Designing and testing robust industrial computing solutions
Amplicon has gained an unrivalled experience over the past 33 years in the design, manufacture and distribution of computer products, systems and solutions for industrial applications. They have the ability to tailor systems to meet application and environmental requirements across a wide range of industries. Their equipment would typically be destined for use in factories, transport, warehousing, laboratories and military COTS. Like all Amplicon products, their industrial computing systems are manufactured under strict quality management procedures certified to ISO9001:2000.
The first step in designing an industrial computing system is to be aware what product standards and directives have to be met. Industrial computing products would typically be covered by areas related to safety and electromagnetic compatibility (EMC). If the product is to be put onto the European Market, it will need to be CE Marked to indicate that it has complied with all associated directives.
In designing a computing system, there are a number of main building components that influence the look, feel, performance, reliability, repeatability and robustness of the end product. These include the storage drives (HDD, Solid State, CompactFlash, CD drives and FDD), Memory, Central Processing Unit (CPU), processor cooler, Power Supply Unit (PSU) or redundant PSU, Motherboard or Single Board Computer (SBC) and Backplane combination, total chassis cooling mechanism and finally the Chassis.
A standard 4U chassis is highly scaleable and its versatility lends itself to many end applications and environments. Hence, in building a computing system, the industry and application in question have to be taken into consideration. Different applications may also require different IP ratings and certifications.
For the most extreme conditions and out-of-the-office applications, rugged mobile computer systems provide the ultimate in notebook and tablet computing. Rugged mobile computers feature protection against dust, debris and water by using the latest materials and sealing techniques. The rugged mobile computers offered are largely based on Intel's 855GME chipset. This highly efficient chipset and associate component subsets, including processor and memory offer the performance to allow efficient fully sealed fanless rugged computers to be produced. Furthermore, flexible design techniques allow their rugged mobile computers to support plug-in PCI or ISA expansion cards. In this design, mobile application processors and associate fanless coolers are used; and for space conservation, a 2.5” HDD is used. This greatly improves the device shock and vibration tolerance.
For automotive applications, the computing system will be exposed to a lot of vibration and dust; hence it needs to be more robust in its total design. Any computing device made for use in the automotive industry needs e mark certification. The recommended design would be an embedded, fanless solution. Using a fully enclosed device, where the chassis acts as a cooling mechanism for the device
For medical, pharmaceutical and food applications the high tech modular industrial PC design is recommended. This can be easily configured to meet customer needs by including a touch screen and expansion slots for plug-in boards to further expand the system and provide additional features. The system can be operated using a touchscreen or via a rugged IP54/65 rated keyboard. The completely sealed stainless steel housing makes the system meet the IP specified protection norms and requirements for these industries.
Generally when designing an industrial computing system, a single board computer (SBC) solution will offer greater repeatability (typically 5 years). These products have a more versatile range of options and are revision controlled with a longer life cycle than motherboards. For projects requiring repeatability in excess of 5 years, spares requirements are calculated to support the product over its desired life cycle.
The PSU unit selection is dependant on the sum of the individual component power requirements, as well as the required availability of the device. It is also important to allow for any future increase in power demands, due to expansion of the original system. Industrial computing devices are designed for 24/7 use and in some cases a redundant PSU is required. These comprise of a minimum of two independent PSU modules housed in a single cage. The device needs to be capable of running effectively with just one of the modules operating. During normal mode there will be load sharing between both modules. When a module becomes defective an audible and visual alarm will indicate which module requires replacement.
Once the right components are put together to produce an end prototype unit, tests are carried out to ensure that the device gets the CE Mark.
After ensuring that components and hence the end product as a whole conforms to the Restriction of the Use of Certain Hazardous Substances (RoHS) Directive, the product then can undergo conformance testing. All associated Amplicon products fully conform to the RoHS Directives.
Amplicon owns an extensive purpose-built EMC and conformance laboratory. Using the latest test equipment, they ensure all products conform to relevant international standards.
The primary objective of the CE Mark and associated product assessment is to provide the customer and enforcement bodies with the evidence that the devices placed on the market conform to the essential requirements of all associated directives.
For most electrical devices the safety is covered by the Low Voltage Directive (LVD). This applies to nearly all electrical equipment designed for use between 50V and 1000V AC or between 75V and 1500V DC. This refers to the electrical input or output voltages, not just the supply voltage powering the device. This directive has a huge scope and applies to industrial, domestic and many other environments.
Electromagnetic interference (EMI) is a serious and increasing form of environmental pollution. Its effects could range from minor crackles on broadcast reception to potential fatal accidents due to corruption of safety critical monitoring and control systems. Various forms of EMI can cause electrical and electronic malfunctions and may even have a direct effect on human tissue. The EMC Directive’s main objective is to minimise the effect caused by EMI from electrical and electronic devices.
Shock and vibration tests are also carried out on the range of products recommended for use in applications under extreme ambient conditions. Once the pre-conformance tests and modifications are made to produce a certified design, the product is then manufactured.
All of Amplicon’s industrial computing systems are revision controlled and undergo an extensive soak-test before shipment. This eliminates the shipment of faulty or incomplete systems.
About the Author: Leon Mengot, product manager at Amplicon Industrial Computers.