Excuse me, can any one help me with my project. I am going to build a solar tracker but i found out that the LDR of my circuit always have not equal resistance during night causing the motor run non stop at night. I try buy 4 to 5 set of LDR but all the resistance not equal. I am using the comparator to control the solar tracker.
You can try with two parallel resistors to the LDRs. They will keep the bridge mostly balanced at low light intensity. Ultimately there should be an additional LDR with a comparator that shuts the tracker down below a certain brightness.
Excuse me, can any one help me with my project. I am going to build a solar tracker but i found out that the LDR of my circuit always have not equal resistance during night
So I need to use a microcontroller to control the solar tracker ??? In my circuit it doesn't consist of microcontroller to control the operation. I use a comparator to compare the voltage from LDR then drive the motor
So I need to use a microcontroller to control the solar tracker ??? In my circuit it doesn't consist of microcontroller to control the operation. I use a comparator to compare the voltage from LDR then drive the motor
You can try with two parallel resistors to the LDRs. They will keep the bridge mostly balanced at low light intensity. Ultimately there should be an additional LDR with a comparator that shuts the tracker down below a certain brightness.
You can try with two parallel resistors to the LDRs. They will keep the bridge mostly balanced at low light intensity. Ultimately there should be an additional LDR with a comparator that shuts the tracker down below a certain brightness.
Using a resistor across each LDR is the cheapest option. What value is the question - depends on how sensitive the comparator is. It has to be small enough to negate the difference in the dark, yet large enough to not to unduly influence the tracking of the sun.
I agree there ought to be a circuit to shut down the tracker at night.
you don't say whether its polar or azimuth tracking that is faulty. I would use a "master" LDR that when the light has fallen sufficiently returns the polar tracking to due west and the azimuth to 0 degrees then shuts it down until the sun rises the next morning.
Frank