CNC (computer numerical control) has changed the face of the manufacturing industry by automating the motion of factory tools and machinery using pre-programmed software. It has changed the process of how components are manufactured where all the three-dimensional cutting jobs can be done with the help of a single set of prompts. CNC routers and CNC milling machines are two of the more popular types of CNC machinery that manufacturers can consider for their workshop or manufacturing facility.

To assist your decision on that matter, this article compares the characteristics, applications, and suitability of CNC routers vs milling machines. This comparison will serve as your comprehensive guide to understand the nuances of each tool, whether you are a hobbyist seeking to optimize your workshop or a business owner aiming to strengthen production capabilities.

What is a CNC Router?

Generally, a CNC router is a computer-controlled cutting machine that is primarily used for softer applications. It acts like a normal hand held router, but with the added advantage of being able to computer control it, which minimizes the possibilities of cutting errors by small percentages. These machines are powerful tools that can slice, engrave, carve, and shape different materials with great efficiency and precision.

Key Features

Common characteristics of CNC routers are:

● High-RPM Spindles: CNC routers don't simply run higher RPMs than milling machines, they run much faster feed rates as well, meaning less time will be spent cutting. With a high-speed operation, they're well suited for softer materials.

● Gantry Style: Most CNC routers fall under the gantry-style design, where the cutting head moves over a stationary workpiece. Having two vertical columns on each side with the cutting tool spanning a horizontal frame, this design is perfect for working on large sheets of material.

● Multi-Dimensional Axis: CNC routers usually can move in 3 to 6 axes. Standard 3-axis machines can cut up and down (Z-axis) as well as in the X and Y direction, while more advanced 4-axis and 5-axis models can cut rotationally, coming in from other angles to create more intricate designs.

● Larger Work Area: In general, CNC routers have a larger cutting space, making them very convenient for working with sheet materials as well as for large format objects.

● Material Compatibility: CNC routers are typically designed for softer materials like wood, plastics, foam, composites, and softer metals such as aluminum and magnesium.

What is a CNC Milling Machine?

CNC milling machines are heavy-duty, computer-operated cutting tools for machining harder materials with high precision. Unlike routers, which prioritize cost and speed, milling machines are designed for strength and rigidity and can handle heavier cutting operations with impressive precision.

Key Features

Features of a CNC milling machine:

● Rigidity: CNC mills are built with a heavy-duty, permanent frame that allows them to perform highly vertical and horizontal cutting. This inflexible construction enables them to process more resilient materials while ensuring the utmost precision.

● Low-Speed High-Torque Spindle: A CNC mill uses a spinning spindle like a router except that it only spins between 1,000 to 20,000 RPM compared to a router. These industrialist titanium cuts give them the ability to make shallower cuts in harder things, but without sacrificing accuracy

● Multiple Axes: Basic CNC mills work on 3 axes while more advanced models can have up to 12 axes of movement. Such a wide range of motion allows complex machining that is impossible with simpler equipment.

● Precision: CNC mills are only the same CNC machines that can be designed with precision and dimensional accuracy in mind, making design projects with tight tolerances and intricate designs perfect for doing.

● Material Compatibility: CNC milling machines can cut harder materials, they are perfect for cutting metals (steel, titanium, stainless), plastics, and composites. They could offer the services to cut these materials at a high speed all without losing precision and accuracy.

Key Differences Between CNC Router and Milling Machine

Design and Structure

CNC routers are generally built in lightweight, gantry configurations, with the cutting head moving over a stationary workpiece. This involves two vertical columns on either side of the cutting tool, which moves along a horizontal framework. It is less rigid than a milling machine and thus has considerably lower precision capabilities, however is much faster and has a much larger area of operation.

CNC milling machines are designed with a robust, cast iron or steel framework that ensures exceptional rigidity and stability when in operation. They have a fixed frame and a movable workpiece for vertical and horizontal cutting.

Material Compatibility

CNC routers are made to cut softer materials. They shine at cutting wood, plastics, foam, composites, and soft metals — aluminum and magnesium. They can also work quickly, which is ideal for processing these materials without excessive heat or damage.

Due to this fact, CNC milling machines are designed to work with much hard and inflexible materials. They are able to process steel, stainless steel, titanium, copper, and other solid metals that would harm or damage a CNC router. Different sorts of metals like aluminum and steel are too hard for regular routers to do a good job because they will go deep while CNC routers won't.

Precision and Accuracy

The CNC router has a relatively good precision that is sufficient for many applications (it is usually not comparable to a milling machine). They have a less rigid construction and higher operating speeds that result in increased vibration and a propensity for deflection during cutting operations.

They offer much higher precision and accuracy compared to CNC milling, which makes them great for complex geometries and intricate designs. Their inflexible construction minimizes vibration and tool deflection, making for extremely precise cuts within tight tolerances. CNC mills use more advanced control systems that allow the cutters to move very precisely over rigid structures.

Speed and Torque

CNC routers run at much higher RPM than milling machines (18,000–24,000+ RPM). During high-speed operations, feed rates are high and material removal is rapid within soft material. ​However, the rotary cutters of CNC routers provide less torque, making them less effective for deep cuts in hard materials.

While CNC milling machines turn at slower RPM than routers, they offer much greater levels of torque. This enables them to make deeper, more aggressive cuts in harder materials without stalling or damaging the cutting tools. Because CNC mills operate at lower speeds with high torque, they are more efficient at removing large quantities of material from tough workpieces.

Cutting Area and Z-Axis Depth

Since CNC routers have a larger cutting area than milling machines, so they are mostly used to process large sheets of material. The expanded work envelope enables both the manufacture of larger components and the concurrent production of multiple, smaller parts. That said, a CNC router does tend to have a shallower Z-axis travel depth meaning that although routers are great at processing standard material width quickly, the overall thickness of material they can adequately process is thinner with shallower depths and usually less appropriate for cuts with depth.

The smaller cutting area of CNC milling machines especially when compared to routers limits the workpieces that they can accommodate. They replace this limitation with a much larger travel capability in the Z-axis. These CNC mills can work with thicker materials and make deeper cuts, which is crucial for many metalworking applications.

Cost and Maintenance

CNC routers are usually cheaper and easier to maintain, but they do have residual dust and swarf that need regular cleaning, especially when used for cutting wood.

CNC milling machines require a considerable initial investment owing to their rugged design, sophisticated technology, and accuracy. They also have much higher operational costs, associated with costlier tooling, higher power requirements, and more frequent maintenance. CNC mills require more maintenance since they work with tougher materials and at higher stress levels.

Applications and Use Cases

CNC Router Applications

CNC routers can be found in a number of industries and offer a versatile and efficient method for shaping softer materials. Some common use cases include:

● Woodworking: CNC routers perform exceptionally well in woodworking applications, such as producing drawer fronts, drawers, shelves, countertops, and cabinet doors.

● Sign Making: CNC routers are heavily utilized in the sign industry to cut signs out of different materials like plastic, foam, wood, bronze, and aluminum. With 3D capabilities, sign makers can create signs with dimension and texture.

● Modeling and Prototyping: Working in plastics, wood, foam and aluminum to build models and prototypes for product development.

● Music Instruments Sector: Production of musical instrument parts with a high level of repeatability and high precision resulting in customized musical instruments with distinct requirements.

● Exhibition & Display: Collaborating for custom tradeshow & exhibition works using acrylic, vinyl, glass, and wood.

CNC Milling Machine Applications

Industries that require precision machining of tougher materials to exact tolerances rely heavily on CNC milling machines. Their applications include:

● Aerospace: Fabricating aeronautical parts out of materials such as titanium and aluminum, where high precision and light-weighting durability is important.

● Automotive: Parts such as cylinder heads, drive axles, suspension parts, exhaust parts, and gearboxes can all be made with the efficiency and precision the automotive industry requires.

● Medical Devices: Manufacturing precision parts for medical devices and implants where tight tolerances and biocompatible materials are essential.

● Electronics: Making precision housings, heat sinks, and other components for electronic devices.

● Mold Making: This includes the creation of complex molds for injection molding and other forming processes, wherein precision directly impacts the quality of the end products.

● General Manufacturing: Manufacturing of common components like gears, shafts, nuts, bolts, flanges, etc., used in a variety of industrial applications.

CNC Router Pros and Cons

Pros

Speed and Efficiency: For machining certain materials, CNC routers can be much faster than other technologies, enabling quick and efficient production times and higher throughput.

Lower Start-Up Cost: CNC router machines generally have a lower start-up cost than milling machines, making them more attainable for small businesses and hobbyists.

Flexible for Soft Feed Material: Great for cutting wood, plastics, foam, and mild metals like aluminum.

Continuous Operation: Once running, operates continuously for indefinite periods with minimal to no loss of accuracy or scalability at no extra cost.

Cons

● Limited Material Joules: Of lower torque and less rigid construction, making it less effective with harder materials (like steel or titanium).

● Less Precision: CNC mills are far superior for complex jobs that require accuracy and tight tolerances.

● Dust and Residue: They create a lot of dust and residue and will need to be effectively extracted.

CNC Milling Machines Pros and Cons

Pros

● High Precision: High accuracy and tight tolerance ability to manufacture complex components.

● Material Versatility: Machinable on a variety of materials, including but not limited to soft aluminum to hardened titanium and stainless steel.

● Sturdy build: The rigid design limits vibration and minimizes deflection, which gives developers superior surface finishes and dimensional accuracy.

● More Z Axis Depth: More significant material removal and allows thicker stock.

● Complexity in Geometry: Force vector path multi-axis capabilities make possible the production of complex 3D shapes and textures.

Cons

● Invest More Money: Much higher upfront costs than CNC routers.

● Operates Slower: In some applications, machining times would take longer due to lower RPM operation.

● Reduced Work Envelope: Generally, has a smaller workpiece limit than the larger bed size of CNC routers.

How to Choose Between a CNC Router and Milling Machine

Material Type

The materials you plan to work with should be a primary consideration in your decision.

● Choose a CNC router if you'll primarily be working with wood, plastics, foam, or soft metals like aluminum.

● Opt for a CNC mill if your projects involve harder metals like steel, stainless steel, or titanium, or if you need to machine materials with exceptional hardness.

Project Size and Scope

Consider the dimensions of your typical workpieces.

● A CNC router is preferable if you need a larger work surface for processing sheet materials or creating large-format items.

● A CNC mill might be better if your projects are smaller but require deeper cutting capabilities or more complex three-dimensional features.

Precision Requirements

Assess how critical dimensional accuracy is for your applications.

● If your projects can tolerate moderate tolerances and don't require extremely fine details in hard materials, a CNC router may be sufficient/

● If you need tight tolerances, superior surface finishes, or intricate features in tough materials, a CNC mill is the better choice.

Budget Constraints

Consider both initial investment and ongoing operational costs.

● CNC routers offer a lower entry point and generally less expensive operation, making them suitable for businesses with limited capital or those just starting out.

● CNC mills represent a larger investment but may provide better long-term value for applications requiring their specific capabilities.

Production Timeline

Think about your production speed requirements.

● CNC routers operate at higher speeds and can process softer materials more quickly, making them advantageous for higher-volume production of appropriate items.

● CNC mills work more slowly but can handle materials and operations that routers cannot, so the timeline must be balanced against capability requirements.

Conclusion

Hope this article helps you in your selection between CNC Router and Milling Machines based on your manufacturing requirements, material, precision, and budget. In this comparison, we have shown you the main differences between these two CNC technologies.

Have questions about CNC machines? Exploring the right option for your specific application is crucial, and consulting with industry professionals can provide valuable insights tailored to your unique requirements. Consider reaching out to manufacturers or visiting showrooms to see these machines in action before making your final decision.

The automated manufacturing tool known as Computer Numerical Control (CNC) operates through programmed code instructions to shape and cut materials including metal, wood, foam and plastic. The process of learning CNC equipment setup and operation requires both study and practice yet basic CNC mastery enables both hobbyists and professionals to create precise parts efficiently.

This guide provides step-by-step education for beginners who lack CNC experience through detailed explanations of standard CNC workflow preparation and programming and machining and maintenance procedures. The article provides essential information about CNC terminology and equipment components and safety protocols which every CNC operator must learn.

What is a CNC Machine?

CNC machines operate as automated milling and routing tools with drilling and cutting capabilities which use computerized controls to transform stock materials into custom parts and designs. The automation of manual machining operations through CNC systems delivers enhanced precision and speed together with repeatability and complex capabilities beyond what human craftsmen could achieve.

The main CNC machine categories consist of milling machines, lathes, routers, laser cutters and plasma cutters. Advanced 5-axis CNC machines have the capability to execute complex three-dimensional cutting operations. The majority of CNC machines used by hobbyists function as vertical milling machines with adjustable beds or small routers.

Common Types of CNC Machines

● CNC Mill - A versatile computer controlled vertical milling machine center, typically with a movable table or bed that the workpiece is secured to. Common configurations are 3-axis (X, Y, Z motion) and 5-axis (with rotary axes) controlled.

● CNC Router - A gantry style machine that moves a spindle over a stationary table and is ideal for routing wood or soft materials. Z-axis is controlled, allowing intricate 2D and 2.5D shapes.

● CNC Lathe - Highly rigid and accurate computerized turning center that rotates the part while the cutting tools move radially to cut complex patterns on the sides of the workpiece.

● CNC Plasma Cutter - Uses a digitally controlled plasma arc to melt and cut electrically conductive materials like stainless steel or aluminum. Tolerances down to 1mm.

● CNC Laser Cutter - A CO2 laser beam burns through sheet stock by either vector cutting outlines or rastering patterns. Ideal for precise, clean cuts in wood, acrylic, fabrics, and paper.

● CNC Waterjet - An extremely high pressure stream of water with abrasives cuts through metal, glass, foams, plastics, and composites along a programmed path with zero heat damage or fumes.

Key Components and Terminology

It's vital to understand the physical components and motion capabilities of a CNC machine before attempting operation:

● Axes - The moving directions labeled X, Y, Z that the tool or part can be positioned along using coordinated motion control.

● Spindle - The electric high speed motor that rotates the cutting tool or bit at RPMs sufficient for machining.

● Collet - The clamping chuck on the machine's spindle that grips and secures the cutting tools.

● Gantry - The bridge assembly that allows movement of spindles or material over the workspace below.

● Working Envelope - The maximum part size capacity based on the machine's travels along each axis.

● Controller - The computer and monitor that converts CAM-generated G-code into electrical signals that command axis stepper motors.

● Stepper Motors - Precise digital actuators that can position the axes or spindle speed based on input pulses.

Preparation Before Using a CNC Machine 

A CNC device requires proper setup before turning on the power for any cutting operation to proceed safely. The failure to properly set up the machine and workspace creates risks that range from equipment damage to serious injuries from flying debris and sparks and other potential hazards.

Safety Precautions and Gear

You should examine both the operational manual and risk assessments for the CNC model you operate because it contains unique hazards. General safety tips include:

● Protect your eyes with safety glasses and your ears with ear protection and wear shoes that cover your entire foot while operating equipment.

● Check for machine stability before adjusting the leveling feet when operating on an uneven floor surface.

● The work area must have open pathways for access and no slippery surfaces should exist.

● Long hair should be secured and all loose clothing and jewelry and other objects must be removed to prevent them from getting trapped in machine parts.

● Keep a first aid kit and fire extinguisher easily accessible in the work area.

● The machine operator needs to install methods that reduce risks according to the machine specifications and material cutting requirements.

Understanding the Blueprint or CAD Design

CNC machining requires a digital design file generated from CAD software which defines the desired part geometry. Common file types are .DXF files or CAM specific files with toolpath information. The operator must fully understand the critical dimensions, geometries, any datum references or other specifics called out in the blueprints or models before attempting to replicate them physically.

Pay attention to fine details regarding necessary hole sizes, surface finishes, tolerances, or notes clarifying setup instructions or machining steps. Planning may be required for necessary fixture creation or workholding choices as well.

Choosing the Right Material and Tools

The raw material blanks must match the type and dimensions specified in the cutting plan. Ensure adequate stock is available for the entire job or production run with consideration for potential scrap and defects needing discarded. Stable sheet goods should be flattened if warped to allow proper holding.

Selecting suitable cutting tools is also mandatory for efficient material removal without tool failure or damage risk. Consider factors like these when tooling up:

● Flute count, helix angle, length, diameter based on optimum chip loads

● Tool coating durability for the specific material hardness and run durations

● Insert shape and angle tuned for effective shearing action

● Tool stick out constraints to minimize vibration and deflection

Sharp and undamaged tooling is essential for clean, accurate cuts and optimized machine performance.

Step-by-Step Guide to Operating a CNC Machine 

Once the necessary safety steps have been performed and the job has been programmed and tooled up for, the hands-on CNC operation can commence. The following procedural checklist summarizes the key usage steps that typical small-scale CNC workflows follow from power-on to finished parts.

Step 1: Setting Up the Machine

Locate the master electrical disconnect switch and set it to "ON" to energize the device. Then toggle the operational power button to initialize the control panel and operating system. Stepper motors will likely need to index their positions as part of this startup synchronization.

Per manufacturer guidance, certain critical machine components may require time to reach steady-state operating temperatures before cutting begins. Spindle bearings, ballscrews, and electronics need proper heat levels and lubricant viscosity to function accurately and reliably.

Step 2: Securing the Workpiece

Degrease and clean the table surface or subplate where workpieces will be mounted. Select appropriate vises, clamps, toe clamps or custom fixturing solutions to securely hold parts in place while managing chip and coolant runoff.

Improperly aligned parts risk tool strikes, dimensional errors, unwanted vibration and other technical issues. Confirm with indicators like dial test indicators that the workpiece is both immobile and precisely oriented relative to the machine zero position.

Step 3: Loading the CNC Program

.NC files contain numerical control instructions to direct machine movements and functions. Other extensions like CNC or TAP also store coded cutting data. CAM software converts 3D models to G-code toolpaths automatically.

Use USB drives, Ethernet networks or the controller interface to upload program files created offline into the CNC system's memory storage location. Verify the proper file name and storage path to avoid operational issues.

Step 4: Tool Setup and Calibration

Carefully insert cutting bits fully into the machine's collet or chuck, avoiding contact with the delicate flutes. Tighten to appropriate torque specifications with matched wrench sizes.

Input or digitize each tool's radial dimensions and tip length values to record into the tool library offset register. This allows compensation for differences during program run time.

Trial actual hole drilling, surfacing or profile cutting to dial-in and validate entries. Continually refine offset data until satisfied with tool behavior before starting final program.

Step 5: Setting Machine Zero

The CNC controller orients all commanded positioning, rapid moves and cutting passes to a defined coordinate system tied to the workpiece location and stock boundaries.

Instruct the machine to travel to touch off points helping correlate the vise or fixture coordinates to the workspace axis positions reported. This "zeroing process" syncs the programming perspective to actual tool tip placement.

Step 6: Dry Run and Simulation

Always simulation full G-code program execution at rapid speeds without engaging cutting. Seriously risk and liability reduction step to validate positioning, catch any crashes.

Many advanced CNC controllers include a realistic 3D graphical environment rendering the entire machining sequence. Use to help visualize program behavior.

Step 7: Executing the Machining Process

With a proven, vetted toolpath program now loaded, carefully begin the full production run. Monitor constantly for any alarm conditions or abnormalities requiring an immediate feed hold or full stop. No unattended operation.

Control feed rates, spindle speeds and other critical parameters must match both program settings and equipment capacities to achieve target finish quality and prevent tool breakage. A conservative approach is smart initial practice.

Step 8: Finishing the Process

Upon fully completing all encoded operations without any axis overtravel errors, the CNC machine will signal job done status. Inspect finished part inside the machine before removal.

Carefully remove workpiece from fixture or vise without damage after power disabled. Also clear tool debris and machining detritus from moving components near way covers to prevent accumulation.

Post-Processing and Quality Checks 

Deburring and Surface Finishing

Manually reviewed the machined workpiece for any remaining burrs, casting flash or undesirable surface inconsistencies needing improvement using bench grinding or sanding techniques. Edge rounding helps strengthen components against crack propagation as well.

Dimensional Inspection and Tolerances

Confirm all critical to function dimensions and 3D geometries match engineering requirements and product specifications before proceeding to secondary operations or customer delivery. Record data trends.

Common Errors and Troubleshooting

Pay close attention to these known CNC machining fault modes when inspecting finished pieces for accuracy:

● Chatter marks - Insufficient rigidity during cutting passes

● Tapered walls - Improperly trammed or aligned machine axes

● Steps in floors - Dull cutters with reduced chip loads

● Overcut radii - Excessive tool stick out and deflection

Thoughtfully tune operating parameters and mechanical adjustments until achieving satisfactory tolerance and surface finish capability. Eliminate the root cause - don’t just treat one-off symptoms.

Maintenance Tips for CNC Machines

Consistently performing scheduled preventative maintenance extends the productivity and lifespan of CNC equipment. Follow the OEM recommendations for cleaning methods, lubricants, and component replacement intervals.

Daily, Weekly and Monthly Checklists

● Blow off metal chips and debris near moving components using compressed air after operations

● Vacuum coolant tanks and chip conveyors to avoid clogging sensitive pumps and tooling

● Check machine structure bolts for any loosening due to vibration

● Lubricate linear rails, ballscrews and gear cases per guidance

● Inspect machine wiring for rodent or moisture damage

Tool Wear and Replacement

Replace or resharpen cutting bits immediately once tolerances start to suffer or finish quality degrades. Worn tools increase heat and forces, accelerating component fatigue. Proactively managing tooling condition prevents damage cascades.

Software and Firmware Updates

Import updated G-code postprocessors, machine interfaces and motor control firmware from vendors when available to fix bugs and unlock new capabilities. However, carefully test any revisions adequately before relying upon for production.

CNC Programming Basics (Optional for Beginners)

While generating optimized toolpaths from CAD files involves specialty CAM software expertise, beginners can start learning fundamentals with these concepts:

Intro to G-Code and M-Code

These instruction sets use alphanumeric formats to control axes motion, spindle actions, coolant states and other CNC functions. Mastering code structures helps operators program manually or troubleshoot files.

CAM Software Overview

Powerful interface programs like Fusion 360, MasterCAM and SolidWorks translate 3D models into machining operations, accounting for fixtures, tools and stock. The output is simulatable G-code.

Editing and Optimizing CNC Code

Understanding how to modify speeds, feeds, tool selections within code files allows refining cycle times, quality factors and tool loads. But changes can also introduce new problems if unfamiliar with underlying calculations.

Conclusion

Learning to safely and efficiently operate CNC machining centers requires studying key concepts like coordinate systems and G-code programming before attempting cutting. Additionally, properly preparing raw materials, creating fixtures, and selecting suitable cutting tools are all vital for success.

Carefully stepping through important procedures like defining machine zero, mounting workpieces, loading programs, and calibrating offsets will build core competencies over time. Gradually implement speeds and feed rates that optimize cycle times without compromising finish quality or accuracy.

Consistently maintaining CNC equipment and inspecting parts for errors allows continually dialing in tolerances and surface finishes towards optimum performance. Mastering these fundamental principles of CNC usage is challenging but very rewarding.

LED Street Lamp Test Specification

    LED street lights are currently one of the key implementation methods to save energy and reduce carbon, all countries in the world have been in full swing to replace the original traditional street lights with LED street lights, and the new street is directly limited to the use of LED street lights to save energy. At present, the world LED street lamp market size of about 80 million, LED lamp light source whether it is heat, service life, output spectrum, output illuminance, material characteristics, are different from traditional mercury lamp or high-pressure sodium lamp. The test conditions and test methods of LED street lights are different from traditional lamps. Lab Companion collected the reliability test methods related to LED street lights at present and provide you with reference to help you understanding the related tests about LED.

LED street lamp test specification abbreviation:

LED street lamp test standard specification, LED street lamp test method technical specification, LED street lamp standard and test method, night landscape engineering semiconductor lighting device components product technical specification, semiconductor lighting night landscape engineering construction quality acceptance technical specification, IEC 61347LED power supply safety regulation

LED street lamp test specification conditions:

CJJ45-2006 Urban road lighting design standard, UL1598 lamps safety standard, UL48 wire and cable safety standard, UL8750 light-emitting diode safety standard, CNS13089 light-emitting diode large lamp durability Test - pre-burning test - outdoor, Waterproof Test: IP65, American Standard for LED lamps, EN 60598-1, EN 60598-2 Street lamp test

LED large lamp quality certification test project:

Temperature cycle, temperature and humidity cycle, high temperature preservation, moisture resistance, vibration, shock, continuous power, salt water spray, acceleration, solder heat resistance, solder adhesion, terminal strength, natural drop, dust test

LED large lamp quality certification test conditions:

Temperature cycle: 125℃(30min)←R.T.(5min)→-65℃(30min)/5cycle

LED street lamp (light-emitting diode outdoor display with large lights) failure determination:

a. The axis light is lower than the residual rating of 50%

b. Forward voltage is greater than 20% of the rated value

c. Reverse current greater than 100% of the rated value

d. The half height wave length and half power Angle of the light exceed the limited maximum value or the limited minimum value meet the above conditions, and determine the failure of the LED street lamp

Note: The luminous efficiency of LED street lamp is recommended to be at least 45lm/W or above (the luminous efficiency of LED light source must be about 70 ~ 80lm/W)

High temperature storage: maximum storage temperature 1000 hours [special level 3000 hours]

Moisture resistance: 60℃/90%R.H./1000 hours [characteristic level 2000 hours]/ applying bias

Brine spray: 35℃/ concentration 5%/18 hours [24 hours special level]

Continuous power: maximum forward current 1000 hours

Natural fall: Fall height 75cm/ fall times 3 times/fall material smooth maple wood

Dust test: continuous 360 hours of 50℃ ring temperature test

Vibration: 100 ~ 2000Hz, 196m/s^2, 48 hours

Impact: Grade F[Acceleration 14700m/s^2, pulse amplitude 0.5ms, six directions, three times in each direction]

Equal acceleration: Acceleration is applied in all directions (class D: 196000 m/s^2) for 1 minute

Solder heat resistance: 260℃/10 seconds /1 time

Solder adhesion: 250℃/5 seconds

Terminal strength

LED large lamp batch quality test project:

Terminal strength, solder heat resistance, temperature cycle, moisture resistance, continuous power, high temperature storage

LED large lamp batch quality test conditions:

Moisture resistance: 60℃/90%R.H./168 hours (no failure)/500 hours (one failure allowed)[test number 10 / apply bias]

Continuous power on: maximum forward current /168 hours (no failure)/500 hours (one failure allowed)[test number 10]

High temperature storage: maximum storage temperature /168 hours (no failure)500 hours (one failure allowed)[test number 10]

Solder heat resistance: 260℃/10 seconds /1 time

Solder adhesion: 250℃/5 seconds

LED large lamp regular quality test project:

Vibration, shock, acceleration, moisture resistance, continuous power, high temperature preservation

Regular quality test conditions for LED large lights:

Moisture resistance: 60℃/90%R.H./1000 hours

Continuous power: maximum forward current /1000 hours

High temperature storage: Maximum storage temperature /1000 hours

Vibration: 100 ~ 2000Hz, 196m/s^2, 48 hours

Impact: Grade F[Acceleration 14700m/s^2, pulse amplitude 0.5ms, six directions, three times in each direction]

Equal acceleration: Acceleration is applied in all directions (class D: 196000 m/s^2) for 1 minute

LED large lamp screening test project:

Acceleration test, temperature cycle, high temperature preservation, pre-burning test

LED large light screening test conditions:

Constant acceleration test: Apply acceleration (grade D: 196000 m/s^2) in each direction for 1 minute

Temperature cycle: 85℃(30min)←R.T.(5min)→-40℃(30min)/5cycle

Pre-firing test: temperature (maximum rated temperature)/ current (maximum rated forward current)96 hours

High temperature storage: 85℃/72 ~ 1000 hours

LED lamp life test:

More than 1000 hours of Life Test (Life Test), light attenuation < 3% [withered light]

More than 15,000 hours of Life Test (Life Test), light attenuation < 8%

Test Specification of LCD Display

    LCD Display, full name of Liquid Crystal Display, is a flat display technology. It mainly uses liquid crystal materials to control the transmission and blocking of light, so as to achieve the display of images. The structure of the LCD usually includes two parallel glass substrates, with a liquid crystal box in the middle, and the polarized light of each pixel is controlled by the rotation direction of the liquid crystal molecules through the voltage, so as to achieve the purpose of imaging. LCD displays are widely used in TV, computer monitors, mobile phones, tablet computers and other devices.

    At present, the common liquid crystal display devices are Twisted Nematic (TN), Super Twisted Nematic (Super Twisted Nematic), STN), DSTN(Double layer TN) and color Thin Film Transistors (TFT). The first three kinds of manufacturing basic principles are the same, become passive matrix liquid crystal, and TFT is more complex, because of the retention of memory, and called active matrix liquid crystal.

    Due to liquid crystal display has the advantages of small space, thin panel thickness, light weight, flat right-angle display, low power consumption, no electromagnetic radiation, no thermal radiation, it gradually replaces the traditional CRT image tube monitor.

LCD displays basically have four display modes: reflection, reflection transmission conversion, projection, transmission.

(1) The reflection type liquid crystal display itself does not emit light, through the light source in the space into the LCD panel, and then by its reflective plate will reflect the light to the eyes of people;

(2) The reflection transmission conversion type can be used as a reflection type when the light source in the space is sufficient, and the light source in the space is used as lighting when the light is not enough;

(3) Projection type is to use the principle of similar movie playback, the use of projected light department to project the image displayed by the liquid crystal display to the remote larger screen;

(4) The transmission type liquid crystal display completely uses the hidden light source as lighting.

Relevant Test Conditions:

AEC-Q200 Passive Component Stress Test Certification Specification for Automotive Industry

    In recent years, with the progress of multi-functional in-vehicle applications, and in the process of popularization of hybrid vehicles and electric vehicles, new uses led by power monitoring functions are also expanding, miniaturization of vehicle parts and high reliability requirements under high temperature environmental conditions (-40 ~ +125℃, -55℃ ~ +175℃) are increasing. A car is composed of many parts. Though these parts are large and small, they are closely related to the life safety of car driving, so every part is required to achieve the highest quality and reliability, even the ideal state of zero defects. In the automotive industry, The importance of quality control of auto parts is often over the functionality of parts, which is different from the needs of consumer electronics for the general people's livelihood, that is to say, for auto parts, the most important driving force of the product is often not [the latest technology], but [quality safety]. In order to achieve the improvement of quality requirements, it is necessary to rely on strict control procedures to check, the current automotive industry for parts qualification and quality system standards is AEC(Automotive Electronics Committee). The active parts designed for the standard [AEC-Q100]. The passive components designed for [AEC-Q200]. It regulates the product quality and reliability that must be achieved for passive parts.

Classification of passive components for automotive applications:

Automotive grade electronic components (compliant with AEC-Q200), commercial electronic components, power transmission components, safety control components, comfort components, communication components, audio components

Parts summary according to AEC-Q200 standard:

Quartz oscillator: Application range [tire pressure monitoring systems (TPMS), navigation, anti-lock brakes (ABS), airbags and proximity sensors In-vehicle multimedia, in-vehicle entertainment systems, backup camera lenses]

Automotive thick film chip resistors: Application [automotive heating and cooling systems, air conditioning, infotainment systems, automatic navigation, lighting, door and window remote control devices]

Automotive sandwich metal oxide varistors: Application [Surge protection of motor components, surge absorption of components, semiconductor overvoltage protection]

Low and high temperature surface mount solid molded chip tantalum capacitors: Application [fuel quality sensors, transmissions, throttle valves, drive control systems]

Resistance: SMD resistor, film resistor, thermistor, varistor, automotive vulcanization resistance, automotive precision film wafer resistance array, variable resistance

Capacitors: SMD capacitors, ceramic capacitors, aluminum electrolytic capacitors, film capacitors, variable capacitors

Inductance: Reinforced inductance, inductor

Other: LED thin film alumina ceramic cooling substrate, ultrasonic components, overcurrent protection SMD, overtemperature protection SMD, ceramic resonator, automotive PolyDiode semiconductor ceramic electronic protection components, network chips, transformers, network components, EMI interference suppressors, EMI interference filters, self-recovery fuses

Passive device stress test grade and minimum temperature range and typical application cases:

Note: Certification for applications in higher grade environments: Temperature grades must have a product life worst-case and application design, i.e. at least one batch of each test must be validated for applications in higher grade environments.

Number of certification tests required:

High temperature storage, high temperature working life, temperature cycle, humidity resistance, high humidity: 77 thermal shock: 30

Number of certification tests Note:

This is a destructive test and the component cannot be reused for other certification tests or production

Bellcore GR78-CORE Test Specification

Bellcore GR78-CORE is one of the specifications used in the early surface insulation resistance measurement (such as IPC-650). The relevant precautions in this test are organized for the reference of the personnel who need to carry out this test, and can also provide a preliminary understanding of this specification.

Test purpose:

Surface Insulation resistance testing

1. Constant temperature and humidity test chamber: the minimum test conditions are 35°C±2°C/85%R.H, 85 ±2°C/85%R.H.

2. Ion migration measurement system: Allowing the insulation resistance of the test circuit (pattern) to be measured under these conditions, a power supply will be able to provide 10 Vdc / 100μA.

Test procedure:

a. The object to be measured is tested after 24 hours at 23℃(73.4℉)/50%R.H. condition.

b. Place limited Test patterns on an appropriate rack and keep the test circuits at least 0.5 inches apart, keep air flow and the rack in the furnace until the end of the experiment.

c. Place the shelf in the center of the constant temperature and humidity machine, align and parallel the test board with the air flow in the chamber, and lead the line to the outside of the chamber, so that the wiring is far away from the test circuit.

d. Close the furnace door and set the condition to 35 ±2°C, at least 85%R.H. and allow the furnace to spend several hours stabilizing

e. After 4 days, the insulation resistance will be measured and the measured value will be recorded periodically between 1 and 2,2 and 3,3 and 4, 4 and 5 using an applied voltage of 45 ~ 100 Vdc. Under the test conditions, the test is sent out the measured voltage to the circuit after 1 minute. 2 and 4 are periodically at an identical potential. And 5 periodically at opposite potentials.

f. This condition only applies to transparent or translucent materials, such as solder masks and conformal coatings.

g. As for multilayer printed circuit boards required for insulation resistance testing, the only normal procedure will be used for insulation resistance testing circuit products. Extra cleaning procedures are prohibited.

Method of conformity determination:

1. After the electron migration test is completed, the test sample is removed from the test furnace, illuminated from the back and tested at 10 x magnification, and will not be found to reduce the electron migration (filamental growth) phenomenon by more than 20% between the conductors.

2. adhesives will not be used as a basis for republication when determining compliance with the 2.6.11 test method of IPC-TM-650[8] to examine appearance and surface item by item.

Reasons why insulation resistance does not meet the requirements:

1. Contaminants weld the cells like wires on the insulating surface of the substrate, or are dropped by the water of the test furnace (chamber)

2. Incompletely etched patterns will reduce the insulation distance between conductors by more than permitted design requirements

3. Chafes, breaks, or significantly damages the insulation between conductors

Burn-in is an electrical stress test that employs voltage and temperature to accelerate the electrical failure of a device. Burn-in essentially simulates the operating life of the device, since the electrical excitation applied during burn-in may mirror the worst-case bias that the device will be subjected to in the course of its use able life. Depending on the burn-in duration used, the reliability information obtained may pertain to the device's early life or its wear-out. Burn-in may be used as a reliability monitor or as a production screen to weed out potential infant mortalities from the lot.

Burn-in is usually done at 125 deg C, with electrical excitation applied to the samples. The burn-in process is facilitated by using burn-in boards (see Fig. 1) where the samples are loaded. These burn-in boards are then inserted into the burn-in oven (see Fig. 2), which supplies the necessary voltages to the samples while maintaining the oven temperature at 125 deg C. The electrical bias applied may either be static or dynamic, depending on the failure mechanism being accelerated.

JEDEC, a standardization organization in the semiconductor industry, develops industrial standards in solid state electronics (semiconductor, memory), established for more than 50 years, is a global organization. The standards it has formulated are many industries take over and adopt. It's technical data are open and free of charge, only some of the data need to be charged. So you can go to the official website to register and download, the content contains the definition of professional terms, product specifications, test methods, reliability test requirements... It covers a wide range of topics.

JEP122G-2011 Failure mechanism and model of semiconductor components

Accelerated life tests are used to identify potential semiconductor failure causes in advance and estimate possible failure rates. The relevant activation energy and acceleration factor formulas are provided in this section for estimation and failure rate statistics under accelerated life tests.

Recommended equipment: high and low temperature test chamber, hot and cold shock test chamber, highly accelerated life test chamber, SIR Surface insulation resistance measurement system

JEP150.01-2013 Stress test drive failure mechanism associated with assembly of solid state surface mount components

GBA and LCC are attached to the PCB, using a more commonly used set of accelerated reliability tests to evaluate the heat dissipation of the production process and product, to identify potential failure mechanisms, or any reason that may cause error failure.

Recommended equipment: high and low temperature test chamber, hot and cold shock test chamber, highly accelerated life test chamber

JESD22-A100E-2020 Cycle temperature and humidity bias surface condensation life test

Test the reliability of non-sealed solid state devices in humid environments through temperature cycling + humidity + current bias. This test specification adopts the method of [temperature cycling + humidity + current bias] to accelerate the penetration of water molecules through the external protective material (sealant) and the interface protective layer between the metal conductor. Such a test will cause condensation on the surface. It can be used to confirm the corrosion and migration phenomenon of the surface of the product to be tested.

Recommended equipment: high and low temperature test chamber

JESD22-A101D.01-2021 Steady-state temperature and humidity bias life test

This standard defines the methods and conditions for performing temperature-humidity life tests under applied bias to assess the reliability of non-airtight packaged solid-state devices (e.g., sealed IC devices) in humid environments.

High temperature and humidity conditions are used to accelerate moisture penetration through external protective materials (sealants or seals) or along the interface between external protective coatings and conductors and other through parts.

Recommended equipment: high and low temperature test chamber

JESD22-A102E-2015 package IC unbiased PCT test

To evaluate the integrity of non-airtight packaged devices against water vapor in a condensed or saturated water vapor environment, the sample is placed in a condensed, high-humidity environment under high pressure to allow water vapor to enter the package, exposing weaknesses in the package, such as delamination and metallization layer corrosion. This test is used to evaluate new package structures or updates of materials and designs in the package body. It should be noted that there will be some internal or external failure mechanisms in this test that do not match the actual application situation. Since absorbed water vapor reduces the glass transition temperature of most polymer materials, an unreal failure mode may occur when the temperature is higher than the glass transition temperature.

Recommended equipment: Highly accelerated life test chamber

JESD22-A104F-2020 Temperature cycle

The temperature cycle (TCT) test is the reliability test of the IC part subjected to extremely high temperature and extremely low temperature, back and forth temperature conversion between the test, the IC part is repeatedly exposed to these conditions, after the specified number of cycles, the process is required to specify its temperature change rate (℃/min), in addition to confirm whether the temperature is effectively penetrated into the test product.

Recommended equipment: thermal shock test chamber

JESD22-A105D-2020 Power and temperature cycle

This test is applicable to semiconductor components affected by temperature. In the process, the test power supply needs to be turned on or off under the specified high and low temperature difference conditions. The temperature cycle and power supply test are to confirm the bearing capacity of the components, and the purpose is to simulate the worst situation that will be encountered in practice.

Recommended equipment: thermal shock test chamber

JESD22-A106B.01-2016 Temperature shock

This temperature shock test is carried out to determine the resistance and impact of semiconductor components to sudden exposure to extreme high and low temperature conditions. The temperature change rate of this test is too fast to simulate the real actual use. The purpose is to apply more severe stress on semiconductor components, accelerate the damage of their vulnerable points, and find out the possible potential damage.

Recommended equipment: thermal shock test chamber

JESD22-A110E-2015 HAST highly accelerated life test with bias

According to JESD22-A110 specifications, both THB and BHAST are used to test components at high temperature and humidity, and the test process needs to be biased to accelerate the corrosion of components. The difference between BHAST and THB is that they can effectively shorten the test time required for the original THB test

Recommended equipment: Highly accelerated life test chamber

JESD22A113I plastic surface mount device prior to reliability testing

For non-enclosed SMD parts, pre-treatment can simulate the reliability problems that may occur during the assembly of the circuit board due to the damage caused by packaging moisture, and identify potential defects in the reflow assembly of SMD and PCB through the test conditions of this specification.

Recommended equipment: high and low temperature test chamber, hot and cold shock test chamber

JESD22-A118B-2015 Unbiased high-speed accelerated life test

To evaluate the resistance of non-airtight package components to moisture under non-biased conditions, confirm their moisture resistance, robustness and accelerated corrosion and aging, which can be used as a test similar to JESD22-A101 but at a higher temperature. This test is a highly accelerated life test using non-condensation temperature and humidity conditions. This test must be able to control the rising and cooling rate in the pressure cooker and the humidity during cooling

Recommended equipment: Highly accelerated life test chamber

JESD22-A119A-2015 Low temperature storage life test

In the case of no bias, by simulating the low temperature environment to assess the ability of the product to withstand and resist low temperature for a long time, the test process does not apply bias, and the electrical test can be carried out after the test is returned to normal temperature

Recommended equipment: high and low temperature test chamber

JESD22-A122A-2016 Power cycle test

Provides standards and methods for solid-state component package power cycle testing, through biased switching cycles that cause uneven temperature distribution inside the package (PCB, connector, radiator), and simulates standby sleep mode and full load operation, as well as life cycle testing for associated links in solid-state component packages, This test complements and augments the results of the JESD22-A104 or JESD22-A105 tests, which cannot simulate harsh environments such as engine rooms or aircraft and space shuttles.

Recommended equipment: thermal shock test chamber

JESD94B-2015 Application-Specific qualifications use knowledge-based testing methods

Testing devices with correlated reliability testing techniques provides a scalable approach to other failure mechanisms and test environments, and life estimates using correlated life models

Recommended equipment: high and low temperature test chamber, hot and cold shock test chamber, highly accelerated life test chamber

Specification for Ground Solar Radiation Simulation Test

    The purpose of this test method is to determine the physical and chemical effects of components and equipment exposed to solar radiation on the Earth surface (e.g. The main characteristics of the simulated environment in this experiment are the solar spectral energy distribution and intensity of received energy under the control of temperature and humidity in the test environment. There are three procedures in the test mode (Procedure A: thermal effect evaluation, procedure B: degradation effect evaluation, procedure C: photochemical effect evaluation).

Applicable products:

Electronic products that will be used outside the home for a long time, such as: laptops, mobile phones, MP3&MP4, GPS, automotive electronics, digital cameras, PDAs, low-cost laptops, easy to carry laptops, video cameras, Bluebud headphones

Test requirements:

1. Spectral energy distribution shall meet the requirements of the specification

2. Illuminance: 1.120KW/m^2 (±10%)=[300-400um, 63 w/m2][The total global radiation of the earth's surface from the sun and the sky vertical is 1.120KW/m^2]

3. Temperature and humidity 40℃(±2)/93%(±3)R.H.

4. This test needs to control the humidity environment

5. During irradiation, the temperature in the box rises to the specified temperature (40℃, 55℃) at a linear rate.

6. The temperature in the box should start to rise 2 hours before irradiation

7. The temperature in the dark chamber should be decreased linearly and maintained at 25℃

8. Temperature error: ±2℃

9. The temperature measurement point in the box is taken from the test distance of 1m from the specimen or half of the box wall distance (the smaller one)

Spectral energy distribution and tolerance error range of Xenon lamp (according to the requirements of the International Illuminance Commission CIE)

The xenon lamp weather testing machine is not lit, but the spectrum output by its xenon lamp must be output in accordance with the requirements of the International Illuminance Commission CIE. Therefore, the equipment manufacturer of the weather testing machine must have the equipment (spectrometer) and technical capability to verify the xenon lamp spectrum (provide xenon lamp verification report).

Test procedure evaluation description:

According to IEC68-2-5&IEC-68-2-9, there are three kinds of test methods for light resistance test, which can be divided into program A: thermal effect, B: degradation effect, C: photochemistry. Among these three methods, procedure A is the most severe test method, which will be detailed in the following article.

Three test procedures: Procedure A: thermal effect (most severe natural conditions), B: degradation effect (22.4KWh/m2 per day), C: photochemistry

Program A: Thermal effect

Test conditions: 8 hours of exposure, 16 hours of darkness, a total of 24 hours per cycle, three cycles were required, and the total exposure of each cycle was 8.96KWh/m2

Procedure A test precautions:

Instructions: In the test process of program A, the xenon lamp is not lit immediately at the beginning of the test, according to the requirements of the code, it must be lit after 2 hours of the test, closed at 10 hours, and the total irradiation time of a cycle is 8 hours. During the lighting process, the temperature in the furnace rises linearly from 25℃ to 40℃(satisfying most environments in the world) or 55℃(satisfying all environments in the world), and decreases linearly at 10 hours to 25℃ for 4 hours, with a linear slope (RAMP) of 10 hours.

Test procedure B: Degradation effect

Test conditions: Temperature and humidity in the first four hours of the test was (93%), irradiation for 20 hours, darkness for 4 hours, a total of 24 hours per cycle Total exposure for each cycle was 22.4KWh/m2 cycles: 3(3 days: commonly used), 10(10 days), 56(56 days)

Procedure B test precautions:

Instructions: Procedure B test is the only test condition for humidity control during light resistance test in IEC68-2-5 specification. The specification requires that the temperature and humidity conditions are (40±2℃/93±3%) within four hours from the beginning of the test [supplementary description in IEC68-2-9] humidity environment, which should be paid attention to when conducting the test. At the beginning of the program B test, the temperature was raised from 25℃ linear slope (RAMP: 2 hours) to 40℃ or 55℃, maintained for 18 hours, and then the linear cooling (RAMP: 2 hours) returned to 25℃ for 2 hours to complete a cycle of experiments. Remarks: IEC68-2-9 = Solar Radiation Test Guidelines

Test procedure C: Photochemistry (Continuous Irradiation)

Test conditions: 40℃ or 55℃, continuous irradiation (depending on the time required)

Procedure C test precautions:

Note: After the linear temperature rise (RAMP: 2 hours) from 25℃ to 40℃ or 55℃, the continuous irradiation test was carried out at a fixed temperature before the end of the test. The irradiation time was determined according to the characteristics of the product to be tested in the test, which was not clearly specified in the specification.

Instructions:

Early temperature cycle tests only look at the air temperature of the test furnace. At present, according to the requirements of relevant international norms, the temperature variability of the temperature cycle test refers not to the air temperature but the surface temperature of the product to be tested (such as the air temperature variability of the test furnace is 15°C/min, but the actual temperature variability measured on the surface of the product to be tested may only be 10~11°C/min), and the temperature variability that will rise and cool down also needs symmetry, repeatability (the rise and cooling waveform of each cycle is the same), and linear (the temperature change and cooling speed of different loads is the same). In addition, lead-free solder joints and part life assessment in advanced semiconductor manufacturing processes also have many requirements for temperature cycle testing and temperature shock, so its importance can be seen (such as: JEDEC-22A-104F-2020, IPC9701A-2006, MIL-883K-2016). The relevant international specifications for electric vehicles and automotive electronics, their main test are also based on the temperature cycle test of the surface of the product (such as :S016750, AEC-0100, LV124, GMW3172).

Specification for the product to be tested surface temperature cycle control requirements:

1. The smaller the difference between the sample surface temperature and the air temperature, the better.

2. Temperature cycle rise and fall must be over temperature (exceed the set value, but not exceed the upper limit required by the specification).

3. The surface of the sample is immersed in the shortest time. Time (soaking time is different from residence time).

Thermal stress testing machine (TSC)of LAB COMPANION in the temperature cycle test of the product to be tested surface temperature control features:

1. You can choose [air temperature] or [temperature control of the product to be tested] to meet the requirements of different specifications.

2. The temperature change rate can be selected [equal temperature] or [average temperature], which meets the requirements of different specifications.

3. The deviation of temperature variability between heating and cooling can be set separately.

4. Overtemperature deviation can be set to meet the requirements of the specification.

5.[temperature cycle] and [temperature shock] can be selected table temperature control.

IPC requirements for temperature cycle test of products:

PCB requirements: The maximum temperature of the temperature cycle should be 25°C lower than the glass transfer point temperature (Tg) value of the PCB board.

PCBA requirements: The temperature variability is 15°C/min.

Requirements for solder:

1. When the temperature cycle is below -20 °C, above 110 °C, or contains the above two conditions at the same time, more than one damage mechanism may occur to the solder lead welding connection. These mechanisms tend to accelerate each other, leading to early failure.

2. In the process of slow temperature change, the difference between the sample temperature and the air temperature in the test area should be within a few degrees.

Requirements for vehicle regulations: According to AECQ-104, TC3(40°C←→+125°C) or TC4(-55°C←→+125°C) is used in accordance with the environment of the engine room of the car.