The Engineering staff at Chinook has experience designing and installing control systems for many different industries in a full range of configurations.  They also have spent substantial time employed by a Fortune 500 Manufacturer performing automation services.  This daily exposure to not only the special needs and environment of manufacturing, but also the use and maintenance of their systems,  has evolved their designs far past simply performing the desired function.
What is a Control System and Why use Chinook?

Control Systems vary in size and complexity.  A simple system may just start a motor or turn on a warring light.  A large system could run an entire plant or integrate multiple sites.  Complex systems can coordinate multiple axis with robotic precision.  A general overview of control systems is given below with topics including Types   & Components
- No system is to large or small for the Chinook Team
Please see the "Services" page for  details
Any control system you have installed, regardless of integrator, will perform the required task once completed (time and money is spent until this is so).  The measure for quality of a system is found in the operating costs.  Beyond completing a task the system should be safe and easy to operate, maintain & troubleshoot.  In addition it should reduce downtime by self monitoring, operating through failures and assisting with troubleshooting. 
"Chinook has a unique perspective on Automation Design..."
"Their focus is on Long Term, Low Cost, Operation"
Chinook utilizes many design considerations that go beyond primary operation to greatly improve the operating costs of our systems.  The following criteria are implemented to the level desired by each client.
CONTROL  SYSTEMS
hinook
C.
Automation Engineering
Control Systems
PLC & PC Based
Motion Control
Down-Time Reduction
MMI Design
Control Panels
Safety System Audits
Area Safety
Machine Safety
Andon Systems
Real-Time Scheduling
Poka-Yoke
Line Data Tracking and Access
Visual Inspection
Wiring Testing
Pres./Abs. Verification
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Components of Control Systems - every system contains the following 5 components;

Inputs
These are status signals that give information about the machine or process.  Inputs are used to determine triggers for functions, interlock activity or monitor conditions.  There are countless types of input devices from simple switches to sensors (pressure, humidity etc.) and advanced video recognition.  Proper selection of inputs is critical to the performance and reliability of a control system.

Outputs
These devices perform the functions and intent of the control system.  Examples are motors, flow controls, actuators etc.  Any action performed by a machine or process is the result of an output.  Specifications for outputs rely on the type of function and the precisian or accuracy required.  A pneumatic cylinder and a ball screw both perform linear motion.  The cylinder is far less expensive but provides a sluggish response and poor positioning.  The ball screw can move an object with the exact required velocity and position to better than 1/1000 of an inch.

Control Hardware
Depending on the system the hardware may be simple wiring, electromechanical devices or a computer processor.  In all cases the hardware uses the inputs and control scheme to run the outputs and perform system functions.

Operator Interface
Any device that the operator uses to control or monitor a machine or system is considered an operator interface.  A small system may only have a pushbutton to initiate action.  A plant wide system would have multiple computer workstation interfaces for control, scheduling and monitoring. A database could log and report historical status from throughout the plant for use in quality control, lean promotion, warranty / legal and many other aspects of the company.

Integration of the above
Integration of all the components is the heart of a control system.  This is were the control schemes are designed that set the functions and response for all system hardware.  In addition to determining the operation, the integration is responsible for error checking, fault recovery and safety.  The mark of a good integration scheme is anticipation of problems and failure modes with sufficient design to identify and react to them.
Design for Operation Cost @ Chinook
Error Reduction
The majority of errors are preventable.  Most control systems allows them by omission.  The system does not check for the condition and therefor can not react.  Chinook specifically identifies potential error sources and solutions for prevention.  The client decides the level of protection included in a design.  Errors fall into the following categories;

  • Operator Errors - depending on the system many different means can be used to reduce errors from the human factor.  Most fall into a few categories. 
1.  Function Disable / Interlock
2.  Task or Setup Verification
3.  Status or Sequence Verification
4.  Function or Sequence Guidance
  • Machine or Process Errors - errors not created by an operator result from one of 2 conditions.
1.  Unanticipated State or Condition
2.  Unidentified Failures
Chinook Identifies conditions and Solutions
Design for Safety
Operator safety should always be a top priority and designed into a system from the onset to create seamless integration.  To often safety is added after start-up or injury.

  • Hazard Point Protection - Prevent injury at hazard points by guarding from, detecting or preventing human intervention.  Guards may be fixed or moving, and interlocked.  Detection must be done in time to shut down motion before exposure.  Prevention is often achieved through process.  Ex.  A press brake that will not lower with a part present and stops with just enough space to insert the part.  Once the part is inserted fingers will not fit in the pinch point and operation continues.
  • Hazardous Configuration Prevention - Identify all dangerous settings or  configurations due to failure or operator error.  Ensure that they are identified by the system to prevent injury.  Often sensors are required to determine failures and are not used in the standard operation of the machine or system.
  • Hazardous Sequence Prevention - Lock out all functions not intended for the current state.  To often this is left to common sense!  For automated sequences verify that previous steps were completed successfully.  Ensure that no single point of failure will result in injury.

Down-Time Reduction
Down-Time is the most costly aspect of running a machine due to the cascading affect from critical equipment.  The same approach used to prevent injuries can prevent Down-Time, inspection and redundancy.

  • Critical Failure Prevention - Inspect critical  functions and devices for early signs of failure.  Examples are comparing function times to a base line or detecting drive shaft imbalance.  The level of prevention should rise with the level of resulting damage from the failure.
  • Failure Bypass Operation - Provide backup functions to allow a machine to continue operating while a reported failure is scheduled for repair.  These may be as basic as a prox. switch or as involved as a backup hydraulic system.  We have seen a  $20 limit switch cost a company $600,000 in Down-Time
  • Restricted Operation - Not all failures can be prevented.  When they occur a limited set of functions may still be operational but most of the time are not available.  Restricted operation modes allow partial utilization of equipment under failure conditions.

Self-Diagnosing Controls
Low operating cost control systems have extensive self-diagnostics to Identify, React to and Report system faults and anomalies.

  • Failure Identification - Expected operation should continuously be compared to actual feedback.  When they differ, the failure should be isolated as much as possible with available information and reported efficiently to the operator.
  • Troubleshooting Routines - Provide isolated routines to run during a "Test" mode that aid in troubleshooting subsystems of the machine.

Design for Maintenance
  • Component Access - Design layouts so components are accessible for replacement and testing.  Open access to electrical connections for troubleshooting.
  • Troubleshooting points - The layout of the field wiring should be configured for easy troubleshooting access.  Terminal points should be provided so signals can be tested without disconnecting wiring.
  • Calibration Routines - Processes or sensors requiring calibration should have simple routines that are easy to follow and as automated as possible.
  • Maintenance Overrides - Provide functions to bypass system interlocks for maintenance functions like replacing mechanical components.

Operation Complexity
The operator interface and feedback for a system can be very costly if poorly designed. Systems that are complex to run require more training, are operated less efficiently  and reduce the flexibility of your work force.  Interfaces range from simple buttons and lights to PC based operator workstations.  In each case operation can be confusing if simply designed for function and not Use. 

Example :  Function design is making sure there are the correct number of buttons.
Use design organizes, labels and mechanically interlocks the buttons while providing lights to indicate available functions and operation sequence .

Even the most complex of systems can be configured to require little to no training while preventing operator induced errors and failures.
Types of Control Systems - they fall into the following categories;Top

Direct
These systems involve one action and reaction.  The result from the input is always the same.  The most common example is a switch that turns on a motor.  There may be many functions but if each one has an associated switch the system is direct control.

Relay Logic
To coordinate multiple actions with simple control schemes, relay logic is often used.  Relays, timers, counters and other electromechanical devices are wired in a circuit to produce the desired outcome.  To modify the functions of the system the components must be rewired.  Most relay logic systems are very small or consist of basic functions that are not anticipated to change.

PLC Based
When the control gets more complex or the system size increases a computer processor is used and the functions are programmed in software.  PLC (Programmable Logic Controller) systems are the most common but PC and Microchip based architectures are also utilized.  The software not only allows for intricate manipulation of a large number of devices but also the flexibility to modify the functionality with only programming modifications.

Motion Control
When very precise control of motion is required special hardware is used.  These motors and other components are run by a motion control system designed to interface with them.  Advancements in the recent years have blurred the lines as many PLC platforms can now perform limited motion control functions.  Advanced systems integrate video and motion.  Object recognition and analysis allows robots to identify parts, inspect tolerances and define positrons.  For example; parts placed on a conveyor belt in random locations and orientations may be inspected by a vision system and then picked up for packaging or rejection by robotic arms (guided by the vision system).

Supervisory Control
This definition refers to control system that runs multiple other control systems.  Typically they are in separate locations (buildings, cities etc.) and the supervisory system is used to monitor and define operating parameters.  General functions are manipulated and the individual local control systems perform the requested tasks.  This is like a boss directing workers.

Chinook provides engineering services for all these systems.
Chinook Automation Engineering LLC, Maple Valley, WA    WWW.ChinookAE.Com
Hazard Assessments
Control System - A means of creating a desired response from a machine or process.