Discharge Indicator Circuit for 12V Lead Acid Battery

Here the discharge indicator circuit for Lead Acid battery 12V. This circuit is used to prevent the batteries from damage. When discharging the battery voltage pin 12V Lead may not be reduced below 10.8V, so we notice the lighting of Led, when the voltage falls below this value. To achieve control we need a constant voltage and a circuit that can compare this with the controlled voltage. And these two conditions to ensure the IC1-LM 723.

The input terminals of the circuit connected to the battery terminals. In IC1/6 shows a steady trend of +7.15 V, when the input voltage is greater than + 9.5V. The constant voltage is applied to IC1/5. In IC1/4 applies a voltage of the input, controlled by the trimmer TR1. The IC1 is act as voltage comparator . So when the voltage at IC1/4 is greater than the voltage at IC1/5, then the output of IC1/9, is low [L], the Q1 is off and the LED is off. To turn the LED should the voltage at IC1/4 be less than the reference voltage at IC1/6, where the output of IC1/9 will be high [H], the Q1 conducts and LED lights.

To configure the circuit will need an external power supply, which will be configured to output a +10.8 V, we apply the input circuit. Adjust the trimmer TR1, so that lights the LED, with no decrease in the voltage of power supply. The input terminals of the circuit should be connected directly to the battery terminals and may be used when using batteries 12V (Lead Acid).

Comments

LM317T Voltage Regulator Circuit with Pass Transistor

This is the schematic diagram of voltage regulator circuit with pass transostor. The regulator is based regulator IC of LM317T. The LM317T output current can be raised by utilizing an additional power transistor (on circuit, it is 2N2955) to share a portion of the total current. The amount of current sharing is established with a resistor placed in series with the LM317 input and a resistor placed in series with the emitter of the pass transistor. In the above scheme design , the pass transistor will start conducting when the LM317 current reaches about 1 ampere, due to the voltage drop across the 0.7 ohm resistor. Current limiting happens at about 2 amperes for the LM317 which will drop about 1.4 volts across the 0.7 ohm resistor and make a 700 millivolt drop across the 0.3 ohm emitter resistor. Thus the total current is limited to about 2+ (.7/.3) = 4.3 amperes.

Sealed Lead Acid (SLA) 12V Battery Charger with Current Limiting

This is the circuit design of Smart Sealed Lead Acid (SLA) 12V Battery Charger featuretwith Current Limiting. The charger uses a two step process for charging SLA batteries – a current limited ‘fast’ mode followed by a constant voltage ‘float’ mode. Maximum charging current is 1A. An onboard LED indicates when the charger is in ‘fast’ mode. When the LED goes out the battery is charged and the charger has switched to ‘float’ mode.

Unregulated Dual Polarity Power Supply

This is the schematic diagram of Unregulated Dual Polarity power supply . Unlike 78xx and 79xx dual polarity regulated power sypply and LM317/LM337 dual polarity regulated power supply which have limited current output and voltage (have limited supply power), this unregulated power supply will give you more power. This kind of circuit usually used for power amplifier which need high supply power, or as high current lead acid battery charger (single polarity only). The component value is flexible refer to your needs. For example: if you need power supply for 100W amplifier, then the component value are: Transformer: 3A minimum (center tap) Diodes: 3A diode (1N5401, 1N5402, 1N5403 etc) Electrolytic capacitor: 4x minimum of 4700uF/50V (the higher is better - check the capacitor voltage, change it for higher voltage. example: use 63V capacitors for 45V power supply output.)

Power Supply Adapter

Search This Blog