Dear forum members,
this is my First post so I'm taking the chance to say hello.
i have a similar problem like crispy. I would like to shut down the power circuit depending on input voltage. The battery protection circuit that i have shuts down at 2.0 Volts per cell and I would like to shut the power at 2.5 V per cell (10 V total for a 4s battery). I would like to make a standalone battery power supply controlled by Arduino.
Can I use a voltage devider to sense the battery and a relay to shut down the entire circuit?
PB1 would be used to jump start the circuit until Arduino starts the program and turns on the relay so it holds the contact until the voltage drops below minimum alowabable treshold.
The same 4S LiFePo4 battery would be used to supply power to arduino nano over a 6V 3A UBEC (switching voltage regulator) and i would connect it to my further projects.
The First project where I would inplement this power supply is a RF 433 MHz controlled bulldouzer (4x24byj48 stepper motors on two A4988 drivers in parallel to lift and rotate the bucket and 4 x 6V geared motors (jellow) on L298N for wheels). It woild run on a seperate arduino Nano and the temperature sensors from the previous circuit would be mounted on the motors and battery so it shuts down if a motor gets jammed. It should all be Powered from the same circuit as possible.
So, my questions are the following:
Can i use this supply tu run two arduinos and 8 motors or is there going to be too mutch noise?
I can use seperate 9V batterys for the arduinos but this takes place in the chasis and costs more.
What size resistor should I use for the vlotage devider? should it be 1000, 10000 or 100000 ohm?
I get the relationshup between R1 and R2 to keep the voltage below 5V but I don't know how to choose R1.
The entire chasis of the bulldoazer is going to be made of metal. Should I ground the chasis?
Sorry for sloppy schematics and my bad English.