Panic buttons or emergency stop switches are extremely important for protecting workers, machinery, and products from catastrophic failures. Traditionally, manufacturers include them with their machinery, and most are hard-wired. However, things are changing and now, these red emergency switches are finally going wireless.
When a machine malfunctions, or a critical incident occurs, operators often have to press these last resort switches to bring the system or the entire machine to a halt quickly and safely. Hence, these switches are aptly called E-stop, emergency, or panic switches. Operating these switches brings the machine or the system to a halt and prevents serious damage to products or the machine itself, as well as preventing injury to workers.
The importance of the emergency stop button is evident from a report from OSHA or Occupational Safety and Health Organization. According to this report, more than 5000 US workers were injured fatally in 2015 in industrial accidents.
Ever since the second industrial revolution, manufacturers have hard-wired E-stops in their machines as a standard solution to shut them down in case of emergency. Usually, manufacturers placed these emergency switches well apart from the usual on/off and other switches the machines normally carry on their control panels, making it easier for the operator to identify and hit them to stop the machine. With the E-switches being functionally so important, it is understandable manufacturers were reluctant to make them wireless. However, a wireless E-stop device would allow the worker to shut the machine down without even having to go near it, improving the safety factor.
The tech company, Laird PLC, of London, has seemingly realized the additional benefit of a wireless E-stop button, and has evolved the Safe-E-Stop. It is possible to incorporate the Safe-E-Stop with the existing hard-wired emergency stop system already involved with production systems such as assembly lines. This improves the on-the-job safety, as an individual operator or a group can immediately shut down a machine in the production line, without having to hit the hard-wired E-stop button physically.
The emergency might involve the closest machine-mounted E-stop button in the same danger zone. Therefore, the operator rushing in to operate such an emergency button could face a hazard and increase the response time for arresting the emergency.
Laird PLC has developed a wireless personal safety solution rated at SIL 3 as an answer to the above problem. The Rockwell Automation distributors market the Safe-E-Stop from Laird making it available through the Encompass partner program of Rockwell Automation.
Users can have continuous status indication on LED and LED readouts on the Safe-E-Stop system. They can use the IP/Ethernet port on the MSD or Machine Safety Device for reporting the status of the wireless E-stops actuated to personnel in charge of operations. It is possible to link as many as five PSDs or Personal Safety Devices to the MSD simultaneously. This allows multiple operators to collaborate or work independently to supervise the operation. Activation of an E-stop on any linked PSD causes the MSD to issue a stop command and notify all other PSDs immediately of the stop condition.