Rugged Design
What is a Rugged Device?
A rugged device is a computer specifically designed to operate reliably in harsh environments and conditions, such as strong vibrations, extreme temperatures, and wet or dusty conditions. They are built for rough use, not only in the external housing but also in the internal components and cooling arrangements. Typical environments for rugged laptops, tablet PCs, and PDAs are public safety, field service, manufacturing, retail, healthcare, transportation, warehouse and logistics, and the Defence.
Virtually all rugged computers share an underlying design philosophy of providing a controlled environment for the installed electronics.
Rugged computers are engineered to operate in the face of multiple challenges, including:
Electronic components are selected to withstand higher and lower operating temperatures than typical commercial components. Design engineering decisions such as reducing cabling, the addition of liquid cooling and heat sinks, and rugged materials ensure performance in harsh environments. The right choice of high-quality components, high-tech material, and mechanical design is our core competence. Also, related know-how about assembling, connecting, and mounting is a necessity.
Ingress Protection
IP sealing is needed in various applications to seal the products against liquids, dust, or humidity. Winmate is following the standard testing procedures to test the product design.
We provide various levels of mechanical dust & water-resistant design and offer ruggedized industrial flat-panel LCDs. These ruggedized products are highly reliable, withstand shocks and vibrations, survive extreme temperatures and corrosive environments. Exterior materials like dust/ water can be very destructive to any equipment over time.
Winmate Ingress Protection Technology
There are many different possibilities for sealing the product. The most typical sealing is the front sealing. After mounting, the product is sealed for dust and water protection depending on the tested grade. Other parts besides the front sealing include the connectors, rear, top, and complete sealing, depending on the application.
Tests are carried out to ensure the degree of sealing with the products and check if there is any water, dust, or dirt passing our sealing design.
- Glass or touchscreen to the front bezel
- Internal dust sealing from LCD to the glass or touchscreen
- Prepared sealing for mounting to the equipment
Besides the water sealing, other liquids for cleaning, disinfection, or saltwater are possible environments, which influence the choice of material and the methods for sealing.
Also, direct sunlight needs to be considered in this choice, as UV light can destroy the polymer structure of most sealing materials. The right choice of material is a core competence of Winmate engineering and design capabilities.
NEMA Enclosure Rating and Comparison to IP Code
NEMA (National Electrical Manufacturers Association) sets the industry standards in the USA for electrical equipment enclosures. In non-hazardous locations, there are several different NEMA ratings for specific enclosure types, their applications, and the environmental conditions they are designed to protect against when completely and properly installed.
The following provides an overview of the NEMA types. For complete definitions, descriptions, and test criteria, see the National Electrical Manufacturers Association (NEMA) Standards Publication No. 250. The European Standards are determined by the Institute of Petroleum and are sometimes referred to as Ingress Protection (IP) numbers. The standards are listed below.
NEMA Enclosure Rating | Description | IP Classification Code | |
---|---|---|---|
1. | NEMA 1 | constructed for indoor use to provide a degree of protection to personnel against incidental contact with the enclosed equipment and to provide a degree of protection against falling dirt. | IP20 |
2. | NEMA 2 | Same as NEMA 1 including protection against dripping and light splashing of liquids. | IP21 |
3. | NEMA 3 | Enclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt, rain, sleet, snow, and windblown dust; and that will be undamaged by the external formation of ice on the enclosure. | IP54 |
3R. | NEMA 3R | Same as NEMA 3 excluding protection against windblown dust. | IP24 |
3S. | NEMA 3S | nclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt, rain, sleet, snow, and windblown dust; and in which the external mechanism(s) remain operable when ice laden. | IP54 |
4, 4X. | NEMA 4 | Enclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt, rain, sleet, snow, windblown dust, splashing water, and hose-directed water; and that will be undamaged by the external information of ice on the enclosure. | IP56 IP65 IP66 |
NEMA 4X | Same as NEMA 4 including protection against corrosion. | ||
5. | NEMA 5 | Enclosures constructed for indoor use to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt; against settling airborne dust, lint, fibers, and to provide a degree of protection against dripping and light splashing of liquids. | IP52 |
6, 6P. | NEMA 6 | Enclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt, rain, sleet, snow, windblown dust, splashing water, and hose-directed water; and that will be undamaged by the external information of ice on the enclosure. | IP67 |
NEMA 6P | Same as NEMA 6 including protection against the entry of water during prolonged submersion at a limited depth. | ||
12, 12K. | NEMA 12 | Enclosures constructed (without knockouts) for indoor use to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt; against circulating dust, lint, fibers, and against dripping and light splashing of liquids. | IP52 |
NEMA 12K | Same as NEMA 12 including enclosures constructed with knockouts. | ||
13. | NEMA 13 | Enclosures constructed for indoor use to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt; against circulating dust, lint, fibers, and against the spraying, splashing, and seepage of water, oil, and non-corrosive coolants. | IP54 |
Shock and Vibration Resistance
A rugged device must be able to withstand shocks and vibrations.With the choice of high-tech materials such as butyl rubber, ENR, high damping silicone, and SBR and the right mechanical design, Winmate guarantees the product compliance with the required industry standard. To prevent damages from during transportation, a suitable packing way is also considered.
Shock and Vibration Resistant Design
When designing rugged products Winmate performs environmental stress test in our internal laboratory. In-house testing facilities give our R&D engineers a possibility to detect potential problems during the early stage of product development and improve the design or material choice accordingly to prevent failure in mass production.
-
Vibration and Shock Test
The purpose of the vibration test is to check the mechanical resonance in all 3 directions (X, Y, and Z). With the testing result, our mechanical engineers can optimize the design and make the product most reliable for the usage. During and after this procedure the product needs to be 100% functional and no mal-function.
-
Drop Test
A drop test is a test to check the structural integrity of a product.
Temperature and Humidity
Rugged devices are subject to extreme weather. From freezing cold to peaking hot the device must be able to guarantee stable work no matter where the task takes you. Winmate test the ruggedness of its devices in low temperature (-20°C), high temperature (60°C), and humidity chambers.
Corrosion Resistance
Corrosion is a degradation of materials' properties caused by chemical reaction with their environments. For example, the corrosion of iron is due to interact with oxygen and water to produce rust.
Methods of Corrosion Prevention
Marine and electronic equipment are suffering from corrosion because of contamination by salt and water into the concrete. The proven methods of dealing with corrosion prevention are:
- Selecting anti-corrosion material
- Enclosure design to prevent corrosion
- Painting treatments on the surface
- Chemical conversion coating treatment on the surface
- Electroplate treatment on the surface
- Operating environment control
- Anodizing (Anodic Oxidation)
- Two ways of corrosion protection
- Positive Passivity: Anodic protection
- Negative Immunity: Cathodic protection
How Does Winmate Test Corrosion Resistance?
The salt spray test is a standardized test which widely used in the marine/ industrial products to evaluate different corrosion prevention methods.
Test Methods
The test period depends on the corrosion resistance of the coating; the more prevention of corrosion the longer the period in testing without showing appearances of corrosion.
Refer to IEC60945:2002, Section 8.12
Test sequence-1: Salt spray test, exposing for 2 Hours
At temperature 35C
Saline solution: 5% NaCl, PH 6.5 to 7.2
Quantity of fog: 1.0~ 2.0ml/80 cm2 / hour
Test sequence-2: Humidity storage test, exposing for 168 Hours
Storage Temperature: 40C
Humidity in chamber during storage: 93%
Above test sequences shall perform for 4 cycles
Data source: Dr. RollyLuo, Dept. of Advanced Electrochemistry & Corrosion Prevention, Material and Chemical Research Laboratories, Industrial Technology Research Institute, Taiwan.