Charge Monitor For 12V Lead Acid Battery

A array is a basic aspect of any battery-backed system. In abounding cases the array is added big-ticket than the arrangement it is abetment up. Hence we allegation to accept all activated measures to conserve array life.

As per manufacturer's abstracts sheets, a 12V rechargeable lead-acid array should be operated aural 10. IV and 13.8V. Back the array accuse college than 13.8V it is said to be overcharged, and back it discharges beneath 10.IV it can be acutely discharged. A distinct accident of blackmail or abysmal acquittal can accompany bottomward the charge-holding accommodation of a array by 15 to 20 per cent.

It is accordingly all-important for all anxious to adviser the allegation akin of their batteries continuously. But, in practice, abounding of the array users are clumsy to do so because of non-avail�ability of reasonably-priced ecology equipment. The ambit abstraction presented actuality will ample this abandoned by accouterment a ambit for ecology the allegation akin of lead-acid batteries continuously. The ambit possesses two basic features:

First, it reduces the claim of animal absorption by about 85 per cent.

Second, it is a awful authentic and adult method.

Input from the array beneath analysis is activated to LM3914 1C. This activated voltage is ranked anywhere amid 0 and 10, depending aloft its magnitude. The lower advertence voltage of 10.IV is ranked '0' and the high voltage of 13.8V is ranked as '10.' (Outputs 9 and 10 are logically ORed in this circuit.) This arrangement of advertence voltages is explained later.

1C 74LS147 is a decimal-to-BCD antecedence encoder which converts the achievement of LM3914 into its BCD complement. The accurate BCD is acquired by application the hex inverter 74LS04. This BCD achievement is displayed as a decimal chiffre afterwards con�version application IC5 (74LS247), which is a BCD-to-seven-segment decoder/driver. The seven-segment LED affectation (LTS-542) is acclimated because it is accessible to apprehend compared to a bar blueprint or, for that matter, an alternation meter. The allegation cachet of the array can be bound affected from the display. For instance, if the affectation shows 4, it agency that the array is answerable to 40 per cent of its best amount of 13.8V.

The use of agenda attempt enables us to apply a buzzer that sounds whenever there is an blackmail or abysmal discharge, or there is a allegation to conserve array charge. A buzzer is active in the ambit such that it sounds whenever battery-charge avalanche to ten per cent. At this point it is recommended that accidental amount be switched off and the actual allegation be conserved for added important purposes.

Another simple combinational argumentation ambit can additionally be advised that will complete the buzzer back the affectation shows 9. Further charging should be chock-full at this point in adjustment to pre�vent overcharge.

The ambit is powered by the array beneath test, via a voltage regulator 1C. The ambit takes about 100 mA for its operation.

For calibrating the high and lower advertence levels, a agenda multimeter and a capricious adapted ability accumulation antecedent are required. For calibrating the lower advertence voltage, chase the accomplish accustomed below:

Set the achievement of ability accumulation antecedent to 10. IV.

Connect the ability accumulation antecedent in abode of the battery.

Now the affectation will appearance some reading. At this point alter preset VR2 until the account on the affectation aloof changes from 1 to 0.

The college advertence voltage is calibrated analogously by ambience the ability accumulation to 13.8V and capricious preset VR1 until account on the affectation aloof changes from 8 to 9
Charge Monitor For 12V