Thursday, August 15, 2013

Select a Fuse and Fuse Holder For Your DC Product Installation

This is the second in a three part series of technical briefs on circuit protection. Part 1 showed how to choose the correct wire size for DC circuits, and Part 3 will detail how to select a circuit breaker when installing an AC or DC product.
U.S. Coast Guard regulations, and ABYC E-11.10.1.1.1, require every ungrounded wire except those in the engine starting circuit to have circuit protection. Many DC installations employ fuses rather than circuit breakers. Choosing correct fuse amperage and the best fuse holder or fuse block will help protect your boat and your safety.
Always select a fuse size to protect the wire according to its rating. In some cases, a product manufacturer will specify a fuse value and it will usually be lower than that required for protecting the wire. If this fuse value is too high to protect the wire, use a bigger wire in the circuit. Review Part 1 for more information on choosing wire size for a DC circuit.
Follow the steps to choose fuse amperage and a fuse holder or fuse block.
Choosing the Fuse Amperage
In this step, find appropriate fuse amperage within a range of minimum and maximum
A  Find the MAXIMUM FUSE AMPERAGE by following your AWG wire size (from Part 1 of this series) across the chart. Maximum fuse amperage reduces nuisance blows but offers less protection for the wire. Select:
  • Single Wire or Bundled Wire column, and
  • Outside Engine Room or Inside Engine Room grey bar
Example: For a 4 AWG single wire outside an engine room, maximum fuse amperage is 150A.
B  Calculate MINIMUM FUSE AMPERAGE by multiplying product amperage rating by 125%. Minimum fuse amperage provides more protection for the wire but may result in nuisance blows.

Example: 80A x 125% = 100A.
C  Choose FUSE AMPERAGE near the middle of this range. Mid-range values are usually acceptable. Consider the requirements for each individual circuit.

Example: 125A is between 100A minimum and 150A maximum.
D  Find AVAILABLE FUSES by using the chart.

Example: Fuses available at or near 125A include MIDI®/AMI®, MRBF, MEGA®/AMG®, and ANL fuses.
Choose a Fuse Holder or Block
With fuse amperage and available types in mind, find the right fuse holder or block
A  Using the same colored headings as in the steps abovefollow the columns down to find fuse holders or blocks that meet your specific requirements.
B  Consider environmental factors
  • Insulating covers protect fuses from accidental shorting
  • Ignition protection is required where flammable vapors may accumulate
  • Ingress protection protects fuses from spray, washdown, or humidity
C  Decide between an in-line fuse holder or block
  • Fuse holders are compact and hold a single low-amperage fuse
  • Fuse blocks mount to a solid surface and may hold a single fuse or multiple fuses

Choosing the Correct Wire Size for a DC Circuit

Choosing the right wire size for your DC electrical project is important, since a wire that is too small can overheat and possibly start a fire. The American Boat and Yacht Council (ABYC) publishes charts with valuable detail to help experienced boatbuilders and installers determine what wire size they need. Although these charts are an excellent resource, they are a bit intimidating. This technical brief distills the information on these charts to a more manageable size for installers and boatowners alike.
Quality marine wire, as specified by ABYC standards, will always be stranded rather than solid, and always tin-plated copper. In addition, the DC Wire Selection Chart shown below assumes a wire insulation rating of 105°C. A lower rating will decrease the current-carrying capacity of the wire.
To use the chart included with this technical brief, follow the instructions below.
Choosing the correct wire

A  Locate the CURRENT IN AMPS of your appliance across the top of the chart. Most electrical products include a rating label, or you can find the amperage rating in the documentation that came with the product.
B  Find circuit LENGTH IN FEET along the left side of the chart. Note that the total length of the circuit is the roundtrip distance from power source (usually the battery) to the product and back.
C  Select the CIRCUIT TYPE. Allowable voltage drop is based on whether a circuit is critical or non-critical.
Critical circuits, with 3% allowable voltage drop, include
  • Panel main feeders
  • Bilge blowers
  • Electronics
  • Navigation lights
Non-critical circuits, with 10% allowable voltage drop, include
  • General lighting
  • Windlasses
  • Bait pumps
  • General appliances
Follow down the column until you find your circuit’s LENGTH IN FEET.
D  Intersect CURRENT IN AMPS with LENGTH IN FEET to identify the wire size.
Example: A windlass rated 80A is 25’ from the battery. Circuit length is 50’, circuit type is ‘non-critical’, and correct wire size is 4 AWG.

Electronic Projects

Welcome to the Dilshan R Jayakody's Project Repository


In this wiki we publish all the electronic, computer and mechanical projects which we described in Dilshan R Jayakody’s Web Log. Please select the project(s) from the following list to obtain more details,

3.3V - 1.5A Compact Power Supply Unit
1.5A - 3V to 27V adjustable power supply using LM723
433MHz RF remote control system for RC Cars
9 Pin dot matrix printer using PIC16F84A
AT89S52 base RPM counter
Automated Telephone Remote Control
Compact logic probe with digital pulser
Home produced USB Sound Card
Low Cost and High Quality Stereo FM Radio Receiver
PS2 Keyboard driven Morse code Generator
Simple ATMEL AVR - Programmer
User Programmable Automatic Night Light
Low Dropout Single Rail Adjustable Power Supply Unit
20W Hi-Fi Audio Power Amplifier
Automated Home Security System
12V DC to 230V AC Inverter
Homemade ADSL Splitter
4 Channel Remote Control Video Switch
Ultra Simple Stereo Computer Speaker Driver
8 pin 2 digit seven segment display driver
Virtual MCU Base Programmable Timer
Electronic Number Panel
8 Channel USB Logic Analyzer
2 Channel Electronic Motor Speed Controller
Low Voltage Simple Motor Speed Controller
Programmable Home Security Alarm System
32W Hi-Fi Audio Power Amplifier using TDA2050
Electric Fence with Automated Monitoring System
Mini Servo Controller
PIC16F877A/PIC16F887 Microcontroller Development Board
XBMC USB Controller
Ultra Simple Microchip PIC Development Board
Microprocessor controlled CW Beacon
Extend PIC Microcontroller‘s RAM by without using EMI
5V 5A Bench Power Supply
Offline High Voltage AC Power Supply
LASER Based Gate Keeper
LEDShoot - Electronic LED Shooting Game
Simple ATmega325 Development Board
Replacement Code Lock for LS7220 base Systems
DIY Liquid Level Monitor and Automatic Control System
USB Custom Hardware Interface for Unity3D

Monday, July 15, 2013

Transistors

In the old days a magazine used the terms TUN and TUP
There was the TUN (transistor universel NPN):



There was the TUP (transistor universal PNP):



They also publised parameters for them:



And pinouts:

Thursday, June 27, 2013

8051 Microcontroller – Programming Tutorials, Simulators, Compilers and Programmers

8051 is not just a number, is the name of one of the most advanced microcontroller used in robotics. This single chip microcontroller is a box where are stored many functions like CPU, RAM, ROM, Timer, Serial Communication Interface, I/O ports, etc. First version appeared in 1980s and since then the microcontroller is a popular chip for embedded systems.

The 8051 microcontroller is a small computer based on architecture with support for embedded applications. This is the biggest difference between a microcontroller and microprocessor. A microprocessor is used in personal computers while a microcontroller is used for embedded systems especially in robotics.
8051 Microcontroller
8051 Microcontroller

Since 8051 is the most common microcontroller designed especially for robots, I decide to write an article with resources for beginners and advanced users. In this article, I include resources for programming, simulation, compile, programmer kits and especially tutorials to learn how the 8051 microcontroller is programmed or simulated.

8051 Microcontroller Programming Tutorials

Beginners or advanced users can read these tutorials for educational purposes to learn how to programming a 8051 microcontroller or used for inspiration in case of advanced users.

Simulators

Useful tools designed to be used in development process for 8051 microcontrollers.
  • Raisonance – application simulator for 8051 microcontrollers.
  • JSIM51 – free simulator for 8051 microcontroller and one of the most popular simulator with comprehensive documentation to learn how can be used.
  • Micro C 8051 – simulator C and assembly programming language compatible.
  • C51 Software – simulator tool for classic and extended 8051 microcontrollers.
  • Proteus VSM for 8051 – complete tools for develop and test programming line for all series of 8051 microcontrollers.
  • Crossware 8051 – simulation tool that creates a virtual clone of 8051 microcontroller that runs on computers.
  • EdSim51 – one of the most popular simulator tool for 8051 series with interface for virtual peripherals and keyboard, ADC, or DAC.
  • Tiny 8051 Microcontroller Simulator 0.6.1 – designed for educational purposes, Tiny is a simulator written in C# programming language for simulation and debugging.

Compilers

List with C or C++ compilers and support for 8051 microcontroller series.
  • SDCC – C compiler for a wide series of microcontrollers including the 8051 model.
  • mikroC PRO for 8051 -C compiler with friendly interface and support for Atmel and Silicon Labs microcontrollers.
  • Keil – powerful and efficient C simulator for 8051.
  • TASKING – compiler compatible with 8, 16 and 32-bit microcontrollers.
  • IAR Embedded Workbench for 8051 – C and C++ compiler for 8051.
  • 8051 C Compiler – based on ANSI standard, the Crossware 8051 C compiler is designed for 8051 microcontroller series.
  • 8051 C++ Compiler – C++ simulator with support for object oriented programs.
  • Ceibo 8051 C++ – C++ compiler with support for Object Oriented Programming and used for debugging and code maintenance.
  • 8051 C-Compiler uC51 – friendly interface tool based on ANSI C standard.

Programmer

In this section I made a list with hardware devices called programmer and used to write in the 8051 microcontroller memory the machine language code.

8051 Microcontroller Instructions Set

For a precise control, the microcontrollers may operate under instructions. These instructions are commands written for microcontroller and divided into various categories including arithmetic, logic, data transfer, Boolean variables, and machine control instructions.

Monday, June 24, 2013

EAGLE PCB Software

Whether you are a team of one, or part of a large engineering department, EAGLE provides quality PCB design software with the features that get the job done. For over 20 years, EAGLE has been satisfying design engineers around the world, by offering the same core functionality as expensive commercial software, at the fraction of the cost.
Easy to learn
  • Schematic editor, layout editor, library editor modules with identical user interfaces
  • Free service support through dedicated experts
  • Compatible with Windows®, Linux®, Mac®
Easy to buy
  • Purchase and license on-line or with personal support from our distributors
  • No maintenance fees or add on contracts
Easy to use
  • Flexible User Language Programs (ULPs) enable custom features, such as individual instruction sequences, simulation, data export and import
  • Export Gerber files that can be used at any board house:
    • Gerber 274X & Gerber 274D
    • Excellon NC Drill Format
    • SM1000 and SM3000
    • Custom user-defined export formats
  • Online import of product & pricing information through DesignLink
  • Active customer forums to share files, libraries ULPs, design tips and more
System Requirements
Windows
  • Windows 2000, Windows XP, Windows Vista or Windows 7
Linux
  • Intel PC based Linux
  • Kernel version 2.6
  • X11 in at least 8bpp mode
Mac
  • Mac OSX 10.4 on PPC or Intel


Windows users please download the file
ftp://ftp.cadsoft.de/eagle/program/5.11/eagle-win-5.11.0.exe





Linux users please download the file
ftp://ftp.cadsoft.de/eagle/program/5.11/eagle-lin-5.11.0.run

Further download directories can be found here:
Addendum – Important fixes that have been applied after the release of EAGLE version 5.0
Libraries – New and improved EAGLE part libraries
ULPs – User Language Programs
Projects – Projects from EAGLE users
Documentation – Various user provided documents
Tools and Converters – Additional tools and converters to use with EAGLE

OrCAD PCB Designer Lite DVD

OrCAD 16.5 Demo Software (All Products)
Designers around the world rely on the powerful yet intuitive Cadence® OrCAD® personal productivity tools. OrCAD has a long history of providing individuals and teams with a complete set of technologies that offer unprecedented productivity, seamless tool integration, and exceptional value—the OrCAD 16.5 release continues with that tradition.

The OrCAD 16.5 demo software will let you experience all the features and functionality of the actual software*. So go ahead, discover how easy it is to use these state-of-the-art OrCAD technologies.

* Limitations are in the size and complexity of the design.

The OrCAD PCB Designer Lite DVD includes demo versions of the following tools: OrCAD Capture, OrCAD Capture CIS Option, PSpice® A/D, PSpice A/A, OrCAD PCB Editor and SPECCTRA® for OrCAD.

Download FREE - OrCAD 16.5 demo software (851MB) includes OrCAD Flow Tutorial with the example design files (You must use the path/folder option in your zip tool when extracting this archive.)