Solar engine kit-suggestions

[saanvi]

Hi i am building the following circuit,i am using 1 farad cap instead of 4700uf,still i am not able to run my bot in low light,please suggest remidy

 

[Sceadwian]

Use a battery. No solar powered device can work in low light, it's a contradiction.

 

[surbhit]

HOW much light source (40w bulb ?) you are using and what about solar cell specification ?

 

[HarveyH42]

Your capacitor is twice the capacity, so it's going to take twice as long to charge up enough for the Flashing LED to fire, which switches on the motor, for about half a second. A smaller capacitor will charge quicker, and only has to provide enough current to spin the motor, since the solar panel can't provide it directly. The 1 farad cap might still work, but suspect it would need hours in low light to charge up enough for the initial pulse to the motor. You could add another solar panel in parallel to increase the charge current...

 

[Nigel Goodwin]

Your capacitor is twice the capacity, so it's going to take twice as long to charge up enough for the Flashing LED to fire, which switches on the motor, for about half a second.

I think you need to check your sums there!

 

[HarveyH42]

I think you need to check your sums there!

Oh, missed a couple of zeros... Should have been 200 times longer to charge? Really, not an engineer, just a hobbyist, the point was it would take much longer. But you are correct, it might take a day or two... Nothing to prevent the capacitor from discharging through the solar panel, when the lights go out...

 

[colin55]

1. How many mA is the solar cell providing under low-light conditions. What voltage. You need at least 3v-4v to get the LED to work.
2. Change the capacitor to 4,700u.
3. Some flashing LEDs will work, some will not, in the cirucit you have presented and some are photo-sensitive and need to be covered.
4. What type of motor are you using?