The benefits of using a rack to keep your workbench tidy
There are also single-frame units for lighter total load weight such as the Bud Industries RR-1264- BT which is nearly as high as the C2F197823LG1 at 70 in., and which offers somewhat easier access to the front and back of its contents (Figure 4). These full-height floor racks may be too much for the bench-top development scenario, but there’s an attractive alternative: a shorter, 11” high rack such as the Hammond Manufacturing RCHV1900817BK1, which can be placed on the corner of the benchtop rather than next to it (Figure 5). Racks are not just for mounting of vendor-supplier instrumentation units, either. Many years ago, I was involved in the design of a controller for a large electromechanical test frame which had some frame-mounted switches that tripped when the piston’s excursion exceeded a set value. For initial testing we needed to emulate the limit switch closure but did not want to energize an actual frame.
and getting tangled in everything. The solution was straightforward: we placed a tabletop 19” rack on the corner of the bench and had the in-house model shop make a narrow rack panel with a cutout for the toggle switch array, thus giving it a fixed home. We even took further advantage of the new rack by mounting a few other small instruments in it and added some full-width shelves so we had a place for small boards which could not be easily rack mounted. The result was greater efficiency, fewer foolish mistakes, and fewer items disappearing when we weren’t looking! There’s an aspect of longevity in the rack story. The 19” rack as we know it was developed about 100 years ago, according to the well- written Wikipedia article ‘ 19 inch rack’. While Wikipedia postings are not necessarily definitive or always completely accurate, they are often a useful starting point: this one references a 1922 article, ‘ Telephone Equipment for Long Cable Circuits’ from the venerable Bell System Technology Journal
which has been scanned and is available at the Internet Archive, so you can see the rational and specifics of rack development from the primary source. Note that in the first half of the 20th century, the market position and technical expertise of the Bell Telephone System with respect to design, manufacturing, research, and installation was so dominant that they could set de facto industry standards, and often did. If your initial acquisition of instrumentation and equipment did not include a rack-mount kit, it is still worth consideration as your project moves ahead. Even a basic small form factor power supply unit (PSU) can migrate from the benchtop to a nearby rack. For example, the XP Power PLS600 series of benchtop PSUs can be easily put into a rack using the vendor-supplied PLS600 Rack- Mount Kit which supports mounting of two of these PSUs side-by-side (Figure 7).
trying to find and fix a bug within an inefficient and misleading benchtop arrangement or finding out that the problem was in the test set-up and not the prototype. To make it clear: an organized workbench is your partner, and a low-tech rack can help make that happen.
Reference
The solution was simple. One of our team’s engineers had a military surplus radio toggle-switch array about 7” wide and 2 ½ in. high (Figure 6). We used these switches (which had the smoothest toggling action I have ever encountered) to allow the software engineer to easily initiate a limit-switch event while sitting at the keyboard, and the set-up worked well. However, as the project proceeded, there were more instruments, leads, power supplies, and fixtures on the bench. Soon that set of toggle switches was hard to find Figure 5: Even a modest 11-inch-high rack placed directly on the corner of the workbench will help clear the clutter and encourage discipline. Image source: Hammond Manufacturing
1. Mercury News, ‘Jim Williams’ workbench captures his life and Silicon Valley’ www.mercurynews. com/2011/11/17/cassidy-jim- williams-workbench-captures- his-life-and-silicon-valley
Figure 8: This quote attributed to Albert Einstein does not necessarily also apply to product design, development, and debug. Image source: Quora
Don’t let Einstein’s wit compromise your productivity
You may have seen the ‘clever’ saying attributed to Albert Einstein on a poster similar to the one shown in Figure 8. Maybe that’s the situation for advanced physics, but for hands- on engineers at the bench, it’s not. This is made very clear in the excellent book ‘Debugging: The 9 Indispensable Rules of Finding Even the Most Elusive Software and Hardware Problems’ (Figure 9). In this indispensable work, author David J. Agans details the many benefits of having an organized work area with clear documentation, so you know what you have to work with and what you have done. It only takes one bad experience of wasting hours, days, or weeks
Figure 4: A single-frame full-height rack can also clear the test bench while offering easy access to front and back sides of the mounted
Figure 7: The XP
Figure 9: Debugging is among the most difficult engineering skills to master, and this book is a very insightful resource into strategies and tactics for hardware and software debugging. Image source: Amazon
Power PLS600 Rack Mount Kit eases installation of a single PLS600 unit or a side- by-side pair in a standard chassis equipment rack. Image source: XP Power
units. Image source: Bud Industries
Figure 6: This array of military surplus toggle switches was used to simulate the action of limit switches on a load frame during an ongoing product development process. Image source: Bill Schweber
we get technical
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