CONFIRMATION OF AUTOMATION STRATEGY AND SPECIFICATION

CONTROL LOGIC'S:The first programmable controllers were developed 1970 ,by plant engineers and technician in response to a demand for a solid state system that had the flexibility of a computer,yet easier to program and maintained.These early programmable controller took up, less space than the relays,counter timers and other control components they played and offered much flexibility in terms of their programming and capability.The initial programming language was keyed to industry acceptance of the programming controllers, which was based on the ladder diagram and electrical symbols commonly used by electricians..Fixed programmable controllers as self contain unit with a processor,power supply, and a predetermined number of discrete and or analog inputs and outputs (I and O).
A fixed programmable controller may have separate interconnected components for expansion and is small inexpensive and simple to install,(2) Modular controllers are more flexible, offering option for I and O capacity processor memory size input voltage and communication type.
Originally programmable controllers are used to control application where I and O are digital.they were ideal for application that were more sequential and discrete than continuous in nature. Over times,suppliers added analogue and process control capabilities making the programmable controller a more viable solution for batch and process applications (Andreas, 2004).

It was not until micro controllers were introduced, that the programmable could economically meet the demands of smaller machines, i.e equipment that once relied exclusively on relay and single board computers ( SBCs ) micro computers are generally designed to handle 10,32, I and O in a cost efficient package making then a viable and reliable replacement .in addition this low cost and fixed  I and O option has opened the door for many smaller machines original manufacturer (OEMs) to apply automated control in places where it was not feasible in the past For example maintenance could used a micro programmable controllers to power compressor, pump, engine,travelling block, hoist machines,and air conditioner etc,While the technology like the programmable controller has been in the market for more than 25years,there is also the possibility for adequate advancement in this area of technology. There has been also a positive step for the development of Soft control program as an heir to the programmable controller,In essence the soft controller is the act of replacing the traditional controllers with software that allow user to perform programmable controller function in a personnel computer (PC) ..
It is easy band simple to put  the programmable controller in PC clothing, the soft controller is an important development for individual who have control application with a high degree of performance and processing content (somogyl, 2004).
Soft control however is only part of a larger trend of that of PC based control, the PC based control is a concept of applying control functions normally embedded in hardware or software to the control platform. These encompasses not just the control engine,but all aspect of the system including the programming operator interface,operating systems, communication application programming interface (APIs).networking and I and O personal computer (PC) based control.
The soft control system has been adopted by some manufacturer, but must continue to rely on the more rugged programmable controller .This may be true and achievable as new generation programmable controllers incorporating features of PC based control but maintaining their routs in reliability and ruggedness,(Bryan,1997).