Hi! I recently purchased the ‘Mute Sounds Mini Submersible Pump DC 3V-5V’ for my arduino project.
I was wondering if I would be able to use the pump directly with my arduino board (input voltage of 5V) or if I’ll be required to use a separate power supply to power the pump, as it draws a large amount of current.
If I’m required to use a separate power supply, would you suggest using a relay module/board to power the water pump? And if so, do I power it with an external 5V as the pump requires DC 3-5V or do you suggest I use a lower voltage?
You’re right, any DC supply within the rated voltage should do the trick, although I’d be careful running one of these motors off a 9VDC source as it may burn it out if there exists any load or continuously used for a short period of time. Also, the maximum power output of the Arduino Uno is 5VDC at 40mA which is 0.2W, which falls short of the 0.36W required by this pump at full load running at 5VDC. The quickest and least expensive fix to get around this is to throw in a H-Bridge or motor driver to isolate the Arduino’s outputs from the power to your motor such as that which I’ve linked below (it has pre-soldered headers so it should be easier to wire up or insert into a breadboard, although it will be a tight fit). QUOTE FROM LINK BELOW.
Hi Ril
Jaden is right, the Arduino will not run the pump directly but an H bridge motor controller is a bit of an overkill.
About all you need is a Mosfet switch. One already mounted and set up is SKU: CEO4538 from Core. It is very small and clearly marked.
Connect pump positive to power supply positive (5V).
Connect pump negative to Mosfet “D” (Drain).
Connect power supply negative to Mosfet “S” (Source) also to Arduino Ground.
Connect Arduino output pin to Mosfet “G” (Gate).
To avoid Mosfet damage connect a fast (Schottky) diode across the pump, Cathode to Positive side and Anode to negative side.
That’s it, any other required components are already on the little board.
Cheers Bob
Excellent suggestions from Bob and Jaden!
Unfortunately, Core doesn’t have stock of the Freetronics modules Bob suggested at the moment.
To get the parts ASAP I would make up the cart to have
Making the circuit to match the schematic on the module could be done on a breadboard as the motor uses a low amount of power(<<5W which is what is considered a ‘typical maximum power’ for a breadboard).
I have set up my circuit according to this schematic, however my water pump is not working
Could you please have a look at my circuit?
I have tested my output from the Atmega microcontroller pin on my breadboard and it is definitely working and the water pump is also working. So I believe there may be an issue with the MOSFET.
Hi
Check continuity along the groups of earth sockets on that bread board. Some (I have one) of these have the groups of 5 sockets in a batch of 2or 3connected then a break between “sets” of socket groups. There is no continuity from one end to the other.You have to link groups to achieve this. If this sis the case your -ve connection is not made properly.
Where is the schottky diode across the pump motor? The high (many times the supply) reverse voltage generated across the motor at switch off can, and usually does destroy the mosfet.
Cheers Bob
Edit: Connect all of the -ve or ground connections to the same group of 5 socket points. That will eliminate any non continuity problem.
Yes I can see what has happened now. I suggested this as I have a couple and they are pretty convenient and appear to switch solidly with a 5V gate signal. I would not go below the 1k series input resistor though as the Arduino has not got a great drive capability and might have trouble charging and discharging the gate capacitor. For high currents where switching time is important to keep heat generation down I tend to use an interface with a couple of transistors or there are dedicated mosfet driver chips around to provide the charge / discharge current. This allows the use of a low value series resistor thus a shorter switching time.
Cheers Bob
