Would having the receptacle wired "backwards" cause a problem with
battery chargers for cordless tools, etc.?
Both my Milwaukee batteries seem to have become basically unusable due
to their charges lasting a very short time, and I just found out that
the outlet I've been using has the wires reversed.
Have to check the one I've been using for the camera as well, since
that has dies an timely death as well.
And, if anyone has readily accessible any sites for getting new
batteries, I'd appreciate if you'd share (yes, I'm going to do a
google as well).
I thought that was a trick question- to see if we were awake. With 120
polarity reversals/second on the line. :-)
Companies like Batteries Plus can replace the cells, sometimes with new
ones of higher a-h rating for _much_ less than buying new. E.g. 14.4v
P-C pack, 2.1 a-h vice 1.7 (or 1.5) orig, for $35, vice $64 for new.
Connections are spot-welded, pack gets extended test.
No affiliation with Co.
I really like my Milwaukee 18v tools. However, in my experience, the
batteries last 14-20 months max. I date them and save the receipts. If
they fail in less than 12 months, I return them for warranty replacement.
A/C polarity does not affect their life.
Wiring a 110 volt receptacle "backwards" means that the neutral and hot
wires were swapped, and if you're depending on the neutral being neutral
(where it's connected to a metal case for example), a "backward" wired
outlet will have the hot wire connected to the case ... and it becomes a
shock hazard. Your charger doesn't connect anything to any exposed metal
(except plastic) so you shouldn't have any issues with that.
With regard to your batteries ... I am assuming your charger shows charge
complete, and that you get a very short run time from them (as compared to a
new battery). It is a pretty good guess that either one or more cells in the
battery pack have shorted, or have been charge/discharge cycled sufficiently
to dry out the electrolyte. In either case the batteries (or just the cell
pack inside) need replaced. I'm also assuming you have more than one
charger???? Could be a charger problem; easy to borrow another charger and
see if you get a better charge on your battery with the different charger.
Now ... if you had told me your battery wouldn't accept a charge ... that's
a whole 'nother thing. THAT is an easy fix ... you jumper two batteries
(your bad one and a freshly charged one) positive to positive, negative to
negative for about 1 minute, then pop the "bad" one back into the charger.
If it doesn't accept a charge, jump it again ... but for two minutes. Once
it takes a charge you're in good shape ... just remember to charge the
"booster" battery when you're done as well. This is caused by leaving the
battery on a tool and leaving the tool on (happens with regularity with one
of our 18-volt drills being dumped into the big red bag and the switch
getting shoved despite the trigger lock mechanism. You discharge the battery
below the level that the charger registers as "battery present - start
charge cycle" ... and by jumping the battery with a fully charged one, you
put enough current through to raise the voltage above the "start charge
Hope this helps,
That would be a safety issue (to you) in that any fuse in the charger should
be on the hot lead and it should be carefully layed-out so that it cannot
contact anything that might make the voltage present on a user-touchable
surface. As for the battery charging circuitry, it should be OK because the
AC comes into (usually after a step-down transformer) a full-wave bridge
rectifier which changes the voltage to something approximating DC (it has
ripple at this point which they filter out (smooth) with a capacitor). The
rectifier doesn't care as to which AC lead is connected to which side, it'll
work the same either way.
Thanx for the responses.
I didn't really think polarity was related to my batteries suddenly
losing potency, but it was a recent discovery in my "new" house and I
know a few things are sensitive to polarity, so I threw out the
question onto the wRECk..
The batteries are probably past their prime, in spite of not a whole
lot of use. They're the 18v Milwaukee, NiMh I believe, and probably
about 3 years old.
3 years is the average.
Keep in mind also that larger voltage batteries have more cells packed
inside the battery case and heat is an enemy to these cells. Because there
are many more cells in an 18 volt battery vs. a 9.6 or 12 volt battery you
have more cells insulating the inner cells during heavy use and recharging.
It is an inherent fact that the more cells a battery has and the way they
are packaged in the battery pack the shorter life span they will have when
compared to the lesser voltage ones. Basically, what you gain in longer run
times and power you loose in life expectancy with all things being equal.
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