This is a 9v battery status indicator circuit.One of my friend asked me to build this as he wants a 9v transistor radio battery status indicator. Thats why i build this circuit it works great and another thing about this circuit by changing the 'ZENER diode" you can rebuild this circuit for other low power battery. I used Green and Red led as green Led light's up when the voltage is upper than 6.9v and Red led lights up when the voltage drops to 6.9v . Its simple and reliable all the parts are commonly available and low cost also. 

parts List :

Led (RED & Green )
ZENER 6.2v (for using with 9v battery)
<p>sir can i ask for a ckt for 6V battery status indicator? thank you!</p>
<p>please reply me as quick as you can.</p>
<p>First time, I build this circuit, I also faced a problem, where two LEDs lit up when voltage is above than set value which determined by zener diode. So, I make some modifications on its base resistor at transistors, and it worked out. Hope it will help you guys! Done with Proteus 8</p>
<p>Conzrzzzzzzz ......</p>
<p>This circuit sound great to make a flip flop circuit however I have tried in Multisim and the red and green light both are lighting till 6,9 volts. </p><p>Actually, I would like to make this circuit in 7,4 lithium battery and I have tried to calculate the reistance and I find it quite difficult.</p><p>Do you know any page to calculate it, or could you show your results in your project.</p><p>Thanks,</p>
<p>sir can i ask for a ckt for 6V battery status indicator? thank you! :)</p>
please give me a NP4.5 6v 5Ah battery charging indicating circuit diagram
<p>Ok i will try bt it will take little time </p>
<p>sir how to set low led indication for 4v and high led for 8v.. can u help me???</p>
<p>First of all change the Zener diode as you need. Than set the circuit </p>
<p>Hi do you have a picture of the built circuit? ive been trying to replicate it on a breadboard and couldnt get it to work. thanks</p>
<p>Sorry my frnd i don have any picture of the above circuit </p>
<p>Hi there!I just made this circuit and when battery level is above 6.9 v both leds light..Just when the battery level is under 6.9v only the red led lights.</p><p>I mean that the red led is always on when connected to battery.Is that ok?</p>
<p>&quot;green Led light's up when the voltage is upper than 6.9v and Red led lights up when the voltage drops to 6.9v&quot; </p><p>Check your circuit properly</p>
<p>Does it matter that I used 2 BC546b tranzistors instead of BC547?</p>
yes it does matter wid that. bc547 most common parts.
So could you do this with a 12 volt battery and 4 leds? and could you clarify what the zener 6.2v is?
they are rechargeable batteries (1.2v each), shall I use a 3.6v diode?
hoo yes u can try that .............
Thank you very much for your design, it's really useful to me. <br> <br>I got some questions, hope you can help me: <br> <br>- I would like to place 3 different LEDs on my circuit to indicate the charge level for a 4 AA rechargeable battery pack. They all together and completely charge would give me 4.8 volts, which Zener diode do you suggest to me? <br> <br>- Could I use 1 zener diode and different resistors values to light up the different leds?
1sly.....1.5v x 4aa would give u 6v not 4.8v.......as far i think u could use a 4.8v zener.....try 2 build the circuit in bread board 1st...........
how can i create a 4.8v battery indicator??
Yep i think Green led will light up......but it will be for few sec's. just saying. Nd Adarsh 10q very much <br>
Hi, <br>suppose we have a voltage somewhere in between 5.9 volts and 6.9 volts.The red Led will definitely light up but will the green Led still continue to glow?.well,I know that the green Led will light up since it gets more than 5.9 volts but just wondering......and by the way you deserve some credit for this simple but creative model.
&quot;&quot;kurtselva&quot;&quot; these values came up experimenting with the circuit day's month's nd year's. Actually i can't explain ur 1st question and i suggest you that you should start experimenting with the circuit in a &quot;bread board&quot; nd see urself what comes out. Good Luck
Hi, <br> <br>May i know how you came up with the values for the resistors and zener diode? <br> <br>And how will the values change if I use a 1.5V battery source instead?

About This Instructable




Bio: m mad about electronics, technology........who m i ??? son just don ask that .......
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