Machine safety applications have evolved from physical safeguards to today’s wireless, remote control technologies. While protecting the workforce is the number one objective of a machine safety solution, wireless systems offer additional benefits and savings opportunities.
- Improved operator mobility and efficiency
Wireless systems allow operators to control and monitor an application without being in close proximity. An example would be a crane or hoist used to transport heavy equipment in a factory. With a range of up to 50 meters, an operator can work efficiently from a safe distance.
- Reduced installation time and improved maintenance
In a wired controls situation, the cabling of the control station accounts for 15% of the installation cost. Since material costs continue to increase, installers need to carefully consider the environment of the application, especially where cabling could be damaged. The replacement time and maintenance of such cabling can result in machinery being down for prolonged periods of time. With a wireless remote control system, the installation and commissioning time is significantly reduced.
- Enhanced diagnostics
Maintaining and monitoring applications is key to ensuring operator safety. With the remote device display of wireless control systems, operators can easily view machine diagnostics, which improves the maintenance process. For instance, users can set system parameters and alarms, and the system will notify them with a warning that indicates the cause of the machine stop. Additionally, it is possible to define the protection limits to the system to authorize machine movement under specific conditions. This helps to ensure the safety of factory floor personnel and to prevent damage to an installation.
- Functional safety
The evolution from electromechanical to electronic safety, and the increasing levels of functionality that result, require safety solutions that integrate intelligence to monitor and control unintended movements of a machine or unexpected changes to a process. This includes addressing the issue of operational stops, whereby the stop control does not remove power supply to the actuators. The motion function must be monitored in order to prevent unintended movements of a machine when the operator releases the push button for motion.
The increasing use of mobile wireless controls and variable speed drives requires monitoring of all related functions of the machine (Category 2 according to EN ISO 13849-1), not only for stop functions, but also for motion functions. This is already required in the current European Machine Directive 2006/42/CE.
The more advanced wireless remote control systems integrate monitoring of the stop function (up to Performance level e and Category 4 according to EN ISO 13849-1) and motion function (Performance level c and Category 2 according to EN ISO 13849-1) without the need for additional safety devices.
The use of wireless remote control systems in critical safety applications, which integrate emergency stop functionality, will increase in applications where operator mobility is beneficial to both safety and productivity.
Safety must remain the primary reason for adopting wireless remote control systems. However, OEMs and end users should also consider factors such as reduced installation time and costs, improved operator mobility, and increased insight for preventive maintenance. Combined, these factors offer significant competitive advantage over a wired solution.
For further discussion, you can read the white paper, “Wireless Technology – Changing the Face of Safety Applications,” or leave a comment below.