Hi everyone,
I am not a pro in electronics. In my spare time I build electronics gadgets. This is like hobby for me. I wanted to build a water level indicator and searched through the net for one. I got a good circuit diagram (here is the link http://www.electronicsforu.com/efylinux/circuit/cir105.htm)from a good site and started to build the thing. After two days of work I finally completed the circuit. It works fine but I a stuck in one place.
This is the Circuit Diagram http://www.electronicsforu.com/efylinux/circuit/cir105.gif
The circuit is working fine except the LED marked LED1 does not light up at all. Normally LED1 should light if the water level is below level L2 but above L1 thus connecting L1 metal strip with the Long Main Lead.
I have checked the circuit. The problem I noticed here is that the LED1 is not getting the Minimum Threshold Voltage to light Up. It is getting around 1.25volts which is insufficient for lighting up the led (this Should be anything in between 2.5 to 5.5volts).
On more thing happening here is that when water drops below L1, the voltage across the LED1 drops to half (0.6volt) now the circuit is built in such a way that this should happen ; only the drop should be from (2.5 to 5.5volt) to around 1.25volt.
So as per my inference goes the problem is this :
The voltage across LED1 is 1.25volt instead of 2.5 to 5.5volt when water level is above L1
The voltage across LED1 is 0.65volt instead of 1.25volt when water level is below L1
Rest of the LEDs are getting around 5.5volts each and are working fine.
Now can anyone help me out of this problem please. I am unable to figure out where the problem might actually be.
Thanks in advance
Abhi
I am not a pro in electronics. In my spare time I build electronics gadgets. This is like hobby for me. I wanted to build a water level indicator and searched through the net for one. I got a good circuit diagram (here is the link http://www.electronicsforu.com/efylinux/circuit/cir105.htm)from a good site and started to build the thing. After two days of work I finally completed the circuit. It works fine but I a stuck in one place.
This is the Circuit Diagram http://www.electronicsforu.com/efylinux/circuit/cir105.gif
The circuit is working fine except the LED marked LED1 does not light up at all. Normally LED1 should light if the water level is below level L2 but above L1 thus connecting L1 metal strip with the Long Main Lead.
I have checked the circuit. The problem I noticed here is that the LED1 is not getting the Minimum Threshold Voltage to light Up. It is getting around 1.25volts which is insufficient for lighting up the led (this Should be anything in between 2.5 to 5.5volts).
On more thing happening here is that when water drops below L1, the voltage across the LED1 drops to half (0.6volt) now the circuit is built in such a way that this should happen ; only the drop should be from (2.5 to 5.5volt) to around 1.25volt.
So as per my inference goes the problem is this :
The voltage across LED1 is 1.25volt instead of 2.5 to 5.5volt when water level is above L1
The voltage across LED1 is 0.65volt instead of 1.25volt when water level is below L1
Rest of the LEDs are getting around 5.5volts each and are working fine.
Now can anyone help me out of this problem please. I am unable to figure out where the problem might actually be.
Thanks in advance
Abhi