delabs Circuits

Thursday, July 31, 2008

Build your own Meters and Instruments

These are basic measuring circuits you can build for your home lab.

I have documented a lab DMM i had built for my use many years ago. the circuits may have errors, build it only if you understand.

Analog Dial AVO Amps-Volts-Ohms meter

This was designed, keeping in mind, that sometimes we have few components available and we could be flat broke. Even that you could not carry your DMM somewhere, but you have to make some instrument for a quick need with what is available. If you are out of cash or feel like Robinson Crusoe, then this is a low cost measurement system. I designed it to practice on eagle, i am not sure how this circuit may work, it is not tested . But i have built, repaired and designed many DMMs. So there is a fair chance, parts of it may work :~) - Low cost Dial AVO meter

Auto ranging 4-1/2 digit digital voltmeter using ICL7135 of Intersil.

Tuesday, July 01, 2008

Temperature Measurement and Control

These are documents and circuits which will help learn Basic Temperature closed loop control, There are many ways to control temperature.

  • ON-OFF Hysteresis or Dead Band Control.
  • Proportional Control with Reset.
  • Full PID Control, Manual and Auto Tune.

The first one is an electronic emulation of Thermostat or Electro-Mechanical Controls. The second is a Time-Proportional like a slow PWM. The third is the complete adaptive control.

While the first is like a limit switch, the second works like a SMPS, the third PID takes into account the speed of the process and dynamic changes or disturbances of the system and compensates in real time.

Example - In a Oven, one batch may have 100 metal boxes to heat, the second batch may have 10 boxes, the door may be frequently opened and the mains power (heater) may be fluctuating. A system that is able to adapt to these changes, without much readjustments is the objective of an ideal process control. The Accuracy and the Energy efficiency being the most important.

Process control Application notes

  • Temperature control in plastic injection molding
  • Cooling Temperature Control
  • Capacitor Temperature Monitor

Documents

Contents

Basic Electronics
Basics of Electronics
Product Production
Work Discipline
Testing Points
Learning Electronics
Electronics Theory

Production Notes
Prototype Fabrication
Electrical Circuits
Electromechanical


Library
Scots Guide Electronics
Engineering - Wikibooks
Design Lab - Jim Svoboda
DC Circuits UOG
Socratic Electronics
Blobz Guide Electric Circuits


Product Design
Product Development
Constant Current Source
Good Voltage Regulators
Insulation Resistance
Digital Insulation Tester
DN Schematic PCB 04
DN Product Design 07


Hobby Circuits
VU Meter Circuits
LED brightness control
555 Incredible Chip
Process Control
liquid level measurement
Thermocouples and RTD
Design ADC Interface uC
Thermocouple Amplifier
IA Instrumentation 02
Temperature on DMM
Optical Proximity Switch
Analog Mux - Data Acquisition


Test Measurement
Instrumentation Automation
NI Test and Measurement
DMM Digital Multi Meter
Oscilloscope in T&M
IA Automation 01
Build Instruments
Tektronix T&M Equipment
Educators Corner – Agilent


Power Electronics
UPS Background
Transformer Connections
DN Power Electronics 03
DN Power Electronics 02
Half Bridge Convertor SG3525


Embedded
Interfacing Microcontrollers
Embedded Process Control
80C31 8052 Microcontroller
Microprocessors and uC
Embedded Systems Design

Components
Good Voltage Regulators
Relays and Contactors
Potentiometers Trimpots
Prototype Boards Types
Types of Capacitors
Types of Switches
Resistors How they Work
Coils Transformers SMPS
Mains Transformers Types
DN Components Selection 05

Tutor Gadgets
Count-Up Timer
Digital Logic Gates
Electronics Tutors

History
Teaching Instruments
Charles Proteus Steinmetz
Muntzing a Circuit Design
Teralab Electronics projects
Historical Instruments


Tables, Charts, Videos
Binary and Hex
Resistor Color Code
Ohms Law
Giga, Tera, Pico, Nano
High Resistance Materials

Analog
School - Analog Design
DN Analog Basics 06
DN Op-Amps 01
TI Semiconductors