charge monitor for 12V car battery circuit diagram


Posted on Feb 5, 2014

A battery is a vital element of any battery-backed system. In many cases the battery is more expensive than the system it is backing up. Hence we need to adopt all practical measures to conserve battery life. As per manufacturer`s data sheets, a 12V rechargeable lead-acid battery should be operated within 10. IV and 13. 8V. When the battery charges


charge monitor for 12V car battery circuit diagram
Click here to download the full size of the above Circuit.

higher than 13. 8V it is said to be overcharged, and when it discharges below 10. IV it can be deeply discharged. A single event of overcharge or deep discharge can bring down the charge-holding capacity of a battery by 15 to 20 per cent. It is therefore necessary for all concerned to monitor the charge level of their batteries continuously. But, in practice, many of the battery users are unable to do so because of non-avail ability of reasonably-priced monitoring equipment. The circuit idea presented here will fill this void by providing a circuit for monitoring the charge level of lead-acid batteries continuously. The circuit possesses two vital features: Input from the battery under test is applied to LM3914 1C. This applied voltage is ranked anywhere between 0 and 10, depending upon its magnitude. The lower reference voltage of 10. IV is ranked `0` and the upper voltage of 13. 8V is ranked as `10. ` (Outputs 9 and 10 are logically ORed in this circuit. ) This calibration of reference voltages is explained later. 1C 74LS147 is a decimal-to-BCD priority encoder which converts the output of LM3914 into its BCD complement. The true BCD is obtained by using the hex inverter 74LS04. This BCD output is displayed as a decimal digit after con version using IC5 (74LS247), which is a BCD-to-seven-segment decoder/driver. The seven-segment LED display (LTS-542) is used because it is easy to read compared to a bar graph or, for that...




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    18-bit ADC uses PC`s serial port
    Infrared Interruption counter
    Linear scale ohmmeter
    Mini Logic probe with transistor circuit
    level shifting Increasing Voltage
    portable mixer block diagram
    3W FM Transmitter Circuit
    balanced ground
    Current source circuit diagram of the operational amplifier and Darlington transistors
    2Y- connection two-speed motor contactor control circuit 2



    Top