Hello,
I have been using a water irrigation system I created with your help for 3 (almost) successful times.
The scheme is reported in the closed discussion here
Now I was thinking of using the same circuit to power an additional pump through the same battery.
For simplicity I do not want to create a symmetric circuit and activate the pumps independently.
I want to use the same one with pumps working at the same time.
Therefore, I was thinking of adding the second pump in parallel with the first one.
In the photo below, you can see at columns 8-10 the green wires (positive and negative of the pump) I cut to clamp the 3-way connectors. I was thinking that now I can connect the positive wires of the 2 pump to the 3-way connector connected to the positive pole and vice-versa for the negative ones.
Is that correct? is this considered in parallel?
Can I do the same thing for the battery that powers my Arduino? I want to increase the capacity leaving the same voltage (from 3AAA to 6 AAA). If I cut the black and red wires you see attached to the battery slots, can I use the same system for attaching a second battery slot?
The diode and capacitor need to be on each motor terminals, or as close as possible to each motor. They are there to limit the electrical noise generated by each motor.
Ok, I got it.
I was hoping that the capacitor and diode were enough for the motors.
Since it is a general schematic without any reference to the 12V motor, I have no idea how they compute 1uF for the capacitor .
Thanks
The cap value is likely an error. It is about 100 times to big. The cap is there to short out the noise generated by the armature brushes. The diode is there to short out the reverse voltage pulse when the current to the motor is momentarily stopped.
Too big means that it is not efficient in reducing the noise or not effective?
If the value is too large, should not be working with more motors?
An oscilloscope would be the only solution to check that?
Too big. both electrically and physically means it will act more as an antenna an radiate the noise to your other components. Too big means it will absorb the power pulses you use to regulate the speed of your motor rather than the motor seeing the pulses. The capacitor will absorb current at the same time as the inductance of your motor rejects the current pulse.
