How can I run 3 external hard drives with one power adapter?

Question

I have 3 WD mybook external Hard DriveS......@ w/a 12VDC 1.5A adapter. I would like to run them from a single adapter. I believe they should be parallel but am not certain. My first quess would be a 12VDC 4.5 A adapter with a splitter, but that's a guess. Can anybody help?

Yes. Parallel. It is a bit safer when the three hard drives are connected to the same computer, though. — , Jan 19 '15 at 20:12
Watch the power rating or you may damage the drives if you overload the power. — Maxthon Chan, Jan 19 '15 at 20:27

score 0 · Answer 1 · answered Jan 19 '15 at 22:17

You could use a 12VDC 4.5A adapter and split the outputs; you could possibly go down to 3.5A-4.0A given you do not need triple the available overhead of a single adapter. Also, drives use the bulk of their power on spin-up, when they are running, they use alot less power.

You would wire the separate outputs in parallel.

Also, different adapters react differently to load and voltages. Laptop type power supplies (electronic) put out a fairly even voltage up to max current then the voltage drops off sharply when overloaded. Wall wart (transformer, usually heavy) type adapters usually output a higher voltage under no load with the voltage dropping as load is increased.

Point is, if you get a laptop type adapter, you are more likely to get the proper voltage. These can be found at a place like goodwill for fairly cheap. Just be sure to check the voltage under load (with all the drives on) with a multi-meter; drives can be sensitive to low voltage.

How can I run 3 external hard drives with one power adapter?

1 Answers1