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It is for this exact reason that emergency stop switches, commonly referred to as E-stops, exist.
According to current regulations, an emergency stop function is initiated by a single human action and is intended to avert or reduce arising hazards to persons, machinery or work in progress. Despite being such a widespread feature on industrial equipment, not all E-stop buttons are the same and their design is continually evolving to remain compliant with new regulations and ensure a reliable response. The most recent update, DIN EN ISO 13850, was introduced in 2015. However, many companies, including some major UK organisations, are still not up to date and use buttons that are no longer in keeping with regulations.
Staying abreast of new developments is vital, because although E-stop design isn’t about being revolutionary, keeping up with machine technology and having protective measures that respond to evolving safety needs will ultimately lead to greater protection in the event of a hazard.
For some companies, such as EAO AG, a leading switch manufacturer, keeping up with changes in safety legislation and trends in switch usage is a priority. EAO produces certified Emergency Stop switches suitable for nearly every application.
Used on a range of applications, including factory conveyor belts, escalators and control panels, the series 45 Emergency Stop switches are suited for harsh industrial environments. These 22mm mounted IP69K rated E-stops are resistant to impact, vibration and shock and are rated for 300,000 switching cycles.
The series 61 compact 16mm mounted emergency stop switch is a low back panel depth IP69K sealed switch – ideal for use in space critical applications.
The series 84 E-Stops, developed for hand-held enclosures with a back panel depth of only 13.5mm and a low front profile, are ideal for machinery and factory automation applications.
Ultimately, the responsibility of knowing whether an emergency stop switch is in keeping with all regulations and is up to date with technological developments as required, falls to the designer and the installer of the equipment.
How does it work?
With E-Stop buttons, an advanced switch design allows for the foolproof opening of the electrical contacts of machinery through a latching-in mechanism. This way, the stop command overrides the sustaining function and stalls the equipment’s operations. To close the electrical contacts and thereby restart the machine once a hazard has been cleared, assessed or averted, the actuator will need to be manually unlatched with a twist or key release.
The design of the E-Stop switch depends largely on its intended application and is not a one-size-fits-all device. EAO manufacture emergency stop buttons for a wide range of industries, including machinery, factory automation, transportation and many more.
Evaluate the risks
It may come as a surprise, but an E-stop mechanism is not always required by law. In fact, in some scenarios, an emergency stop function can create additional hazards and be a barrier to averting or reducing any present risk. If a hazard or danger can be more effectively controlled in the absence of an emergency stop button, it shouldn’t be included or added to the machine.
The only failsafe way to determine whether you need an emergency stop function on your machinery or equipment is through a full risk assessment, which is thankfully a basic requirement in most places nowadays. Many vendors, including EAO, offer bespoke services to their customers, making sure that the design, engineering, production and integration of E-stop switches are suitable for their environment and equipment.
What should I know?
The ergonomics, electrics, mechanics and general design of E-stops are tightly and specifically regulated, with good reason. Although relatively straightforward in purpose, the technology behind them needs to be failsafe and their appearance must be uniform so that they are easy to locate and use in the event of a hazard.
Generally, European emergency stop pushbuttons are mushroom-shaped, or an inverted cone with a rounded top, and according to all current regulation, must be coloured red. Any background that is in place behind the main switch should be coloured yellow for maximum visibility if possible. According to ISO 13850, any arrows marking the device as an E-stop should also be red. Any text or symbols should be printed on the yellow background for best visibility and to minimise wear over time.
E-Stop technology design isn’t about constantly generating new models, but about creating mechanisms that are reliable and robust even in the most extreme environment. As well as steady, rugged and fully compliant pushbuttons, EAO provides all the accessories required to complete almost any E-Stop application, including special enclosures, switch guards, palm guards, custom labelling and more.
Don’t take any risks with your emergency stopping mechanism. If you’re not in compliance with all relevant regulation, you could be putting people, machinery and work in harm’s way.
As an official and authorised UK distributor of EAO products, Dalroad supply a full range of EAO switches including E-stops.
For more information, please visit www.dalroad.com
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