These days most industrial grade fanless box PC’s from manufacturers such as CyberVisuell are very well built.
Use a Flash-Based Storage DriveTo get maximum reliability from an embedded system, it is good practice to avoid using anything with moving parts. This means traditional hard disk drives should be avoided – probably the most common component to fail in a PC is the spinning hard drive. Instead, opt for a Solid State Drive (SSD) or an industrial flash-based disk such as an Industrial Compact Flash. In addition, the SSD or Flash drive that you use needs to be designed for industrial usage, or “Industrial Grade”. This means it should have a wide temperature rating, and be designed for reliable performance under 24×7 operation for many years. One way of improving the performance and reliability of such drives is to use SLC flash, instead of the cheap MLC flash that is normally used in consumer grade SSD’s. SLC flash is more stable and has a much longer write-cycle life compared to MLC flash. However the cost per gigabyte is also higher, so SLC is typically used for the main operating system drive, rather than for bulk data storage. Another concern with flash drives is that they need to have a good “wear levelling” algorithm built in. This is because each cell of flash memory only allows a limited number of writes before it will fail. The wear levelling algorithm spreads out the write operations across many different cells of the drive, hence spreading the wear evenly and maximising the drive life.
Use an Embedded Operating System on your Fanless Box PCRegular operating systems such as Windows 7 are designed to be operated by a person all the time, rather than just to perform a few set tasks automatically in a remote unattended setting. Hence regular OS’s typically request and assume user interaction all the time – such as Windows security updates, or stopping and starting applications whenever needed. And when things don’t work the way they should, it is assumed that the operator can shut down and restart the PC, or request help to sort out the issue. In a remote or unattended scenario, however, these things become major problems. What happens if Windows automatically applies an update from the internet, and this forces a reboot of the system in the middle of a critical task? Or even worse, what if that Windows update prevents the PC from booting correctly, and prevents anyone from gaining remote access to it? The solution to this is to use an Embedded Operating System. For those familiar with Windows or Linux, the easiest way to do this is to use an Embedded variant of Windows or Linux. This offers several key advantages:
- The Embedded version is basically the same operating system so will run the same applications and drivers.
- Embedded OS’s include Filters – such as Write Filters to protect drive partitions and prevent system changes; or USB filters, to only allow particular USB devices to be accepted, such as keyboard/mouse.
- Operating system componentisation – allows you to remove parts of the OS that you don’t need, to minimise the disk and memory space needed.