MAKING THE MOST OF SAFETY BENEFITS
27 September 2012
Since the beginning of this year machine operators and manufacturers have been required to comply with the new Machine Safety Directive. Paul Considine of Wieland Electric explains how to gain maximum benefits from it
While the new Machine Safety Directive has only recently come into full force there has been a transition period for some time that enabled people to choose between the old and new Directives. During this time a number of machine operators and manufacturers opted for compliance with the new Directive and their experience shows there are a number of benefits to be gained.
The primary benefit, of course, is improved safety. The reality is that the old EN 954-1 was too simple to handle the programmable electronics that are used in modern safety systems. In contrast the standards underlying the new Directive – EN ISO 13849-1 or EN (IEC) 62061 – were designed with modern technologies in mind.
In parallel, EN ISO 13849-1 also facilitates the wider use of programmable safety relays. This, in turn, enables greater modularity to exploit the functionality of these newer processing technologies. All of which results in reduced costs, not least because the price of programmable safety relays has fallen significantly in recent years.
For example, as a general rule of thumb, a system using 3 to 4 standalone safety relays can be replaced by a programmable system for about the same cost. With more extensive systems the savings will be even greater.
Plus, there are additional benefits to using programmable safety relays, such as the ability to use a flexible logic editor to test the safety relays in the software before any installation work begins. This makes it quick and simple to spot potential problems and eliminate them at the design stage. As a result, much less time is spent in onsite testing, reconfiguration and retesting, compared to dealing with standalone relays.
In our experience, when equipped with these tools, electrical engineers are more inclined to try out different solutions to arrive at the best solution, because they can save the original settings and quickly restore the system if something doesn’t work out. There are also potential savings in installation times because while standalone relays require feedback loops and interconnecting terminals, programmable safety relays are wired back to a central I/O point. There are also fewer sub-systems overall, keeping the whole system simpler and less prone to faults.
Other time-savings result from faster commissioning, as the software highlights any errors and any adjustments that are made during commissioning can be reversed through the software if they don’t work.
The software also incorporates a full reporting structure linked to the technical file, so that all information is recorded without manual intervention and reports can be generated very quickly. Feedback from users indicates this ease of reporting has helped them to understand their maintenance patterns in greater depth and utilise their resources more effectively as a result. Beyond the design, installation and commissioning phases, there are ongoing benefits through the life of the machinery. These include easier and faster fault tracing and fixing, so that downtime is reduced and less money is spent on costly specialist engineers. In fact, very often, once the fault has been identified it can often be put right without any specialist input over and above that of inhouse engineers.
The result of all of these features is that machine owners and operators that take advantage of these new technologies can reduce their overheads and achieve a fast return on investment. So while new regulations can often seem like a nuisance, in this case at least the new Machine Safety Directive can be a positive boon when approached in the right way. And there is a lot of sense in teaming up with a company that has the knowledge to ensure you maximise those benefits.
- Opting for compliance with new Directives has a number of benefits
- Programmable safety relays offer the ability to use a flexible logic editor to test the safety relays in the software before any installation work begins