A manufacturing company has recently installed a new paint line. The paint line $($see figure $1)$ can mix different colours of specialist paint to a set temperature. After the mixing process has been completed the tank will empty to fill a batch of tins. The completed batch will then be transferred to a labelling process before final transfer to a warehouse, ready to be shipped to the customer.

Task $-$ Your company has been contacted to tender for the control system for the paint mixing and packaging line. The project manager has decided to utilise your skillset and you have been tasked with individually designing a PLC program for the machine that as a minimum meets the basic system requirements. As part of the tender process, you must submit the appropriate documentation to an industrial standard, including sequential flow charts, machine drawings and PLC programs.

Note: Please note all work should be completed on an individual basis and you will need to carry out a face$-$to$-$face demonstration of your finished programme in order to complete the assessment.

Task $1-$ System Control,

The system shown in figure $1$ is to be controlled by the PLC$.$ The PLC will perform the following functions using the sequences and basic requirements listed below, Sequence $1($Paint A$)$ is heated to a temperature of $30$ degrees and mixed for a $2-$minute cycle. Sequence $2($Paint B$)$ is heated to a temperature of $60$ degrees and mixed for a $5-$minute cycle time.

$-$ Basic System Program Requirements $($to be used as guidance$),$

Step $1-$ Upon activation of the system ready push Button, the system will be made ready to use $-$ only if the conveyor, heating elements and mixing tanks are switched off. This will also be indicated by a red System ready light. The system must have an emergency stop to shut down the full system.

Note: Emergency stop should stop the full system from working until reset.

Step $2$ When the system ready light is on$,$ the process will start after a $10$ second delay when selected by the machine operator and the conveyor will then move the empty tins to the appropriate filling station.

Step $3$ Once the batch of tins is present at the filling stations and the low$-$level sensor is activated, the fill pumps are energised to allow the filling of tank A or B until the high$-$level sensor is activated.

Step $4-$ When the tanks are full, the mixing and heating cycle will start. After the mixing cycle is complete, there will be a delay for $5$ seconds to allow the paint to settle and then the tank will empty until low level sensor is activated and the batch is complete. Note You must ensure that if there is a loss of power the mixing cycle does not exceed the paint cycle time.

Step $5-$ Once the batch has been completed, energise conveyor motor and transfer to the warehouse process. Note: The number of batches must be counted in and out of the warehouse location and once $50$ batches have been made, the program will prevent the operator from making any more, until the system has been reset.

PLC Design Notes $(20$ Marks$)$

The customer has asked for a comprehensive a set of design notes for the PLC program based on the required functionality described above. This may include:

Flowchart or Sequential Function Chart

I$/$O list

Variable list

Comments on the purpose of each rung

Pneumatic$/$Hydraulic Drawings

PLC$/$HMI Program $(20$ Marks$)$

You will create your PLC program individually using your design notes. You can refer to the to the following documentation which is available through the CCW software and on Rockwell Automation website $($details in the lab guides$)$:

CCW programming manual

Micro$820$ hardware manual

CCW quick start guide

Actuator$/$Sensor Evaluation and Selection $(10$ Marks$)$

Based on your experience of developing the PLC Program consider how the machine could be improved, you may wish to consider performance, efficiency, reliability, or maintainability as part of your assessment. You should refer to the actuators and sensors which are used and choose at least $2$ actuators and sensors that could be used to improve the system, providing a description and evaluation of each type. You will present a brief $($max $4$ pages$)$ report which summarises the evaluation, supported by appropriate references to your earlier work and any relevant technical documentation. Can I please get a ladder diagram and a sequential functional chat.