Is Yueqing Keldan Technology a manufacturer or a trading company?

We are a custom manufacturer with an in-house export team. Our production site has been verified onsite by TÜV Rheinland, covering production lines, QA/QC and trading capability.

Which certifications do Keldan power supplies carry?

Our standard DIN rail and switching power supplies are CE-marked. Test reports for specific models can be supplied on request so you can check compliance with your target market before ordering.

What is the minimum order quantity?

Many standard DIN rail and enclosed models can be sampled from 1 piece. Some series, such as the LRS CCTV series and low-profile DIN rail models, start from 10 to 15 pieces. Custom OEM projects have project-specific MOQs.

Do you support OEM and ODM customization?

Yes. We offer design-based and sample-based customization, including output voltage and current, enclosure, terminals, cable, private label and packaging.

How is every power supply tested before shipment?

Units pass incoming material inspection, SMT placement with reflow soldering, AOI optical inspection, manual debugging, full-load aging (burn-in) testing and a final finished-product inspection.

Should I choose a pure sine wave or modified sine wave inverter?

Choose a pure sine wave inverter for inductive loads, compressors, pumps, audio and sensitive electronics. A modified sine wave inverter is a cost-effective option for resistive loads such as heaters, lamps and simple tools.

TÜV Rheinland Verified Factory · Direct OEM / ODM

CE Certified Metal Case Power Supply Factory & Suppliers

Precision-Engineered Enclosed Switching Power Supplies, Industrial DIN Rail Converters, and Heavy-Duty Drivers Designed for Global Automation, Machine Vision, and Energy Systems.

18+ Years SMPS Engineering

44 Verified Workshop Staff

100% Full-Load Burn-In Tested

4.8 / 5 Global Procurement Rating

Engineered Recommendations

Featured CE Certified Metal Case & DIN Rail Converters

Direct-from-factory AC-DC switching solutions built with high-grade aluminum/steel perforated enclosures, active PFC, and industrial electromagnetic immunity.

Heavy Automation

500W 24V 20A Switching Power Supply AC DC Converter Single Output 90-132VAC 180-264VAC Industrial Equipment

500W / 24V 20A Switchable Input CE Certified

Datasheet → Send an Inquiry

Compact DIN Rail

HDR-100 100W DIN Rail Power Supply 85-264VAC Universal Input 12V 24V 48V Industrial Switching Power Supply

TS-35 Mount 85-264VAC In Ultra Slim

Datasheet → Send an Inquiry

IP67 Waterproof

LDV-100 100W IP67 Waterproof LED Driver Power Supply 12V 8.3A 24V 4.2A AC to DC Adapter for Outdoor LED Strip Sign Lighting

IP67 Sealed 12V / 24V Out Outdoor Grade

Datasheet → Send an Inquiry

Active PFC Built-In

SP-500-12 12V 40A 500W Switching Power Supply with Active PFC & Cooling Fan for LED Lighting & Industrial Automation

PF > 0.98 Forced Fan Cooling Low Harmonic

Datasheet → Send an Inquiry

Surge Resilient

100W Industrial Switching Power Supply 300VAC Surge Input 5s 12V 24V 48V AC DC Converter with Overload Protection

300VAC Surge (5s) 105°C Long Life Caps Robust Enclosure

Datasheet → Send an Inquiry

Control Cabinet

LEYU EDR-240-24 DIN Rail Power Supply 24V 10A 240W AC DC Single Output Active PFC Industrial Automation

240W / 24V 10A DIN Rail Mount EN 61000-6-2

Datasheet → Send an Inquiry

Universal Input

NDR-240 240W DIN Rail Power Supply 90-264VAC Universal Input with Active PFC 24V 10A 48V 5A Industrial Switching Power Supply

90-264VAC Range 92% Efficiency Metal Chassis

Datasheet → Send an Inquiry

Architectural Grade

LDV-100 100W IP67 Waterproof LED Power Supply 12V 8.3A 24V 4.2A AC DC Switching Adapter for Outdoor Lighting

Extruded Aluminum Silicone Potted Over-Voltage Prot

Datasheet → Send an Inquiry

Industrial Procurement Intelligence: Strategic Selection of Metal Case Switching Power Supplies

In modern industrial infrastructure, factory automation, robotics, and LED architectural installations, power distribution reliability dictates overall operational uptime. Switching power supplies (SMPS) housed in metal enclosures represent the frontline protection against electrical faults, harmonic degradation, and thermal failure. Sourcing engineers and system integrators must look beyond nameplate voltage and amperage to assess internal component topologies, isolation ratings, and harmonic mitigation standards.

A true CE-certified metal case power supply complies not only with the Low Voltage Directive (LVD 2014/35/EU) via safety standards like EN 62368-1 or EN 61558, but crucially adheres to the Electromagnetic Compatibility Directive (EMC 2014/30/EU). The metal perforated enclosure is not merely mechanical protection; it functions as a Faraday cage preventing conducted and radiated electromagnetic interference (EMI) from disrupting microcontrollers, sensitive sensors, PLC backplanes, and communication buses.

Active Power Factor Correction

Modern electrical grids mandate power factor correction (PF > 0.95). Integrated active PFC circuits suppress phase angle displacement and eliminate 3rd/5th harmonics, satisfying EN 61000-3-2 Class C & D compliance.

Thermal Dissipation Dynamics

High-conductivity honeycomb perforated aluminum bodies leverage natural convection. Heavy-wattage units (350W–500W+) integrate ball-bearing DC fans governed by smart thermal sensors to preserve electrolytic capacitor lifetime.

Four-Fold Protection Logic

Every industrial unit incorporates autonomous recovery or latch-off modes across Over Voltage (OVP), Over Current (OCP / Hiccup mode), Short Circuit Protection (SCP), and Over Temperature (OTP) safeguards.

Future Sourcing & Technological Trends in Metal Enclosed Power Supplies

B2B procurement dynamics for industrial power hardware are shifting rapidly under the dual imperatives of industrial IoT integration and global decarbonization initiatives. Sourcing directors and chief electrical architects must navigate these emerging technological trends over the next 3 to 5 years:

1. Gallium Nitride (GaN) and Silicon Carbide (SiC) Topologies

The transition from silicon superjunction MOSFETs to wide-bandgap GaN/SiC semiconductors allows SMPS units to operate at significantly higher switching frequencies. This shrinks magnetic transformers and inductors, enabling up to 40% volume reduction in metal enclosures while achieving 94%+ ultra-high efficiency with drastically reduced heat waste.

2. Wide Input Tolerances for Unstable Grids

With localized renewable energy integration and global cross-border deployments, power units must tolerate voltage sags and swells. Modern industrial supplies are engineered to withstand sustained 300VAC input surges for up to 5 seconds and maintain peak performance across cold starts from -30°C to +70°C ambient temperatures.

3. Modular TS-35 DIN Rail Standardizations

Control cabinet builders increasingly prefer tool-free snap-on TS-35 DIN rail designs over traditional screw-mount chassis. Compact stepped profiles (HDR/NDR series) optimize valuable control panel real estate, while front-facing DC OK relay contacts and potentiometer trimmers streamline commissioning.

4. Supply Chain Auditability & Decoupled Manufacturing

Procurement teams demand audited transparency. Factory-direct sourcing from established industrial hubs like Yueqing, Zhejiang—certified through independent onsite inspections like TÜV Rheinland—ensures traceable raw material batches, verified automated SMT lines, and auditable burn-in logs.

Manufacturing Authority: Yueqing Keldan Technology Co., Ltd.

Strategically situated in Malujiao Village, Beibaixiang Town, Yueqing, Wenzhou—the world-renowned epicenter of China's electrical apparatus industry—Yueqing Keldan Technology Co., Ltd. integrates 18+ years of switching power supply, DIN rail unit, pure sine wave inverter, and PWM solar controller expertise. Backed by an onsite TÜV Rheinland custom manufacturing verification, we bridge the gap between heavy industrial engineering and competitive B2B scalability.

TÜV Rheinland Verified

Fully inspected factory facilities, precision production processes, comprehensive QA/QC regimes, and proven international trade legitimacy.

Zero-Risk Qualification

Full SMT & AOI Inspection

Automated high-speed pick-and-place lines, lead-free reflow ovens, and Automated Optical Inspection (AOI) to eliminate soldering defects.

Component Precision

100% Thermal Burn-In

Every single metal case power supply passes computerized full-load aging test racks under elevated temperatures to eliminate early-life failures.

Military-Grade Testing

Dedicated OEM / ODM Lab

Experienced electrical engineers ready to customize voltage rails, current limits, enclosure geometries, cable harnesses, and private labels.

Custom Topologies

Precision SMT Surface Mounting

Automated Optical Inspection (AOI)

Conveyor Assembly Lines

100% Full-Load Burn-In Racks

Procurement Guide

Frequently Asked Questions by Industrial Sourcing Teams

Clear technical answers addressing compliance, testing standards, custom parameters, and warranty protocols before placing initial production orders.

How does your factory substantiate CE certification and European regulatory compliance?

Our standard enclosed metal case power supplies and DIN rail series comply strictly with the European Union Low Voltage Directive (LVD 2014/35/EU) and Electromagnetic Compatibility Directive (EMC 2014/30/EU). Units conform to EN 62368-1 / EN 60950-1 safety requirements and EN 55032 Class B / EN 61000-4 immunity standards. Official Declaration of Conformity (DoC) certificates, accredited third-party lab test reports, and RoHS declarations are made available to B2B clients for import clearance and compliance verification.

What testing procedures are applied to ensure zero defect rates during mass production?

Every production batch follows an 8-gate quality control hierarchy: 1) IQC testing on active components (MOSFETs, diodes) and electrolytic capacitors (105°C rated); 2) High-speed SMT assembly with AOI automated optical scanning; 3) Controlled reflow soldering profiles; 4) Through-hole insertion with automated wave soldering; 5) Initial manual debugging and calibration of voltage trimmers; 6) 100% full-load burn-in aging test (2 to 4 hours under maximum rated load); 7) Post-aging electrical re-test (Hi-Pot isolation test 3000VAC primary-to-secondary); 8) Final visual and packaging audit prior to palletizing.

What is the standard Minimum Order Quantity (MOQ) and sample lead time?

To assist automation integrators and distributors with pilot qualification, standard catalog products (such as 100W, 240W, 350W, and 500W enclosed or DIN rail units) have an evaluation MOQ of 1 piece. Volume production orders typically start from 10 to 50 units depending on the model tier. Fully tailored OEM/ODM projects (custom output voltages, conformal coatings, or bespoke chassis stampings) have negotiated project-based minimums. Standard samples dispatch within 2-3 business days.

Can you provide custom output voltages and tailored metal housings?

Yes. Yueqing Keldan Technology operates an in-house engineering team with 5+ senior power engineers. We provide sample-based and schematic-based customization, including non-standard output voltages (such as 36V, 60V, or dual isolated DC outputs), custom current limiters, military/tropicalized conformal coating for humid environments, specialized terminal block connectors, laser-etched brand labels, and private-label packaging.

What are the critical criteria when deciding between DIN Rail and Enclosed Metal Case SMPS?

Choose DIN rail power supplies (NDR, EDR, HDR series) when designing standard industrial control cabinets where modules must snap directly onto TS-35 mounting rails next to PLCs, contactors, and relays, saving maintenance time. Choose perforated metal case enclosed supplies (such as SP, S, or LRS profiles) when mounting directly onto machine chassis, 3D printers, CNC frames, or enclosed LED sign boxes where space efficiency, maximum watts-per-dollar ratio, and multi-angle mounting flexibility are paramount.

Request Factory-Direct Pricing & Custom Engineering Support

Connect directly with Yueqing Keldan Technology's technical sales engineers. Receive comprehensive product datasheets, CE documentation, and a competitive volume quotation within 24 hours.

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