Hi,
I have an issue while trying to save energy with my Arduino.
So I would like to put him in sleep mode every 10 hours and than wake up. I need to do tracking and monitoring of solar system in real time. Im using Arduno uno, Pololu High-Power 18V, 15A motor driver and 12V DC worm gear motor. How much energy I will save ( and how much power consumption) in sleep when using an internal clock solution with some watch dog timer and internal clock ( if possible for real time tracking and monitoring) . Is it external Real Time Clock better solution regarding saving energy ?
Any help what solution is better one and what do I need for that solution?
Depends which board you use. On the Uno the USB->serial chip will consume power whether or not
you shutdown the ATmega328, so you don't get much saving, so its probably not the right choice.
Do need to measure your current drain of the Pololu H-bridge too - this may need powering down
which could be an issue (you fail to provide a link so we can't check its specs - always provide a
link to any equipment if you want knowledgable answers (or read the datasheets!)
The Arduino Uno uses the ATmega328P microcontroller. That microcontroller can be set in a sleep mode to draw only a few micro amps. However, the other components on the Uno board will still keep on using power.
For a custom design or for a barebone ATmega328P circuit, it can be very useful to use the sleep mode. But for the Uno board, that is not very useful.
You could do a test. Use a not-so-deep sleep mode, that keeps all timers and interrupts running. At the end of the loop() function enter that sleep mode. It might result in a few milli-amps less current use.
Some notes about the sleep mode:
Going into sleep mode for 10 hours, means that the Arduino wakes up every few seconds and goes back into sleep mode. That is normal, even if the Arduino wakes up a few times per second.
The best sleep mode is using the WatchDog timer, but then the Arduino has no accurate clock anymore. A RTC would be needed in that situation.
I can't find a schematic of that pololu driver. I also can't find which driver chip is used.
The conclusions is still the same: you could put the ATmega328P chip into sleep mode, but it won't make a big difference, since other components on the Uno board and on the Motor Driver board will still use current.
How is the Arduino powered ? What battery ? How is that charged ? How many days should the battery last (when there is no sunshine) ?
If you for example connect 12V to the power jack of the Arduino Uno, then most energy is wasted in the voltage regulator.
It is possible to use a 3.3V 8MHz Arduino Pro Mini, remove the leds and voltage regulator, and power it with 3 AA batteries to VCC. With the sleep mode it will run for years.