Maker Pro
Maker Pro

Need help connecting vibrating motors

Hello. Let's me start by saying I know nothing about electronics. I do have a fairly simple project though.

I am looking to connect 7 of these motors https://www.adafruit.com/products/1201.

All 7 will be running at a time but only for about 10 minutes or so. Periodically.

I have two problems that I need help with ...

1) What power source should I connect these motors to? I would like 3v because the vibration is good for my application. Also, if you recommend a battery I would need it to last a decent amount of time. Like I said all 7 motors will be running at once for about 10 min, maybe 20 times a day.

2) I need to connect all these motors to some sort of switch that I can turn on and off. All the motors should be connected that that one switch.

Any help would be greatly appreciated. Like I said I know nothing but I'm fairly confident this is a simple project.
 
We need to know how much current each motor draws when driven with 3V. Do you have a power supply and multimeter?
 

Harald Kapp

Moderator
Moderator
1)
The website says:
5V current draw: 100mA, 4V current draw: 80mA, 3V current draw: 60mA, 2V current draw: 40mA
(Underline by me)
Current requirement: 7 motors -> 7*60 mA = 420 mA
Uptime: 20 * 10 minutes per day = 200 minutes = 3.35 hours per day
Energy requirement: 420 mA * 3.35 hours per day = 1.4 Ah per day (or 1400 mAh per day)
Lifetime of the battery: capacity = xx Ah (xx to be defined by you or taken from the battery's datasheet if you already have a battery) -> lifetime = xx Ah / (1.4 Ah per day) in days.
Or, given the lifetime as yy days: capacity = 1.4 Ah per day * lifetime (days)

2)
Any single pole single throw (SPST) switch will do as long as it is rated for 420 mA or more. Connect all the red wires of the motors together, connect also all the blue wires together. Connect the blue wires to battery '-', connect the red wires to one contact of the switch. Connect the other contact of the switch to battery '+'.
It probably doesn't matter which color goes to which contact or battery pole, it is simply conventional to use blue for '-' and red for '+'.

Be aware that this kind of vibrating motor is typically designed for short alarms. Running the motor(s) for an extended period of time (10 minutes are long compared to the typical few seconds when used as an alarm) may cause overheating and early failure of the motor(s).
 
I completely failed to notice the link in the O.P. I don't like Adafruit so it may have been due to a subconscious aversion.

Harald's got the energy budget worked out and the minimum battery supply that would get you through a day would be two AA alkaline cells but it would be more economical to use larger batteries or a plug in power supply.
 
Last edited:
Top