If you've spent any time working with pushbutton stations, selector switches, or indicator lights, you've handled legend plates whether you knew them by that name or not. They're the small engraved tags that sit directly beneath or around a control device and tell the operator exactly what that button, switch, or light does.
Simple concept. But getting them right matters more than most people think - and it's why they're one of the most requested custom panel labels we produce.
What Is a Legend Plate?
A legend plate is a custom engraved identification tag designed to mount on or around an industrial control device. They're built to fit specific device mounting hole sizes and tell operators, maintenance personnel, and inspectors what a control does at a glance.
Common applications include:
- Pushbutton stations - identifying START, STOP, EMERGENCY STOP, JOG, RESET
- Selector switches - labeling positions like AUTO/MANUAL, ON/OFF, HAND/OFF/AUTO
- Indicator lights - identifying RUNNING, FAULT, POWER ON, READY
- Pilot devices - any control surface where operator clarity matters
In a busy industrial environment, a missing or illegible legend plate isn't just an inconvenience. It's a safety risk. An operator who can't immediately identify which button stops a machine in an emergency situation is in a dangerous position.
Standard Legend Plate Sizes
Legend plates are manufactured to fit standard device mounting hole sizes. The two most common are:
22mm Legend Plates - The most widely used size in industrial control panels. Compatible with devices from Eaton M22, Allen-Bradley 800F, Siemens 3SB3, and most other major manufacturers. Available in rectangular and bell-shape profiles.
30mm Legend Plates - Used with larger format control devices, including Allen-Bradley 800T series and equivalent devices from other manufacturers. Available in rectangular and bell-shape profiles. Less common than 22mm but standard in many older industrial facilities and heavy equipment applications.
If you're retrofitting or replacing legend plates on existing equipment, the device itself will tell you which size you need. The mounting hole diameter on the panel cutout is your guide.
When retrofitting or replacing legend plates, match the profile to what's already on the panel for a consistent look. If you're building new, Traditional is the safe default for most applications.
When Are Legend Plates Required?
OSHA 1910.217 and general machine guarding standards require that controls on industrial machinery be clearly identified. For facilities subject to OSHA inspection, unlabeled or illegibly labeled controls are a citable violation.
Beyond OSHA, NEC 110.22 requires that the purpose of disconnecting means be legibly marked. While legend plates on pushbutton stations aren't always covered by NEC directly, the underlying principle applies across electrical and industrial installations: operators need to know what controls do.
In practice, any time you're installing or retrofitting a control panel for an industrial client, legend plates on every pushbutton, selector, and indicator light should be considered standard scope, not an optional add-on.
Material Matters for Legend Plates
Industrial control panels live in tough environments. Legend plates face the same challenges as panel labels: machine oils, cleaning solvents, UV exposure in outdoor installations, and physical contact from operators using the controls hundreds of times a day.
Printed or vinyl legend plates degrade quickly under these conditions. Laser engraved panel labels and legend plates on two ply acrylic are the standard for industrial applications because the engraving is permanent. The text is cut into the material itself, not printed on the surface, so there's nothing to fade, peel, or wipe off.
At Panel Label Company, our legend plates are manufactured from UL approved Rowmark DurMark materials rated UL94-HB, the same material standard used across our electrical label line. Our 22mm and 30mm plates are available in rectangular and bell-shape profiles, with custom text, color combinations, and multi-language options.
OEM and Retrofit Applications
Legend plates come up in two main scenarios:
New panel builds. You're building a control panel from scratch and need legend plates spec'd and ordered before the panel ships. Our online designer makes it easy to configure exactly what you need with live preview and instant pricing.
Retrofit and replacement. Existing legend plates have faded, broken, or the panel has been modified and the labels no longer match the current configuration. This is extremely common in older facilities. We can match standard profiles and produce replacements with no minimum order, so you're not buying a box of 50 when you need 6.
How to Order Legend Plates
Our online designer at PanelLabel.com supports 22mm and 30mm legend plates in standard profiles. Select your size, profile, text, and color combination, get a live preview, and submit directly to our production queue. No quote required.
Most orders ship within 1-2 business days from our Clayton, NC facility. For large panel builds or OEM applications with custom requirements, contact us directly.
Design Your Legend Plates
Panel Label Company - custom laser engraved legend plates, electrical panel labels, and industrial nameplates. UL-approved Rowmark DurMark materials. Serving electricians, panel builders, and industrial contractors nationwide from Clayton, NC.