Saturday, September 22, 2007
I could not download pdf schematics file. Could you send me please?
Mail from WV
See some circuits here ...
You have to ensure at least a min of 15V AC to the Bridge or diodes on transformer. Only if a DC of around min 17V is available at input DC of 13.5 can be managed by this circuit. This circuit will not boost a voltage from a lower value for that you need Switching Boost Supplies.
Use AC Voltage Stabilizers or ServoStabilizers to maintain a stable AC Supply.
Simple Workbench Dual Power Supply
.....I like to compare with my schematics from our power supply. We have something very strange.. the backup battery takes over and don't cause a voltage drop when I disconnect power supply from 220V AC lines.. but the backup battery can not anticipate the disturbances in the 220V AC lines and gives a very short power drop at the output..
We have sometimes very short power drops at the output of the power supply.. Do you have any idea what is wrong? The transformer is 16V AC 3A
Reply from WV
You can double the size of filter caps at input. use something like 10,000uF, if you draw 3A a 10000uf across the input rectifier may help. Or you have to use a battery of 12V after the LM317. So that the battery can supply the short outages.
But that is exactly my problem, we have a large battery after the power supply of 13,5V 5,5Ah, but it doesn't help to avoid the powerdips after the power supply..
Reply from WV
I feel you have a ground loop problem, The wires to the battery seem thin. I feel the potential across a ground wire must be lifting up when mains fluctuates.
The PCB ground plane may be thin or absent, check all ground and supply wires. Make all supply wires and Tracks thick and radiate from a center copper lug reference. Both positive, negative and ground tracks reinforce with lead or copper braids. Use decoupling caps at every stage.
Sunday, March 25, 2007
Mail from SS
You can scan the manufactured objects with a camera connected to computer USB. Then compare the scans got with a reference standard. Apply a tolerance for acceptance or rejection. Based on the quantity of rejections improve process, till faults are within acceptable limits.
The scanned object must be in same position and same angle for proper results. This depend on some guiding system in conveyor to make object position properly.
Machine-vision system validates barcodes on packages within cartons.
Read This Interesting Article - Inside the Box Winn Hard
Friday, March 09, 2007
I was reading about some IC's from Maxim/ Dallas saying " Simple battery characterizer" for plotting a charging/ discharging cycles & graphs are available on computer for study I want to plot an extensive data of these batteries.
This circuit is a battery characterizer that applies a fixed load to a charged NiCad or NiMH cell and measures milliamp-hour capacity as it discharges.
Battery Characterizer: (Electronic circuit added 4/05). Battery Simulator Provides Current Limiting : 08/01/97 EDN Design Ideas / (added 5/03) A ... Battery Tester Electronic Circuits - www.discovercircuits.com.
Keywords: rechargeable AA cell, USB port, Visual Basic program, battery ... AA-Cell Characterizer software, written in Visual Basic, performs the cell ...
Simple Characterization Circuit for Rechargeable AA Cells - Maxim ... - www.maxim-ic.com.
Monday, February 12, 2007
I am trying to design a 4 door access controller. I have a complete working board of fingerprint scanner with DSP for fingerprint verification and authentication. I wish to design a microcontroller board which will communicate with this board to trigger the scanning process, store the data in PC and operate 4 relay circuits using the external wiegand relay output of the DSP. thanks in advance
Mail from RU
Have a look at these links
Look thru all the sites you may get ideas.
- HID Access Control
- Office Security FAQ
- Wiegand Definition
- Touch Card Technology
- Wiegand Readers - Honeywell Access Systems
- Wiegand Tech Overview
Elex Quna - 2008
- Using LEDs with Battery Power
- LF353 - Wide Bandwidth Dual JFET
- Insulation Resistance Analyzer Required
- Logic Analyzer on Computer
- Room Temperature Monitor and Alarm
- Orcad Spice Simulation CD4060
- Application for 8051 mcu project
- How does RTD Work
- Build RFID transmitter and receiver
- Continuity Tester
- Scart to RGBS Circuit
- 8254 Programmable Interval Timer Counter
- Ultra Sound Sender Detecter Diagram
- Understanding Transistor Power Dissipation
- Leakage of SSR driving AC Solenoid
- Hypersonic Speakers Acoustic Heterodyning
- SCADA System - Project Idea
- RTD Connections - 3W 4-20mA transmiter
- Battery Management and Supply Design
- Power Oscillator Circuit Design
Elex Quna - 2007
- Coffee maker PID Temperature Control
- Comparison of Thermocouple and RTD
- Door access controller
- Dynamic Digital Tutors
- Electronic Fifteen LED Roulette
- Electronic Projects Needed
- Flashing Neon lamp for Soldering iron
- Guard rings in strain gauge measurement
- how bently nevada proximity sensor works
- Mains Stabilty and Supply Regulation
- Metal Detector Circuits Problem
- PIC Projects and Circuits
- Polarized Capacitors and 555
- Power control and Robotics
- Precision Temperature Control with PID and SSR
- RS Latch Erroneously setting by Itself
- Significance of Current Loop 4 to 20 mA Standard
- Simple Battery Characterizer
- SSR Open Circuit Leakage Voltage
- uC Board is Misbehaving on Brown Out
- Ultrasonic distance measurement
- Usage of Schmitt trigger NAND Gates
- Visual Inspection for Quality Control