Who is the control system expert – customer or manufacturer?
With modern systems having so much functionality and requiring specialist knowledge David Clough, UK sales manager of Yokogawa, asks who is the expert these days? The customer knows what he wants to achieve but maybe not the most efficient way.Today, control systems are so feature rich it is almost impossible to make use of all the functionality available. The challenge then is how to make the most of a modern system and obtain maximum benefit without spending significant amounts of time and cost evaluating and potentially configuring every feature embedded in the system.
Often the basic purpose of a system is compromised by the desire to use the “free features” to best advantage. Once the system is designed, installed and commissioning is under way, one of the fundamental requirements is to tune the control loops to provide stable and reliable control of the process variables. Often this proves a challenge without the use of additional tools to speed up the optimisation of the PID settings, however if this is not implemented well the overall process performance will certainly be compromised. The multiple alarm and event choices for control loops and monitoring points then must be configured to provide a realistic level of operator alerts consistent with safe operation of the process. The alarm and event philosophy determined by the designer is critical to ensuring the appropriate level of alarms, as well as their priorities, are published to the operators under all circumstances. Too many alarms are just as dangerous as too few. We then should consider trends, graphic display design, reports, operator logs, historian, advanced applications – the list goes on.
No surprise then that the organisation best positioned to advise and help configure the system to meet the user’s needs should be the manufacturer of the system, after all the manufacturer designed the product to solve these problems. It is a fact that a system supplier will engineer and supply more systems than a user will ever buy – so who is the expert? I propose the customer should define what he wants from a system and the manufacturer should design, engineer and provide the system to meet the agreed definition – we could argue the expertise is slightly different but ideally collaborative.
Services to provide the important commissioning and configuration of the operational system are often squeezed into the last period of the project when time is short and pressure to become operational is at its strongest. Little wonder then that the system basics are not always left in an ideal state at project handover and significant scope for improvement is available. This usually leaves the operational team with the challenge and the need for expertise from the manufacturer is at its greatest. Fortunately this need is recognised and has led to a comprehensive set of services and capabilities available from the systems suppliers to be able to deal with this requirement. This need also continues over time as process modifications are made then resultant system modifications require to be implemented, loops re-tuned etc.
If you combine this with the requirement to support an operational system, routine maintenance tasks, updates and upgrades, system health monitoring and diagnostic fault management, the challenge should not be underestimated.
With many manufacturing plants reducing headcount in the drive for economic improvement and resultant expertise being lost it is even more important to ensure your system supplier has the capability and expertise to provide you with the necessary support you require to maintain a high performing, safe and reliable system controlling your process. The successful integration of these services into the operational philosophy of the facility is becoming more and more cost effective for customers due to the high cost of training people, required equipment and spares associated with every unique system installed.
So who is the system expert – customer or manufacturer, I leave you to decide?