Battery Adapter

Most recent answer: 10/22/2007

Q:
I have a battery powered baby swing that takes 4 D batteries. Can I use a 6V plug in adapter to power the swing? If so how do I determine the + or - side of the adapter? thank you Chad
- Chad (age 28)
ontario canada
A:
Briefly put, don't do it! Do not substitute an AC adapter for battery power in products made for babies and small children. There is a serious safety issue here -- if the adapter malfunctions or shorts out, the baby could be injured or killed. There is a limit to how badly awry something can go with just four D-cell batteries, but there is almost no limit when something is plugged into a wall outlet.

You may want to substitute an AC adapter for batteries in another appliation, though. Some adapters have lots of options for different plugs which can be put on either way (I have just such an adapter I got at a popular electronics supply store). One way to find out is to read the manual carefully. Another is to check it with a voltmeter.

If you don’t have the manual or a voltmeter, you can still check it with a battery and a flashlight bulb. By wiring the battery, the AC adapter, and a flashlight bulb (one from a 6V flashlight should do fine for the 6V adapter) in series, you can tell if you’ve got the + and -’s lined up (don’t wire them in parallel -- you’ll short the battery out and could be injured by battery chemicals).

If the adapter is 6V and your battery is 1.5V, then the light bulb will glow visibly brighter with 7.5 V on it (the battery’s + wired to the AC adapter’s - or vice versa) than the 4.5 V you’ll get if you wire it up the other way so the voltages subtract (the battery’s + attached to the AC adapter’s +, for example).

Tom

(published on 10/22/2007)

Follow-Up #1: rechargeable batteries

Q:
Also having a baby swing that devours 4 D-Cell batteries I’d like to propose an alternate solution.

First, Tom’s response regarding things that can go wrong with "alternate power sources" is on target... Here in the USA we have had a sitcom that repeatedly demonstrated that little fact with predictably disasterous but humorous results called "Home Improvement" (Starring Tim Allen among others). It wasn’t all fiction... I’ll repeat: "DON’T DO IT!"

Instead, please realize that the swing is just the tip of the iceburg of battery guzzling toys and baby periphenalia. You’d do far better to invest in a GOOD NiMH battery set and charger, or even a decent Ni-Cd set. Not only will your wallet thank you, but you’ll also be able to sleep at night.
- James (age 30)
Stillwater, MN, USA
A:
good suggestion

mike w


Here, here!
LeeH

(published on 10/22/2007)