Battery Charger | Electronic Project Circuits

Posts Tagged ‘Battery charger’

Broken Charger-connection Alert

Detects if a device is not properly connected to its supply
Suitable for battery chargers, portable appliance supplies etc.

The circuit is inserted between the supply and the load, therefore, until a trickle-charging current of at least 100µA is flowing towards the load, D1 and D2 will conduct. The forward voltage drop (about 1V) available across the Diodes, drives Q2 into conduction and, consequently, Q1 will be cut-off.
If no appreciable load is connected across the circuit’s output, Q2 will become cut-off, Q1 will conduct and the Piezo-sounder will beep.

Parts:
R1______________10K 1/4W Resistor
R2_______________1K 1/4W Resistor
R3_______________1K 1/4W Resistor (Optional, see Notes)
D1,D2________1N4007 1000V 1A Diodes
D3______________LED Red (Optional, see Notes)
Q1,Q2_________BC557 45V 100mA PNP Transistors
BZ1___________Piezo sounder (incorporating 3KHz oscillator)

Please read more at the original source:http://www.redcircuits.com//Page86.htm
Thank you.

Be the first to comment - What do you think? Posted by admin - February 5, 2008 at 10:27 am

Categories: Audio diagram, Battery charger, Electronic Control Tags: Battery charger, protect Circuit, security circuits

Automatic 12V Lead Acid Battery Charger

Part
R1-R3= 330 Ohm 1/4W Resistor , R2 = 100 Ohm 1/4W Pot , R4, R5, R7, R8 = 82 Ohm 2W Resistor , R6 = 100 Ohm 1/4W Resistor ,R9 = 1K 1/4W Resistor
C1 = 220uF 25V Electrolytic Capacitor , D1 = P600 Diode Any 50V 5A or greater rectifier diode , D2= 1N4004 Diode,1N4002,1N4007,D3 = 5.6V Zener Diode , D4 = LED (Red, Green or Yellow) , Q1 = BT136 TRIAC , Q2 = BRX49 SCR , T1 = 12V 4A Transformer See Notes , F1 = 3A Fuse, S1 = SPST Switch, 120VAC 5A, MISC = Wire, Board, Heatsink For U1, Case, Binding Posts or Alligator Clips For Output, Fuse Holder

# R2 will have to be adjusted to set the proper finish charge voltage. Flooded and gel batteries are generally charged to 13.8V. If you are cycling the battery (AGM or gel) then 14.5V to 14.9V is generally recommended by battery manufacturers. To set up the charger, set the pot to midway, turn on the charger and then connect a battery to it’s output. Monitor the charge with a voltmeter until the battery reaches the proper end voltage and then adjust the pot until the LED glows steadily. The charger has now been set. To charge multiple battery types you can mount the pot on the front of the case and have each position marked for the appropriate voltage. [...]
Read more Source:http://www.aaroncake.net/circuits/charger2.asp

Be the first to comment - What do you think? Posted by admin - December 10, 2007 at 2:02 pm

Categories: Battery charger Tags: 12v car battery charger, Automatic Battery Charger, Battery charger

Make a Rechargeable Dual Voltage Power Supply for Electronic Projects

Mod a 9V rechargeable battery to give you +3.6V, Ground and -3.6V.
You will appreciate this idea if you ever had to clobber together a bunch of AAs or AAAs to get a project working.
This instructable was meant to be part of a larger project, but I decided to submit this part alone to the 9V battery group.
You need to start with a 9V rechargeable battery (actually 8.4V but in a 9V package).