMPS conversion
44
Verified Onsite Specialists
TÜV Rheinland audited workforce
100%
Full-Load Burn-in Tested
Eliminates early-life component failure
>95%
Peak Electrical Efficiency
Achieved through LLC resonant design
Strategic Sourcing Roadmap
Future Procurement Trends in Industrial & LED Power Conversion
Navigating the structural transition toward wide-bandgap semiconductors, decentralized DC building grids, bidirectional power architectures, and real-time telemetry integration.
Transition to Gallium Nitride (GaN) & Silicon Carbide (SiC)
Procurement teams are shifting away from traditional planar silicon MOSFETs. GaN switches allow switching frequencies above 250kHz with minimal gate charge losses, shrinking high-frequency planar transformer footprints by 40% while sustaining exceptional power density inside ultra-thin enclosure profiles.
Projected Market Penetration: 64% by 2028
Decentralized 48V DC Microgrid Architecture
Modern smart warehouses and smart buildings are progressively discarding multiple localized AC-to-DC steps in favor of centralized class-2 48V bus systems. Our EDR series with native 48V 2.5A outputs fulfills this rapid architectural shift, mitigating copper conductor losses while facilitating direct coupling with renewable battery storage banks.
Annual Sourcing Growth: +28.5% YoY
Digital Power & Telemetric IoT Integration
The era of "dumb" static power supplies is coming to an end. Tier-one procurement criteria now frequently specify DALI-2, PMBus, or Modbus protocol integration over RS-485. Engineers require active telemetry on junction temperatures, operational hours, input surge peaks, and dynamic capacitor degradation monitoring.
Compliance Prerequisite for Smart Lighting
Potting Resins: Transition from Polyurethane to High-Tc Silicones
Extreme climatic deployment (e.g., desert solar plants, maritime architectural lighting) demands IP67/IP68 potting compounds capable of withstanding UV degradation and thermal cycling between -40°C and +85°C. Sourcing engineers increasingly prioritize dual-component thermally conductive silicone potting over brittle epoxy.
Thermal Conductivity Target: > 1.2 W/m·K
Modular Multi-Channel Programmable Drivers
To combat inventory fragmentation, global distributors are turning toward universal hardware platforms with software-configurable current limits (AOC: Adjustable Output Current via NFC or resistor plug). A single physical SKU can now cover ratings from 350mA to 1050mA, streamlining distributor inventory overhead by up to 60%.
SKU Consolidation Ratio: 4:1 Replacement
Total Cost of Ownership (TCO) & Lifespan Warranty Parity
Price-per-watt purchasing models have been superseded by 5-to-10-year Total Cost of Ownership calculations. Buyers calculate maintenance replacement labor, particularly in high-bay industrial or municipal infrastructure installations. Specifying long-life Japanese electrolytic capacitors (e.g., Rubycon, Nichicon rated at 105°C/10,000h) is now standard practice.
Minimum Sourcing Standard: 50,000 hrs @ 50°C
The Keldan Advantage
Verified Chinese Manufacturing Infrastructure & Technical Competence
Located in Malujiao Village, Beibaixiang Town, Yueqing—our facility bridges specialized electrical engineering, rigorous TÜV Rheinland-audited processes, and transparent OEM/ODM execution.
Advantage 01
TÜV Rheinland Onsite Verification
Unlike domestic broker networks, Yueqing Keldan Technology Co., Ltd. operates an onsite-verified production facility. The independent TÜV Rheinland assessment covers our SMT surface-mount operations, manual welding bays, mechanical punch workshops, and multi-tier quality control systems.
Advantage 02
Full SMT, Reflow & AOI Infrastructure
Equipped with high-precision automated pick-and-place systems, multi-zone nitrogen reflow ovens, and Automated Optical Inspection (AOI) units. Every printed circuit assembly is systematically checked for solder voids, solder bridges, component tombstoning, and reversed polarity.
Advantage 03
100% Thermal Burn-in Stress Matrix
Zero power supplies ship based on theoretical simulations alone. Our dedicated aging laboratory subjects every single produced batch of EDR, MDR, LDV, and SP units to 100% full-load thermal burn-in under elevated ambient temperatures to weed out early infant mortality defects.
Advantage 04
Bespoke Engineering & Fast Prototyping
Backed by veteran power electronics engineers boasting 5+ years of direct SMPS topology experience, we design custom output voltages, current limit thresholds, bespoke terminal block configurations, tailored sheet metal casings, and private-label silk-screening within rapid turnaround windows.
Keldan's 8-Stage Zero-Defect Quality Assurance Workflow
High-performance power supply reliability is not inspected into the product at the loading dock—it is systematically built into each manufacturing step. We execute an uncompromising 8-stage quality protocol:
Stage 1: IQC Incoming Inspection
LCR testing of capacitors, MOSFET RDS(on) curve tracing, and ferrite core permeability sampling.
Stage 2: High-Speed SMT Placement
Automated high-precision mounting of precision surface components with monitored paste thickness.
Stage 3: Thermal Profile Reflow
Controlled ramp-soak-spike profiles preventing internal stress in delicate semiconductor dice.
Stage 4: Automated Optical Inspection (AOI)
Sub-micron optical recognition verifying solder meniscus geometry, solder shorts, and part orientation.
Stage 5: Precision Through-Hole & Wave
Selective soldering of power transformers, large electrolytic banks, and chassis ground lugs.
Stage 6: Analog Calibration & Debugging
Potentiometer voltage centering, current trip point calibration, and OVP latch threshold testing.
Stage 7: 100% Load Thermal Burn-In
Continuous dynamic ON/OFF load cycling at elevated ambient temperatures to purge infant mortality.
Stage 8: Final ATE & Hi-Pot Testing
3.0KVAC isolation dielectric test, earth leakage verification, and barcode-linked packaging trace.
Procurement FAQ
Frequently Asked Questions: Sourcing & Engineering Due Diligence
Direct, technically detailed answers to critical questions faced by hardware procurement managers, electrical contractors, and distribution network executives.
What is the difference between Constant Voltage (CV) and Constant Current (CC) power supplies?
Constant Voltage (CV) power supplies (such as the SP-500-12 or standard 24V DIN-rail models) deliver a stable output voltage across varying load currents up to their rated ceiling. They are designed for parallel LED systems with onboard linear resistors or integrated DC-DC drivers (e.g., standard 12V/24V LED strip lighting and industrial PLC instrumentation). Conversely, Constant Current (CC) drivers modulate output voltage dynamically to maintain an exact constant current, which is critical for direct connection to raw high-power LED emitter strings to prevent thermal runaway caused by negative diode temperature coefficients.
How do you verify operational MTBF and electrolytic capacitor service life?
Mean Time Between Failures (MTBF) is mathematically computed per MIL-HDBK-217F or Telcordia SR-332 standards, regularly exceeding 200,000 to 500,000 operational hours across Keldan series. However, practical operating life is predominantly governed by the Arrhenius Law applied to internal electrolytic capacitors: for every 10°C drop in internal capacitor core temperature below its thermal maximum (e.g., 105°C), lifespan doubles. By over-sizing ripple current ratings by 30% and optimizing internal heatsink placement relative to airflow, our designs provide a validated field life of 50,000+ hours at 50°C continuous ambient duty.
What inrush current suppression mechanisms are integrated into Keldan SMPS?
When AC line voltage is applied to an uncharged capacitor bank, initial inrush currents can spike beyond 60 Amperes, potentially tripping standard Type-B circuit breakers or welding relay contacts. Keldan's 100W+ models incorporate Negative Temperature Coefficient (NTC) thermistors to limit cold-start inrush. In our higher-wattage industrial platforms (such as the SP-500 series), an active bypass relay or thyristor circuit short-circuits the NTC thermistor once the DC bus capacitor is charged, reducing continuous resistive power losses while resetting inrush protection for instantaneous subsequent cycles.
How is electrical isolation and dielectric withstand (Hi-Pot) verified?
Every manufactured unit undergoes automated end-of-line dielectric testing. For standard industrial reinforcement isolation (IEC 62368-1 / UL 1310 standards), testing requires Primary to Secondary (Input-to-Output) withstand of 3,000VAC (4,242VDC) for 60 seconds with leakage current strictly limited to < 5mA. Additionally, Primary to Frame Ground (I/P-FG) is tested at 1,500VAC, and Secondary to Frame Ground (O/P-FG) at 500VAC. We supply full isolation test certs and batch traceability with each commercial export consignment.
What are the differences between IP65, IP67, and IP68 LED switching power supplies?
Ingress Protection (IP) ratings describe barrier integrity against solids and liquids. IP65 specifies dust-tight protection against low-pressure water jets from any direction—adequate for sheltered industrial fixtures. IP67 (featured in our LDV-100 series) guarantees protection against dust ingress and temporary liquid immersion up to 1 meter depth for 30 minutes, achieved via vacuum-injected, bubble-free thermal silicone potting. IP68 represents continuous submersion under customer-stipulated hydrostatic pressures, requiring specialized cable glandular entries and hermetic enclosure designs.
What are the typical MOQ constraints and lead times for OEM/ODM private-label production?
For standard catalog items across our DIN-rail (EDR, MDR), enclosed (S, LRS), and LED adapter product lines, our base Minimum Order Quantity starts from as low as 1 piece for evaluation sampling, and 10 to 50 pieces for regular pallet orders. For custom OEM/ODM projects involving dedicated PCB layout adjustments, unique voltage-current trims, custom aluminum extrusion profiles, or private-brand silk-screening and localized packaging, baseline MOQs typically range from 200 to 500 units with initial engineering validation sample lead times of 7 to 15 working days.
