If you’ve been in industrial automation for a while, you know how challenging it is to keep up with changing safety standards. The recent updates to UL 60947-5-5, the standard governing emergency stop (E-stop) devices for industrial control panels, introduce new compliance requirements. In this post, I’ll outline the changes, what they mean for your operations, and how to help ensure compliance.
Understanding the latest UL compliance updates
Today, many older e-stop devices, including widely used models, no longer meet the updated UL 60947-5-5 standard. While these devices may appear fine externally, their internal mechanisms often fail to meet the new requirements. For customers, it’s time to evaluate the safety devices in your machine designs and ensure all E-stop devices are up to date to mitigate compliance risks, including:
- Normally closed (NC) contacts must open with specific actuator latching mechanisms (For example, the optional trigger action).
- The E-stop device must include a proper self-holding function (no auto-reset allowed).
- As before, E-stop buttons must be red and mushroom-shaped, but appearance alone isn’t enough–internal mechanisms must be updated.
Legacy systems installed before the UL standard update often do not meet the new requirements. Compliance consultants and UL inspectors have consistently highlighted this deviation, which is creating significant challenges for the industry. Today’s machine and panel builders must have UL-compliant E-stop devices in new machine or panel designs.
A modern E-stop solution to streamline safety compliance
To meet UL 60947-5-5 requirements, Schneider Electric has carefully evaluated our existing line of E-stop buttons. After collecting feedback from installers and maintenance teams, we designed the new KR18 series E-stop device to streamline product selection and reduce time-consuming installation.
The most interesting aspect? The devices actually reduced modularity. Sounds counterintuitive, right? But let me illustrate the logic.
Comparing Old vs. New Approaches
| Feature | New E-Stops | Legacy E-Stops |
| Modularity | Semi-modular with pre-assembled components | No longer UL-compliant for e-stop applications |
| Product Selection | Simplified: 12 main references plus five accessories | Complex: 113 different references |
| Installation Time | 20 seconds – quick clip system | 1 to 5+ minutes – depending on the contact block combination |
| Installation Risk | Minimized – Factory pre-assembled contact blocks | Heightened – Potential for non-compliant component mixing |
| Use Case Coverage | 98% plus of typical applications | 99.9% of potential applications |
| Technical Specifications | Full UL 60947-5-5 compliance | No longer UL compliant for e-stop applications |
The semi-modular design essentially does three things:
- Simplifies product selection. Customers want a compliant E-stop solution without having to wade through endless options.
- Speeds installation. In time-sensitive projects – which nearly all of them are these days – saving 40 seconds per e-stop adds up quickly when installing dozens of them across your facility.
- Helps ensure compliance. Fewer device options translate to a portfolio of key components carefully designed to help ensure compliance with requirements, reducing the possibility of field modifications that could lead to non-compliance.
Yes, you’ll lose about 2% of the ultra-specialized configurations, but in my experience, those edge cases are rare.
Take action
If you’re a machine manufacturer or panel builder with legacy E-stop installations, I suggest:
- Conducting a quick audit of your current E-stop units and compare them against the requirements of the last revision of UL 60947-5-5.
- Creating a prioritized replacement schedule for non-compliant units.
- Evaluating how semi-modular E-stops can enhance installation efficiency and streamline operations.
While no facility team enjoys spending money on compliance updates, there is a silver lining: the new installation process is noticeably faster than the old one, which may offset some of the upgrade costs through labor savings. To learn more, visit our E-Stop Push Button solutions page.
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