Controlling a 12V 3A linear actuator

I'm new to using an Arduino and electronics in general. I am trying to control the movement of a linear actuator that, ideally, uses 12V and 3A but obviously my Arduino can only output 5V and i believe 0.8A. does anyone know how this would be done? And as i said i am new to this kind of stuff so it would be nice if you were to either dumb it down a bit for me or to link me to a website or video.

If you need any specific info then this is the stuff i'm using:

actuator: https://www.amazon.co.uk/gp/product/B0171NTN8S/ref=ppx_yo_dt_b_asin_title_o01_s01?ie=UTF8&psc=1

relay board: https://www.amazon.co.uk/gp/product/B07GXC4FGP/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

and i'm using an Arduino Uno R3

thanks in advance!

obviously my Arduino can only output 5V and i believe 0.8A.

The Arduino 5V output must not be used for motors, servos, etc. It is intended at most for a couple of low power sensors, LEDs etc.

For that actuator it is best to use a modern H-bridge motor driver, capable of at least 8A peak current draw (the start/stall current is much higher than the running current).

I use this one in parallel mode for similar actuators.

The 12V power supply must also be able to briefly (e.g. for 15 milliseconds) supply the start/stall current, so plan on 7-8 A there as well. Some 12V/5A power bricks simply shut down if overloaded even for a short time.

Finally, make sure motor driver wiring is secure, and don't change connections with the power on. Motor drivers can instantly be destroyed by loose wires.

Your relays are single pole double throw (SPDT) and the pair can be used to control your actuator when you power it with 12 volts.

The two wires from the actuator connect to the common terminals of the relays. One wire to each relay.

The 12 volt + is connected to the NC terminal on relay number 1 and to the NO terminal on the second relay.

The 12 volt - is connected to the NC terminal on relay number 1 and to the NO terminal on relay number 2.

When 12 volt power is applied to the relays, the actuator will move to the end of it's movement if nothing is done to control the relays.

Your Arduino program will be able to turn off the power to the actuator by turning on just ONE of the relays, so on startup, you need to ensure one relay is on and one is off.

Forward and reverse are controlled by controlling both relays at the same time.

Since there is no way to know the actual position of the actuator and no harm will be done by running it clear to the end of movement, I suggest you program the starting point to let the actuator run to an end and then turn one relay off to stop the power.

If your project does not care about positioning, then you are all set to go.

If you do care, then you need to calibrate the number of milliseconds of power with the actual movement of the actuator and always count the milliseconds no matter which which direction the actuator moves.

Does that help any?

Paul

There are two ways to connect 2 SPDT relays to control a motor - the one with common terminals
to the motor leads allows free-wheel diodes to be used, and prevents any risk of shoot-through.

Don't fall into the trap of connecting commons to the supply rails, ie use this topology:

Paul_KD7HB:
The 12 volt + is connected to the NC terminal on relay number 1 and to the NO terminal on the second relay.

The 12 volt - is connected to the NC terminal on relay number 1 and to the NO terminal on relay number 2.

So what wires do i connect to my Arduino? My relay board has a ground, VCC (or VOC it's hard to read) and 2 input connections. I assume i have the 2 inputs connected to my Arduino and then the ground and VCC are also connected to my power supply? Also what power supply should i use? is there a specific make or should i just use any power supply with the right voltage and amperage, expose the bare wires and connect it to the relay?