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Industrial Systems Can Benefit from Consumer Product Designs, Assuming Appropriate Caution is Taken

There’s an intriguing good and bad relationship between the design of mass market consumer products versus products for industrial applications. On the hardware side, industrial designers can leverage and benefit from the many component attributes of the consumer product world. Among these are low power, low voltage ICs; high volume, low cost passive, active, and packaging components; and a wide range of small yet flexible user interface options (displays and keypads).

On the software side, there are “canned” routines for handling I/O functions such as drivers, connectivity, user interfaces; system and link security and encryption routines; and numerical and mathematical functions, to cite just a few.

For these reasons, it makes sense for engineers designing industrial applications to make use of consumer product components and other resources where it makes sense.

However, there are major differences between the two worlds, and even downsides to designing by leaning too heavily on the mandates and mindset of mass-market product design guidelines and objectives. Here are a dozen which stand out:

1) Scope: industrial products are focused on doing one or a few things well and doing them reliably. For most industrial products, it’s a case of “less is more” – in other words, offering fewer features and functions, and even with less flexibility, but implementing them with rock-solid software and consistent hardware. In contrast, while some consumer products are similarly focused, many suffer from mission and feature “creep.”

2) The user interface: consumer products often soon become complicated to use, with multilayered drop-down menus, an abundance of user options, and even constant operating system queries to the user. In contrast, the industrial user interface must be direct, to the point, and with user choices that are clearly relevant.

3) Keypad complexity: Industrial products have dedicated single-function keys for high priority functions, rather than “soft keys” which are defined and re-defined by the system software during the operating modes.

4) Regulatory mandates: Consumer products are tightly bounded by EMI/RFI emission specifications which are largely a function of their power supply wattage. Industrial designs also must meet emission regulations, but they are often less stringent given the environment in which they operate. However, the higher voltages of many industrial systems place more stringent requirements on physical and safety design, including clearance and creepage dimensions of pc board circuit layout.

Figure 1: The Panasonic AFPX-C14R PLC has an industrial design, distinct from that of typically aesthetic consumer devices. (Image source: Panasonic)

5) Protection: Industrial products must be protected against ESD, spikes, noise, overvoltage, and many other maladies inherent to their environment; consumer products generally don’t need as high a level of protection again these disturbances.

6) Thermal issues: For many consumer products, cooling must be by natural convection only; hence, there is usually an array of cooling holes in their covers (and users must be sure not to block them). In contrast, many industrial applications assume a hotter ambient environment and even a closed cabinet, with minimal unforced airflow. Therefore, forced-air cooling must be factored into the system design.

7) Appearance: For consumer products, visual “appeal” is often as important as functionality and convenience; hence, the use of small buttons and often illegible labels. Industrial designs, on the other hand, favor usability and functionality over appearance, so the product enclosure, form factor, and labeling are often defined by the product’s primary functions, even if the result interferes with aesthetics. This is clearly seen in a programmable logic controller (PLC) such as the Panasonic AFPX-C14R, with its no-frills package, basic user display, and easily accessible wire connection terminals (Figure 1).

8) Power supply: In industrial designs, the power supply is the foundation for system reliability, stability, and longevity. The industrial power supply emphasizes design margins with respect to component tolerances, temperature range, noise, long-term performance, and overall robustness. Consumer products often use a marginal supply which just “gets by,” has little headroom, emphasizes low cost and long run time (if battery powered) and may not last long – there are countless stories of supplies (and therefore products) which failed after a year simply because their bulk capacitors dried out or swelled.

Figure 2: Capacitors for industrial applications, such as the THH9476M063W0250W from AVX, emphasize higher temperature tolerance and longer life operation. (Image source: AVX)

In contrast, the bill of materials (BOM) for industrial supplies often specifies higher temperature, longer life capacitors. For example, the THH9476M063W0250W capacitor in the AVX THH series is a 47 microfarad (µF) tantalum bulk component measuring 12 millimeters (mm) × 12.50 mm × 6 mm that is rated for 1000 or 2000 hours at 230⁰C (depending in suffix), and for 10,000 hours at 200⁰C (Figure 2). Although very few industrial applications will even reach these temperatures, it does mean the lifetime at more modest but still high levels will be orders of magnitude longer than the 1000 hour rating of standard grade devices at room temperature.

9) Physical connectivity: While consumer products often require multiple cables and connectors (although that is changing in some cases due to USB Type-C), consumer connectors are not rugged or latched: think USB, HDMI, and even the ubiquitous barrel connector for power supply adapters. In contrast, industrial designs use rugged connectors, often with locking mechanisms and retainers.

For basic transducer I/O wiring, they often use simple yet reliable terminal blocks which are easy to use (connect and disconnect) but would not be acceptable on a consumer product. The VI0921550000G from Amphenol Anytek is typical: this is a nine-position wire-to-board terminal block with screw down locking on the inserted wire; no wire conductor is exposed if the wire is stripped properly before being inserted (Figure 3).

10) Security: Many consumer products such as low-end video cameras or doorbells have little or no protection against hackers. That is unacceptable for industrial systems where a hacker can access internal information or create havoc on a production line. No need to explain this further!

Figure 3: Simple yet reliable terminal blocks are widely used in industrial applications, but would normally be unacceptable on a consumer product. (Image source: Amphenol Anytek)

11) Field upgrades: It’s common for consumer products with internet access – which is almost every product these days – to allow the vendor to download “upgrades”, often without an explicit approval from the user. As a result, features, functions, and more can change without user buy-in or understanding of their impact. Even worse, this “upgrade” capability is sometimes used as a cover for shipping a beta-version product, since it can be “fixed” in the field after shipment.

For industrial users, none of these conditions are acceptable: products must be fully tested when shipped, and any upgrades must be rare, explained in advance, and done at a time specified by the user.

12) Repair and obsolescence: The rate of new product introductions for consumer designs means that they are often discontinued within a few years; three to five years is very common. After that, replacement pc boards are unavailable (even if they are repairable) and their components may also be unavailable.

In contrast, industrial products are commonly in use for ten, fifteen, or more years. Therefore, replacement boards which are form, fit, and functional equivalents must be available during that period. That means that the latest, greatest IC may not be the right choice for an industrial product if the vendor is not willing to commit to the industrial market’s longevity and non-obsolescence requirements.

Conclusion

Industrial designers should definitely look at and consider using some of the components and approaches used in the design of consumer products, as these may offer attractive solutions to design challenges and objectives. However, it’s important to also recognize the distinct differences between the priorities of consumer versus industrial products, and where use of consumer product performance standards and components may compromise the industrial product viability.

About this author

Image of Bill Schweber

Bill Schweber is an electronics engineer who has written three textbooks on electronic communications systems, as well as hundreds of technical articles, opinion columns, and product features. In past roles, he worked as a technical web-site manager for multiple topic-specific sites for EE Times, as well as both the Executive Editor and Analog Editor at EDN.

At Analog Devices, Inc. (a leading vendor of analog and mixed-signal ICs), Bill was in marketing communications (public relations); as a result, he has been on both sides of the technical PR function, presenting company products, stories, and messages to the media and also as the recipient of these.

Prior to the MarCom role at Analog, Bill was associate editor of their respected technical journal, and also worked in their product marketing and applications engineering groups. Before those roles, Bill was at Instron Corp., doing hands-on analog- and power-circuit design and systems integration for materials-testing machine controls.

He has an MSEE (Univ. of Mass) and BSEE (Columbia Univ.), is a Registered Professional Engineer, and holds an Advanced Class amateur radio license. Bill has also planned, written, and presented on-line courses on a variety of engineering topics, including MOSFET basics, ADC selection, and driving LEDs.

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