# How much power will a series of linear actuators need?

I have 36 linear actuators and an Arduino Uno. All the input voltages are 12V DC. The linear actuators have a current draw of 0.2 amperes. How would I find out what power supply I need?

• The power supply needs to supply the voltage each device requires at the sum of all the currents. Commented Feb 5, 2023 at 5:33

(Edit: this was originally based on a misreading of the post - I thought it was 2A per actuator, not 0.2A. I've updated the post to reflect the lower current.)

You need a 12V supply that can source enough current to cover all of the devices that you need to operate. If you have 36 actuators at 0.2A each, that's 7.2A. You can effectively ignore the power draw of the Arduino here, since it's so much less than the rest of the loads.

If there's any possibility that all actuators will be driven at once, you'll ideally want to pick a supply with a maximum current spec of 8A or more just to give yourself a 10% overhead.

That's almost 1000W. It might work out cheaper to use multiple supplies instead of one big one. You could split the actuators into two groups of 18, with two 12V 40A supplies, or four groups of 9 actuators, with four 12V 20A supplies. In such a setup you should tie the power supply output grounds together, with separate positive lines for each group. (Edit: splitting supplies is not that useful for 0.2A per actuator)

If you can guarantee a maximum number of actuators that will be operated (i.e. moved) at the same time, you can likely use a smaller power supply that is rated to be able to supply to the sum of the required currents for that number of actuators, plus a 10% overhead. For example, if you know that you'll only ever be moving half of them at once, you could use an 12V 4A power supply. You should also include a fuse to ensure that you protect the supply from overcurrent.

• how would it be 2amps per actuators when the maximum is .2 amps Commented Feb 5, 2023 at 17:47
• Sorry, I must've misread your post as "2 amps" not "0.2 amps"! In which case divide all of these by 10. Commented Feb 5, 2023 at 17:48
• in that case is it possible to use a 12v 40 amp power supply to power all the actuators Commented Feb 5, 2023 at 17:50
• I've updated the answer. 12V 8A should be fine, although I'd probably just go for 12V 10A because there'll be more supplies available at that "round" current value, and it gives you a little extra headroom. Commented Feb 5, 2023 at 17:52