Electronics Engineering Magazine

Showing posts with label Industrial-Automation. Show all posts
Showing posts with label Industrial-Automation. Show all posts

Tuesday, February 02, 2016

Tacho Counter for Speed and Quantity Measurement

This was a Custom Built Product for Converting a 10-100 V Signal from a Motor Tacho to pulses, to indicate the distance moved by Conveyor belt with Job Material. The Digital Indicator would indicate the speed and the Mechanical Counter would Log Quantity of Materials Moved.

Process Control Instrumentation

Tacho Counter

The voltage was first brought down to low levels with an attenuator and zener protection. A VCO and a monostable created a train of pulses. These pulses drive a darlington transistor pair which operates the Electromechanical Counter that has a Solenoid. The voltage is also scaled, calibrated and displayed on a Digital Voltmeter.

Monday, January 04, 2016

PLC based PID Controller

Below is a Electrical Control Panel, It has a Strip Chart Recorder which is electro-mechanical, It has a PLC Inside. A handheld PLC Programming unit. The computer is showing the Ladder Logic Program. PLC is based on a embedded uC. The DIN Controllers are Analog + Digital circuits. So you see it is a Electrical Control Panel with Electronics and the PLC Ladder Logic means, Software too.

Process Control Application Notes

This is a PID Controller based Control Panel using a PLC from GE Fanuc Automation. The Computer is a 386 40MHz with 40MB HDD.

PID Controller PLC

Electrical Control Panel Wiring

Monday, February 09, 2015

Electrical Control Panel Wiring

Just like rackmounts hold big instruments or computers, control panels small or big have to hold DIN Instruments, switches and annunciators to make it easy for the operator. The maintenance work also is simple from the backside. It can be kept near the machinery which it controls.

Some Control panels go into Control Rooms at a distance away or at a greater height from the shop floor. This way they can monitor and give instructions while managing a larger process like processing of chemicals and at the same time safeguarding the instrumentation and computers with controlled environments.

Electrical Control Panel Wiring

Some of the pdf circuits are not easy to read, some have errors, this is mainly due to the importing of schematics from an older ORCAD Dos Version. I have corrected some circuits, some are to be checked. Also some circuits were not corrected after they were drawn by New Learners, as i wanted them to document what they learnt and familiarize with computers, Some did a good job. This section has no electronic parts, so you can figure out the diagrams.

Some example circuits of panels here Electrical Control Panel Wiring

Anantha Narayan

Monday, December 15, 2014

Closed Loop Control Systems

A Closed Loop Control System is the most important aspect of Maintenance, Regulation and Stability in any Live Process. Nature itself is self regulated in an intricate fashion, a keen observer can notice the subtle controls. In Human Created Industrial systems we have Process control as a complex science. We can start by understanding a Simple One.

Process Control Application Notes

When you fill a Bucket with water, You keep an eye on the Level of water, as you open the Analog Tap, which is an equivalent of a Motor operated Valve. Your Eye is an advanced Optical Sensor, which is able to sense the level by the computation in the brain, which in turn operates the muscles of your hand, thru the nervous system. The hand along with the Water Tap is is the Actuator. As the water fills up close to the top, you start reduction of the water flow and keep observing, then as it tops up, you tweak the tap to a trickle. When it reaches the limit you shut off the tap.

Closed Loop Control Systems

While you are half way filling the bucket, what happens if you take a short nap, or a friend comes by and you are get absorbed in conversation, the water overflows and goes waste. Then someone raises an alarm after the Runaway process happens. This is of minor consequence, but it is not so in the case of Temperature, Pressure and also many common systems like the driving of an Automobile. Remember the gears, brakes, accelerator to control and steer the car to the correct destination, a Runaway Process causes an accident.

    Wednesday, May 14, 2014

    Basic Electrical Circuits

    Electrical Engineering encompasses Everything in Electronics. Communications, Computers etc. are further specializations of Electronics. So it is best to Identify Electrical Circuits with Electrical Designs which excludes Active Devices. It can include Electronic Products in the form of wireable modules.
    So House and Factory wiring, Appliances like Ovens, Toasters, Power Generation and management; all these are electrical. Motors, Generators, Connectors, Relays, Contacters and Circuit Breakers are Electrical Components.

    See a diagram i made for a Sequential Process Control Unit, custom built for Vacuum Impregnation;

    Sequential Process Control - Vacuum Impregnation

    A Radio or Power Inverter is Electronic. When an Inverter or Electronic AC-DC Motor Drive is used in a Control panel or Power Supply system, that integration is shown as an Electrical Circuit. I feel Simple Consumer Electronic Circuits using Diodes, Transistors, SCR, Capacitors and Resistors can also be taken under electrical circuits; when they are used in Mains-Power or Household Appliances. Solar Energy related circuits also can be studied under Electrical Power Circuits.

    In Electronics RF-Microwave and Communications is a specialization area, Computer Hardware, Software, Internet form another major domain. Networking and Wireless data communication overlaps both the above.

    Power Electronics and Instrumentation are fundamental domains needed for many. Industrial Automation with Process Control Instrumentation is unique, but is supported by the fundamental domains. Many more finer areas like Robotics and Medical Electronics have a much sharper focus.

    Basic Electrical Circuits - delabs

    Anantha Narayan

    Thursday, May 13, 2010

    Industrial Control Panels and Instruments

    Instruction Manuals of Process Control Instruments and Industrial Automation Solutions, Control Panel Diagrams, Wiring, and Facia.

    Temperature and Pressure Controllers form a large part of Process control Instrumentation. Then you have Flow, Humidity and many more custom parameters.

    All Real Life Physical Phenomena are reduced to Analog Numbers by Sensors and Transducers. This analog value is amplified and linearized and brought into standardized windows like 1-5 Volts or 4-20mA and more.

    Industrial Control Panels and Instruments

    These Analog Values go to Analog Closed Loop Controllers or Meters for Measurement and Control. In Embedded Controllers, the Analog is converted to Digital ( At least 12 bit, 8 bits are cheap not used for industrial automation, more than 16 bits is not required as sensor accuracy/linearity never transgress such precision )

    Embedded Process Controllers may use Microcontrollers with Floating Point Arithmetic, Lookup Table, Logic and Basic Math. Advanced Controllers may use DSP and Complex Algorithms for Adaptive control. (self learn, fuzzy logic.).


    There is a instruction sheet for a 3 wire transmitter. It Amplifies the uV signals from a K type Thermocouple, Chromel-Alumel. The output is a strong 4-20mA which is fit for looping and driving a Controller an Alarm and an Analog Recorder too.

    8 Bits D/A may be used when a control signal is needed, like 4-20 mA Control Output driving a Thyristor PWM bank. Here 8 Bit is enough when the thyristor bank drives large heaters. The thermal inertia and delay makes very precise control nearly impossible.


    When a parameter needs to be controlled in a tiny area, precision control is possible. A 16 Bit control signal is required. The system/thermal design here is more important than the controller, they have to be tandem for obtaining repeatable precision control.

    Read More abou this here - Electronics Theory - Industrial Control Panels