Life Expectancy of Commercial Electronics
I came across an article on the life expectancy of commercial electronics. Surprisingly, the time frame was relatively short for most items. For example, the longest item on that list was a flat panel TV at 7.4 years. Another was a desktop computer at 5.9 years. I’ve visited plants where the control system hardware had been in place for well over 25 years. Obviously, we shouldn’t expect electronic hardware to last forever. Yet, given how crucial the plant’s machine control system is, I am often surprised by the age of automation hardware. Especially considering mechanical relays will eventually wear out and electrolytic capacitors will degrade and ultimately fail.
Additionally, if you expose solid state components high heat or continuous heat cycles, they will fail too. Over the years, I’ve seen many common failures. Along the way, I’ve learned some tips to help mitigate common causes of electronics failures.
Combating the Most Common Cause of Electronics Failure
I’ve had the opportunity to be part of a number of control system retrofits. Where I have seen the most failures are typically in the panel or chassis power supplies. These produce the most heat and often have many electrolytic capacitors. In my research, heat appears to be the most common electronic component failure.
If you have chassis or stand-alone DC power supplies in your automation system, I would make the following recommendations. If the power supply is over 10 years old, consider replacing it with a new one. Typically, the power supply is not a huge cost and without it nothing will operate. Take time to periodically clean the cabinet. With power removed from the cabinet, vacuum the panel out and lightly blow out accumulated dust.
Check out the heat electronics are being exposed to. The higher the temperature, the faster that electronics are likely to fail. Most electronics can operate in temperatures up to 140 F. However, that lifespan may be expected to be half or less when exposed to 80 F. If you are exposing your electronics above 110 F, consider cooling or ventilation of the cabinet. Even if the electronics have internal cooling fans, check the operation regularly. You may also want to lightly blow out the accumulated dust from the heatsinks. Install some power conditioning or surge suppression equipment for critical electronics. This would be for items like Control System HMI stations, Control System processor racks or chassis, and Ethernet Networking equipment.
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Brian Olsen, Interstates Control Systems Developer