Instructables

Single AC Adapter for multiple devices?

Just wondering if there's any downside to re-wiring an AC adapter to run multiple devices. I have 6 of these wall warts near my TV for the following

- router
- usb hub
- phone charger
- harmony one charger
- clock
- PS3 bluetooth/IR converter

Most of these run on either 6,9 or 12V. I would be so much cleaner if I can rewire (or splice) a couple of AC adapters to have like two or more outputs.

Is there any downside to this? Thanks

lewisb422 years ago
It's dicey. You have to make sure that the total current consumed by the devices sharing one wall wart is no more than its current rating. Even then I'd put a fuse with the same (or slightly less) current rating as the adapter in series with its hot lead.

Be especially careful if you plan to turn all the devices on at the same time, say if you were turning a TV, video game console, and surround sound system on all at once (maybe from a universal remote). The power spikes at turn-on could easily surpass their nominal current ratings.
ketchup318 (author)  lewisb422 years ago
lewisb42: dicey... well, that's why i'm asking around before I zap all my electronics. Although the input voltage veries between 6-12V, the total current draw isn't that much, according to my Kill-A-Watt. If I remember correctly, it all was under 2A. But an inline fuse that matched the adapter rating is a good idea.
I've never used a Kill-A-Watt before, but a quick look at the specs suggests it measures AC amps going into the adapter. The actual DC amps supplied by the adapter could easily be higher due to the way step-down transformers work (they lower the AC voltage and increase the AC amperage it can supply, which is then converted to DC). Again, I'd look at the DC amperage draws of the devices you're connecting to it and compare that to the DC amperage rating of the wall-wart (which should be printed on the brick).

That said, I see a Kill-A-Watt in my future.