Car Battery 12v Charger

The usual chargers of battery automotive, are simple and cheap appliances that charge continuously the battery, with a rythm of few amperes, for the time where the appliance is ON. If the holder do not close in time the charger, the battery will overcharge and her electrolytic faculty are lost with evaporation or likely exists destruction of her elements. The charger of circuit exceeds these faults. It checks electronic the situation of charge of battery and it has circuit of control with retroaction, that forces the battery charge with biggest rythm until charge completely.

Circuit diagram:

Car Battery 12v Charger Circuit Diaram

When charge completely, it turns on one RED led (LD2). The charger has been drawn in order to charge batteries of 12V, ONLY. What should watch it from what it manufactures the circuit, they are the cables that connect the transformer with the circuit and in the continuity the battery, should they are big cross-section, so that heat when it passes from in them the current of charge and also they do not cause fall of voltage at the way of current through them.

Adjustment

After assembling of the circuit, adjust TR1 to null value, power-up and make the following adjustments :-

1. Without connecting the battery check that the 2 LED?s are turned on.
2. Connect a car battery to the circuit and check that LD2 is OFF and a current (normally 2A to 4A) is flowing to the battery.
3. Adjust TR1 until LD2 turns ON and the charge current is cut.
4. Adjust TR1 to null value and charge the battery using the hydrometer technique (if you do not have or do not know how to use a hydrometer, then use a good condition battery and charge).

Carefully adjust TR1 so that LD2 begins to turn ON and the charge current falls to a few hundred milliamps (mA). If TR1 is set correctly then in the next round of charging you will noticed LD2 begin to flicker as the battery is being charged. When battery is completely charged, LD2 turns ON completely.TR1 does not need further adjustment anymore. Q1 is connected in line with the battery and is fired by R3, R4 and LD2. The R2, C1, TR1 and D2 sense the voltage of the battery terminal and activate Q2 when the voltage of the battery terminal exceeds the value predetermined by TR1.

When an uncharged battery is connected, the terminal voltage is low. Under this circumstance, Q2 is turned OFF and Q1 is fired in each half cycle by R3, R4 and LD2. The Q1 functions as a simple rectifier and charges the battery. If the battery terminal voltage is increased above the level that had been fixed by TR1, then Q2 shifts the control of Q1 gate. This deactivates Q1 and cuts off the current supply to the battery and turns LD2 ON indicating that the charge has been completed. Q1 and bridge rectifier GR1 should be mounted on heatsinks to prevent overheating. M1 is a 5A DC ammeter to measure the charge current.

Source :users.otenet.gr

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How to Installation A Car Stereo

Car Stereo Installation Guide - Want to save some money? Ever wonder if you could do a car stereo installation yourself? Yes, you can do it yourself! Go ahead, spend that money on your hardware! Don’t spend it on labor. Besides, doing a car stereo installation yourself can be a very rewarding experience, not to mention you can learn a lot from it too. Nothing beats the feeling of seeing your “creation” in action, running smoothly and perfectly.

But be very careful, you really won’t want to damage your expensive hardware. Well, most car audio hardware are no-brainers to install, you’d find that most of the time the parts have specially shaped sockets and slots etc. and would only fit where it’s supposed to be installed. Still, it’s best to proceed methodically.

In a car stereo installation, you have to determine what kind of rig you’re going to put into your vehicle. If you’re a beginner, it’s best you do a car stereo installation if it’s just a simple system. You may want to leave the complicated stuff to the professionals, like installing delicate equipment like LCD panels, motorized parts etc. especially if it requires the creation of custom panels and such. 

Head units are one of the easiest to do in a car stereo installation. Fortunately, most units follow the same size standards (DIN). In many cars, once the factory radio is removed the aftermarket radio will fit in the hole. In many other cars, a kit is needed if the factory hole is too big, or not deep enough. In some cases the dash has to be cut.  Any car stereo store should have kits required for installation. 

There are two types of mounting in a car stereo installation. ISO mounting is when the radio can be screwed to existing factory radio brackets, such as in most Japanese cars. Ring mounting is when an aftermarket radio comes with a metal ring that gets mounted to the factory radio hole or aftermarket kit via bendable tabs. In many cars, dash and trim rings have to be filed to enlarge the radio hole. Once the ring is installed, the radio slides in and is held by snaps. In most cases, special tools are required to remove the radio.

Speakers are very critical in a car stereo installation. No matter how expensive your speakers are, if they are not properly installed, the sound will not be up to par.

In a simple car stereo installation, you’ll probably be using speakers that fit into a factory location. Just make sure there are no gaps or holes. Sometimes building a wood or fiberglass baffle helps reduce holes and gives you much better sound. But always be careful when using power tools around speakers. Car stereo installation warranties usually dont cover holes in speakers.

For unconventional speaker locations, sometimes metal has to be cut. You might want to leave this to the professionals, tools like plasma cutters and pneumatics drills are required. But if you’re going to insist, a pair of metal snips (left and right cut) will do.

A car stereo installation has to put up with vibrations and other noise sources in its environment. Even though it is impossible to eliminate these completely, there are products that will greatly decrease the noise and rattling, particularly on non-luxury cars. Liners, sprays and adhesive strips and even carpeting applied onto the panels can make a world of difference.   

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