Help with battery installation

Discussion in 'Electronic Basics' started by Meanie, Jun 23, 2013.

1. MeanieGuest

My wife has an electric yarn spinner which operates from 120v outlet and
converts to a 12v 1.2 amp(max)DC power. Per the manufacturer, amps are
typically running at .5.

I want to provide a power source without the required need for a power
cord. Therefore, the obvious solution is battery power. The confusion
lies with the amps. I know all AAA, AA, C and D size battery outputs are
1.5 v (1.2 running) and each one puts out different amps. As I
understand it, amp output for AAA is roughly 1, AA is 2, C is 4 and D is
8. Therefore, I assume the AA, C and D are not needed due to the higher
amps since I will need at least 8 batteries to achieve 12 volts, unless
I go with a 9 volt plus two AAAs, which seems more logical since a 9v
puts out .5 amps. Anyway, this is the confusing part as what I need and
whether to connect in serial or parallel.

Can anyone provide some enlightenment for my lack of battery knowledge?

Thank you

2. Jasen BettsGuest

it depends how poerable you want it to be and, how much you want to
spend on batteries, and how often you want to change them.

I'd reccomend AA as a starting point and they last much longer than
AAA but cost about the same price.

On the other hand a 12V rechargable tool battery pack might be a
better option, especially if you can borrow one to try out.

3. Bob MastaGuest

A big issue here is how long the device needs to run between
battery charges (or changes). Batteries are rated in
amp-hours. You note that the device normally draws 0.5 A,
so you can find the *approximate* running time for each
battery type by looking up its A-H rating (sometimes
printed on the battery itself, especially for
rechargeables). If it's a 1.5V cell, you'll of course need
8 in series, as you note, but the same A-H rating applies.
Just divide the A-H rating by 0.5 to get hours.

If it needs long running time but doesn't need to be
particularly lightweight, you might consider a 12V sealed

Best regards,

Bob Masta

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4. MeanieGuest

Thank you all for the suggestions. I like the idea of a tool battery.
I'm in the hunt for a 2nd charger for one of my 12v power tools. I plan
to gut the charger and leave the prongs for battery connection. Wire
from the prongs connecting to the required size adapter plug for the
spinner. Therefore, the battery will have a holder and I can recharge it
with my other charger. Sounds good in my head, I hope it works out that way.

5. MeanieGuest

It's already variable speed. I just need the portable power source.