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.

Process Control Application Notes

So you see it is a Electrical Control Panel with Electronics and the PLC Ladder Logic means, Software too.



Electrical Control Panel Wiring

This is a PID Controller based Control Panel using a PLC. The Computer is a 386 40MHz with 40MB HDD. The printer Epson dot matrix, The worktable is an inhouse design made of steel and plywood, capable of withstanding heavy loads.

You can also see a Stripchart recorder for the temperature logging and PID curve study. This controls a Steam Valve with 4-20mA output.   

Design Service and Custom Projects

Some old examples of open custom designs. these were made to educate the customer and also study the capability  of online communication and and collaboration tools for such activity.

Two Stage Sequential Timer Docs - 

The circuit is a two stage sequential timer with auto reset. It can turn a Solenoid On/Off after a Sequence of delays that are preset. This is also a basic example of timer usage in automation.

Design Documents

• Discussion of Sequential Timer - A
• Discussion of Sequential Timer - B
• Sequential Timer Specs.
• Two Stage Sequential Timer.
• Li-Ion Battery Charger.

All Timers are 1 - 30 Secs Analog with Presets to adjust with a screwdriver. The Switch, Solenoids and Power supply has to be via terminal blocks or plug-jacks. The PCB may be upto six Square Inches for standard DIP components but with SMD it may be smaller.



Four Channel Temperature Alarm Docs

The temperature in a pipe is monitored with four RTD Pt-100 Sensors, The type of probe could be Extruder RTD probes with Bayonet or Compression Fitting, Get it from Omega. To keep costs low you can choose small thin film RTD sensors, they will be fast but on rough usage may break.

Design Documents

• Discussion of four Channel Alarm.
• Four Channel Temperature Alarm.
• RTD Pt-100 Four Point Alarm.
• Timer and Counter Modules.

The time taken to measure the temperature at the 4 points will be less than 4 seconds. An optional display of the measured temperature as shown above can be avoided by using a DMM to adjust the setpoint.

The Analog Timer Module can be set from 0- 30 minutes. If out-a remains high even after set time a out-b alarm goes on to sound a buzzer and flash a LED light.

The Timeless Performer 555 Chip

The Incredible 555 : Here are some 555 circuits, The most versatile and simple chip of all time !

Some of my 555 Circuits are at my blog - 555-Circuits - delabs Schematics

The best part of the 555 is that it has an voltage detection. It has a Versatile Logic which is defined by voltage comparators. The ability to loop it like an opamp for feedback makes it the first "Programmable" Mixed Chip. In short it make an ideal building block.

555 The most Incredible Chip - At my Learning-Teaching Blog Solderman Basics.

Signetics made the 555, This is one IC that is like a E-LEGO, this along with Op-Amps and other components can make many interesting projects. On some pins like Control Voltage it responds to analog signals and on Reset and Output the signals are Digital like. The 7555 a CMOS version consumes lower power and oscillates at higher frequencies.

555 Timer Circuits at delabs



555 Timer based Circuits

• Pulse width modulation using 555.
• Fixed frequency variable duty cycle 555.
• 555 watchdog for uC and uP systems.
• OR gate with two 555.
• Drive SCR thyristor with 555.
• LM555 Voltage Doubler.
• 555 based Reset Generator.

delabs PDF Circuits

I am now Organizing and Updating my main product design sections. Many Useful Websites and Nice Firms have gone over the last few years. I had to update to remove many broken links and improve navigation. These parts of my websites partially represents my Test-Measurement and Instrumentation firm i ran for some years. It also contains many of my designs and circuit innovations from my early days.

2020 -  The HTML pages are now Responsive from Computer Tablets, Notebooks to Large Monitors. All sites are SSL means https: Private and Secure.

delabs PDF Circuits

In 1999 most of my circuits in the OrCad and PDF Formats were uploaded as zip files in free websites of Netscape and Tripod. Then i got suggestions, Feedback and Thank you letters from all round the world. Later some support, encouragement from enthusiasts and engineers in the US and Europe made me improve the Websites "CMS" and content organization. I am now updating my Plain old HTML Pages for the 4th time in 15 Years.



Some parts of delabs/dapj use the CMS Technologies of The LAMP Stack  that arrived later. The New Tech Blog areas link  many EE firms and Resources all over the world. The tech cladistics i developed and used to organize my content is intensive.

Please note these technical pages are for Electronic Enthusiasts and Engineers around the globe for Reference and to improve basic Design capabilities.

These pages or ideas of delabs technologies and dapj tech cannot be copied, replicated or used for content development online or offline print materials.

Instrumentation and Industrial Design

• Analog Circuits - OpAmp, Signal Condition, Mixed Signal.
• Digital Circuits - Logic, CMOS, Counters, Timers, 555.
• Power Electronics - SMPS, Regulated Supply, SSR.
• Microcontroller - 8051, 8052, OpCodes, Analog Interface.
• Test Measurement - Multi-Meters, Small Test Tools.
• Data Interface - Virtual Instrumentation, Device Networking.
• Custom Projects - Sequential Process Timers, Chargers.
• Hobby Projects - Insulation tester, LED Circuits, Meters.
• Theory Tutorials - Basic Electronics, Instrument Design.
• Electrical Diagrams - Control Panels, Reference Tables.
• Resources - Electronic Firms and Electronic Projects

EE Design Library

This is a curated list of EE Pages from delabs websites and blogs. It is an attempt to organize delabs created ee reference pages in one place.

Analog Product Design - Here are design aspects of circuits using Op-amps and Comparators. Discrete Semiconductor Circuit design like using Transistors and Diodes. RLC parts.

 Electronic Design  - Things related to Electronic Design in all its aspects. That includes the prototyping, mechanical, electrical and PCB. Product Safety, EMI-RFI, Reliability and Robustness.

Embedded Systems - This Section is related to Microcontrollers and Related Resources. Microcontroller, SOC, FPGA, ASIC. From 80C31 to the Latest  chips will be the scope of this section.

Power Electronics - The design of Power Supplies, DC to DC and AC to DC Convertors, SMPS, High Voltage and High Current equipment. Mosfets, Thyristor, Schottky Diodes, Ferrite Magnetics and Chokes are the various components used.

Components Materials  - Electronic Components and Engineering Materials. The parts, kits, tools that are used in designing and manufacturing electronic products. The Mechanical Nuts-Bolts and Raw Materials used in Electronic Manufacturing.

EE Design Library - Electronic Product Design Resource.

Measurement is everything, and an Oscilloscope is a EE Stethoscope.

delabs Technologies - Product Design - Industrial Automation and Instrumentation. delabs Technologies uses the brand names delabs and dapj in its Web Services and Resource Sites. These together form an Electronics Informatics and Product Design Technologies Web Consultatory.

Electronic and Instrumentation Tables

Tables, charts, quick reference cards, booklets and handbooks; are the most versatile tools of learning and putting the learning into applications. These should not have a lot of language or flowing text. These are - to the point, easy to remember, graphical, colorful (memory aid).



Just like a circuit diagram, flow chart or ladder logic can graphically interface with a human mind, Tables and Charts easily embed into ones memory.

Electronic Tables and Charts

• Exponents - Giga Tera Pico Nano
• Ohms Law - Amps Volts Watts Relation
• Types of Resistors - Color code
• Binary and Hexadecimal System
• Thermocouple and Pt-100 RTD
• High Resistance Insulation Materials
• Mains Voltage Power Transformers

MCS48 Code for 80C39 Microcontroller

80C39 is a Cmos Version of 8048 the one that preceded 8031-8051. MCS48 is the set for that, MCS51 is the current set.

Here is an example project for 80C39-8748-8749 microcontroller. This code was written by me, and it works. But the documentation is not complete or may have errors.

80C39-8749 MCS-48 Examples and code.

Process Controller code here 80C39 Code for MCS48. The circuit for these are on this page along with other circuits.

This may be difficult to put together now. But the code and hardware is near compatible to 8051 uC. Now there are may types of ADC and uC.

The circuit of the Analog Front End was a V-F Converter

This was supposed to have Analog in and Analog out. Some parts of the circuit may be in the 80C51 page. This has ramp-up and ramp-down settings for the Increment and Decrement buttons. This helps setting setpoint quickly. There is also debouncing for the pushbutton.

Electronic Engineering Resources

Sponsored EE Resources - This section is being added to financially support the delabs internet resources spanning many domains and blogs. Request a Sponsored listing here using the delabs Contact Form.

Sponsor or Donate - You can donate using PayPal to support the work of delabs and dapj. When you donate USD 100 and above you will be listed in the delabs page with your Website or Blog.



Your Company or Business also will get a free listing for Five Years as a Sponsor in our Electronics Resources Directory, in an appropriate category. This listing will also be mirrored at Electronics Resources. Request the Sponsored Listing using our Contact Mail form.

Some Electrical and Mechanical pages closely related to Electronic Manufacturing and Industrial Engineering will also be listed here. Each Subject page is also a Stub for listing and recording the specific subject related writing and posts of delabs in various other blogs and sites.

Categories of EE Websites of Firms and Resources

• Circuit Diagrams Archives Reference
• Embedded Microcontroller Resource
• EDA CAD Circuit Design Software Tools
• Electronic Engineering Magazines
• ASIC, SOC, CPLD, DSP and FPGA
• Electronics Resources and Tutorials
• Industrial Automation & Process Control
• Test & Measurement, Instrumentation
• Semiconductor and IC Application Notes
• Datasheets, Standards & Service Manuals
• Components Parts Kits and Materials
• Power Electronics & Solar Energy