I have built a 12v rover - designed to be fully autonomous with a 12v deep cell marine battery as its only power source.
It uses the following components:
1. [Raspberry Pi3 through a power converter] 2. [Sainsmart 16 Channel Relay Board connected to the PI to control motors.] 3. [LED Monitor (Draws 2A at 12V)] 4. Four 60 Watt Hobby Motors
It works great. I can write the code and drive it around the yard.
However - when the motors are engaged, the LED Monitor shuts off and comes back on again - as if it lost power. The PI seems to be unaffected and everything works fine - except for the momentary rebooting of the monitor.
A voltage meter shows 12.5 at the battery - drops to 11.9 when the motors are engaged, and stays at 11.9 until the motors stop and then goes back to 12.5.
My guess is that when the motors are engaged, it draws a large amount of current, more than the battery can provide, and causes the monitor to reboot. My guess is that this is not good for the components long term.
My question is - can I somehow isolate the motors from the circuit, even though they use the same power supply - so that the momentary start-up draw does not affect the rest of the components? What is the proper way to wire such a circuit?