Re: I am about to add an LED to a charger but need further opinions.

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#470

From: Ol' Duffer
Date: Wed, 15 Mar 2006 04:18

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In article <1142391196.601886.28100@i39g2000cwa.googlegroups.com>, 
alitonto@hotmail.com says...
> I have seen some chargers that have the dropping resistor and LED in
> series  with each other and then this combination is in parallel with
> another resistor of lower ohms which goes to the battery pack

I assume your reason for considering this is to get a visual
indication that there is actually current flowing into the
battery.  A reasonable thing to want, but...

Some of the makers who have done this have had trouble with
blowing out the LED's.  Consider what happens when you plug
in a dead battery, or maybe even worse a bad one that happens
to be shorted...

If you have the room and can tolerate more parts, maybe
consider something like using the b-e junction of a power
transistor that can shrug off the worst case current and drive
the LED with a resistor off the collector.

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From: Ol' Duffer <DontSend@MeSpam.net>
Newsgroups: sci.electronics.repair,aus.electronics
Subject: Re: I am about to add an LED to a charger but need further opinions.
Date: Tue, 14 Mar 2006 23:18:56 -0500
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