Controls › Control Panels
Panel Design
Designing a panel that passes inspection and survives the field.
Written guides in this section
Full references, procedures, and diagnostic guides published under Panel Design.
UL 698A
Industrial control panels for hazardous locations: what UL 698A adds to UL 508A, a panel in a classified area or a safe-area panel with intrinsically safe circuits, barriers and isolators, the control drawing, and where utilities meet classified areas.
8 min readUpdated Sep 5, 2026
NFPA 70 and the Control Panel
The National Electrical Code inside an industrial control panel: Article 409 and the listing it points to, the short-circuit current rating, overcurrent protection for control circuits, grounding and bonding, working space, and what an inspector asks.
9 min readUpdated Sep 5, 2026
Short-Circuit Current Rating (SCCR)
What a control panel’s short-circuit current rating means, how it is determined under UL 508A, why the NEC requires it on the label, and why the number is usually smaller than people expect.
9 min readUpdated Sep 5, 2026
Enclosure Selection
Choosing the box: NEMA and UL 50 type ratings, materials for corrosive and outdoor sites, sizing for heat and wire bending space, and the details at the conduit entries and the door that decide whether the rating survives installation.
8 min readUpdated Sep 5, 2026
Enclosure Heat Calculations
Estimating the temperature inside a control panel from the power its contents dissipate and the surface that carries it out, what to do when the answer is too hot, and why drives change everything.
8 min readUpdated Sep 5, 2026
Component Layout
Arranging a panel so it is safe to work in, cool enough to run, quiet enough for its signals, and possible to modify: power and control separation, heat, wireways, terminals, and the working space rules.
8 min readUpdated Sep 5, 2026
Topics in this area
UL 508A
The industrial control panel standard: what the listing covers and what the label requires.
UL 698A
Industrial control panels for hazardous locations.
NFPA 70
National Electrical Code requirements that reach into a control panel.
SCCR
Short-circuit current rating: how it is determined and why the label number is not optional.
Enclosure Selection
Enclosure Selection — practical reference notes for controls engineers, integrators, and technicians working with panel design.
Heat Calculations
Heat Calculations — practical reference notes for controls engineers, integrators, and technicians working with panel design.
Component Layout
Component Layout — practical reference notes for controls engineers, integrators, and technicians working with panel design.
Wireways
Wireways — practical reference notes for controls engineers, integrators, and technicians working with panel design.
Terminals
Terminals — practical reference notes for controls engineers, integrators, and technicians working with panel design.
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References to manufacturers, products, model numbers, software platforms, technical specifications, companies, standards organizations, or other organizations are provided for informational purposes and do not imply sponsorship, endorsement, authorization, or affiliation unless expressly stated. Manufacturer specifications must be independently verified against current manufacturer documentation.