Wednesday, May 29, 2019

Dual Axis solar tracker without microcontroller

This circuit is a Dual Axis solar tracker without Arduino or any other microcontroller, using single IC LM324, 
By using Transistors BD139 and BD140 we can drive two motors with max. current 3A (for X-Axis and Y-Axis).
Parts list:
IC1=LM324
LDR (4pcs)
P1 & P3=Potentiometer 20K (2pcs)
P2 & P4=Potentiometer 200K (2pcs)
R1 & R2 & R11 &R12=Resistor 10 ohm (4pcs)
R3 & R5 & R7 & R10=Resistor 20K (4pcs)
R4 & R6 & R8 & R9=Resistor 33K (4pcs)
C1 & C3=Capacitor 220uF (2pcs)
C2=Capacitor 100nF (2pcs)
T1 & T2 & T7 &T8=Transistor BD140(4pcs)
T3 & T4 & T5 & T6=Transistor BD140(4pcs)
D1 to D9=Diode 1N4007(9pcs)
Switch
DC Motor with gearbox (2pcs)

Circuit:
To make dual axis solar tracker we have to make two identical circuit from this diagram:   
Dual Axis solar tracker without microcontroller

Dual Axis solar tracker without microcontroller


Since we need two op-amps for each axis, so i used IC LM324 which has 4 op-amps inside (for dual axis).
The diode through positive side of the battery used for reverse battery protection.
Two 20K resistors in series with LDRs used to decreasing LDRs current drawing, because they connected between VCC and GND as light sensor (voltage divider) and when exposed to direct sun the resistance of each LDR become around 300 ohm so the standby current drawing will be 9V/600 which is 15mA for each axis and 30mA for dual axis, but we can simply decreasing this current to only 440uA by using limiting current resistors without affecting the circuit performance.

Gerber file:

Dual Axis solar tracker without microcontroller

 Dual Axis solar tracker without microcontroller


3D Printed Solar tracker Files:


Dual Axis solar tracker without microcontroller

I used DC motor with gearbox like this https://www.banggood.com/custlink/33D35RebqC for each axis.

For more information please watch this video

Video: