Engineering Articles
Longer-form technical writing, published as it is finished and revised as field experience corrects it. Every entry carries its published and updated dates.
5 entries
UL 508A Industrial Control Panels
What the listing actually covers, what has to appear on the label, and the requirements that most often cause a panel to fail inspection.
9 min readUpdated Aug 25, 2026
ISA-18.2 Alarm Management
The lifecycle standard for alarm systems, the rate targets that define a workable system, and why alarm rationalization is the step nobody wants to fund.
10 min readUpdated Aug 15, 2026
How to Size a Control Panel Power Supply
Add up the real load, account for inrush and simultaneity, add headroom, and check the heat you just added to the enclosure.
7 min readUpdated Aug 14, 2026
High Performance HMI Design
Grey backgrounds, reserved color, and displays designed to make abnormal conditions obvious rather than to look impressive in a demo.
8 min readUpdated Jul 24, 2026
Interlocks and Permissives
A permissive lets you start. An interlock stops you. Confusing the two produces equipment that either will not run or will not protect itself.
7 min readUpdated Jun 27, 2026
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Content on this site is general technical reference information. It is not engineering advice for a specific installation. Always follow the applicable codes, standards, manufacturer documentation, and your own site safety procedures. Verify against the equipment in front of you before you act.