# Can I hook up more than one device per terminal on a power supply?

First post!

My question is straightforward, and NOT a duplicate post. This is meat & potatoes here, less on theory, more on practical application. I know you are all more knowledgeable than I am. Hoping for a quick answer (which doesn't theorize about Johnny or his appetite for apples).

I'm thinking of buying a non-PC power supply to do some stuff with LED light strips. I have read some about series and parallel connection options. I'm good as far as that goes. I can follow pictures/procedures. Here's what I have NOT found an answer to searching all across the web. My project might involve other devices and so my question is:

The power supply is 600W 12V 50A. This will exceed my total need. The question has to do with the number of terminals on the power supply itself. Here's a picture of it:

You'll notice it has 3 terminals +/- on the back.

At long last, my question: WHAT IF I HAVE MORE THAN THREE DEVICES?

As long as each and every device is rated for 12V (USA) and the total will not exceed maybe 400-450 watts tops (honestly, not sure how many amps will flow, but definitely under 50), can I rig up more than one device on each of the 3 terminals?

In my mind, I'm thinking I could strip wires and then just stack them on top of one another, considering and then deliberately choosing which terminal to use to try to "balance the load" <--- used here in a logistical sense, not just in terms of numbers of devices to be connected, but also in terms of "equal" power supply per terminal.

Essentially, I want to eliminate wall warts and power bricks. Simple. One plug in the wall, grounded, for everything. Can I do it?

Assuming ALL the components/devices are 12V, don't add up to 600W and won't push anywhere near 50 amps?

Let's say I have 7 or 8 devices, not necessarily just LED light strips. Can I do it? That's all I want to know. Additionally, does it help to try to evenly distribute the total across just 3 terminals?

If I CAN'T do it, can anyone tell me how to achieve my desired result? I've already considered the potential downsides if the power supply fails/cuts out or alternately decides to fry everything. To me, it's worth the risk.

I want to eliminate wall warts. I may buy a power supply so I can hook all sorts of stuff into it. Gentlemen, how should I proceed? No theory; just practice, please. I'm looking for confirmation, yes or no, that I can do what I want. If not, a pointer in the right direction, and thanks for reading my long-winded question!

• I'm intrigued by the idea of a non-PC power supply. Presumably when you plug it in, it starts bad-mouthing minorities and making edgy jokes. – Neil_UK Jan 21 '19 at 20:04
• @Neil_UK I doubt that will choke off the wall warts. – Indraneel Jan 22 '19 at 6:03

The only reason there are three pairs of screw terminals is due to the high amperage output of the power supply. If you were to try to carry 50 amps over a single wire, it would need to be very large diameter and you would not be able to safely connect to a single screw terminal of the size used. If you check with an ohmmeter, with the power off, you will discover that all three V+ terminals are connected together internally (same with the V-).

If you wanted to have a single load taking all 50 amps, you could connect it with three pairs of wires, each large enough for at least 16.7 amps.

Similarly, if you had many loads to share the amperage, totally less than or equal to 50 amps, you could connect many wires to the terminals. If you have only a few pairs, you could connect them directly to the screw terminals. If you have more, you could run few large wires from the power supply to a distribution assembly to branch out to all of your loads. This could be terminal strips, buss bars or even a PCB. Take a look at the answer from @xakepp35 for ideas. (I believe it was downvoted because it did not actually answer your question of why.)

By the way, the reason there are three pairs is the same as why an ATX power supply has multiple wires of the same color (voltage) going to the main connector: too much amperage for single wires and too much amperage for single connector pins.

Can I rig up more than one device on each of the 3 terminals?

Use the force, Luke:

Then something like this (better):

After you done, you can obtain nice dish of tasty ferrules:

Then put other ends of wires to ferrules (each wire to own ferrule) and crimp'em:

Put your ferrules to the terminal strip:

Now you have distributed single high current terminal to multiple low-current ones. Solder couple of wires to a led strip, crimp other ends, and connect that to your newly made and beautiful terminal strip socket:

And important: you have socked-type of connectors at the supply side. And a plug-type of connectors at consumer side. Everything is insulated, safe, and easily serviceable.

## Caution.

But use wisely, with care. Follow the amperage ratings (not to oxidate and burn connections): Excessive current will force contact to overheat:

So Do your research and google specs in first place. Typically, try not to exceed 10-15A currents per one terminal:

That gives 15A * 12V = 180Watt safe maximum power transfer per one terminal of your supply.

You have 50A? Okay, load it up to 45A. Take 3 18awg wires, and put it inside one ring terminal. So you can connect no more that 3 devices to single terminal, and each device should not exceed 10 amps(wire limit, terminal strip limit), and 5 amps if all three are connected(5+5+5=15 - power supply terminal limit). You can connect 9 led strips rated 12V 5A (60W each)