LED for voltage indication

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WbSearch

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Is there a way I can build a simple circuit to illuminate an LED when it
reaches a specified voltage? I monitor the battery voltage on my underwater
strobes during charging to ensure I don't over charge them. I would like to
put an indicator on the batteries so I can tell when they reach the proper
voltage without constantly monitoring them. These units use a very basic
charging system, prior to the "smart chargers", and are sealed units. Thanks
in advance for any help.
 
wbsearch@aol.com (WbSearch) writes:

Is there a way I can build a simple circuit to illuminate an LED when it
reaches a specified voltage? I monitor the battery voltage on my underwater
strobes during charging to ensure I don't over charge them. I would like to
put an indicator on the batteries so I can tell when they reach the proper
voltage without constantly monitoring them. These units use a very basic
charging system, prior to the "smart chargers", and are sealed units. Thanks
in advance for any help.
Click to expand...
Assuming voltage monitoring is a valid indication (this depends on the
type of battery), the simplest accurate indicator would use a voltage
comparator comparing the battery voltage to a zener reference. This
could be used to turn on an LED or even to turn off the charger.

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G'day,
Download http://members.ozemail.com.au/~bobpar/lv-schem.gif which
will probably do what you want. :)


Bob


wbsearch@aol.com (WbSearch) wrote:

Is there a way I can build a simple circuit to illuminate an LED when it
reaches a specified voltage? I monitor the battery voltage on my underwater
strobes during charging to ensure I don't over charge them. I would like to
put an indicator on the batteries so I can tell when they reach the proper
voltage without constantly monitoring them. These units use a very basic
charging system, prior to the "smart chargers", and are sealed units. Thanks
in advance for any help.
Click to expand...

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I forgot to mention... you can buy it as a kit if you don't mind
getting it from Down Under. Go to this long URL for the details:
http://www1.jaycar.com.au/productView.asp?ID=KA1778&CATID=&keywords=voltage+indicator&SPECIAL=&form=KEYWORD&ProdCodeOnly=&Keyword1=xxxxxxxxxx&Keyword2=xxxxxxxxxx&pageNumber=&priceMin=&priceMax=&SUBCATID=

Bob

Hate spam? Go to http://www.bluebottle.com (It's free)
 
"Sam Goldwasser" bravely wrote to "All" (21 Sep 03 18:55:38)
--- on the heady topic of "Re: LED for voltage indication"

A zener may be too temperature sensitive for this application. An
alternative is of course the voltage reference ic. Say something like a
TL439 or various other inexpensive ic's.


SG> From: Sam Goldwasser <sam@saul.cis.upenn.edu>

SG> wbsearch@aol.com (WbSearch) writes:

Is there a way I can build a simple circuit to illuminate an LED when it
reaches a specified voltage? I monitor the battery voltage on my underwater
strobes during charging to ensure I don't over charge them. I would like to
put an indicator on the batteries so I can tell when they reach the proper
voltage without constantly monitoring them. These units use a very basic
charging system, prior to the "smart chargers", and are sealed units. Thanks
in advance for any help.
Click to expand...
SG> Assuming voltage monitoring is a valid indication (this depends on the
SG> type of battery), the simplest accurate indicator would use a voltage
SG> comparator comparing the battery voltage to a zener reference. This
SG> could be used to turn on an LED or even to turn off the charger.


.... I worked hard to attach the electrodes to it.
 
Bob,
Thanks, this is exactly what I'm looking for. Not familiar with Jaycar, but
spent alot of time and money at Dick Smith's when I worked in Sydney a few
years ago. Will be returning there this December and will go to Jaycar and get
a couple of these.
Ron
 
wbsearch@aol.com (WbSearch) wrote:

Bob,
Thanks, this is exactly what I'm looking for. Not familiar with Jaycar, but
spent alot of time and money at Dick Smith's when I worked in Sydney a few
years ago. Will be returning there this December and will go to Jaycar and get
a couple of these.
Ron
Click to expand...

G'day Ron,
I'm pleased this was helpful to you! :)

Cheers,
Bob

Hate spam? Go to http://www.bluebottle.com (It's free)
 
Is Dick Smith still around (as far as electronics is concerned)? I remember
seeing those ads in the USA some years ago, but haven't seen them in awhile.
Also, in the trivia department, I saw a film about Dick Smith that showed
him flying around the world solo in a helicopter. It just goes to show that
if you have money you can travel.
-Ron
(email: replace 'abuse' with 'cyberguy3k')


"WbSearch" <wbsearch@aol.com> wrote:
Bob,
Thanks, this is exactly what I'm looking for. Not familiar with Jaycar,
but
spent alot of time and money at Dick Smith's when I worked in Sydney a few
years ago. Will be returning there this December and will go to Jaycar
and get
a couple of these.
Ron
Click to expand...
 
I think the stores are still around, but not sure as I left Sydney to return to
the US in 1989. Haven't returned since.
 
G'day Ron,
Sure, Dick Smith Electronics is still a big operation. In fact much
bigger than in '89. They have moved into a new warehouse/management
complex to accomodate the expansion of their activities. They did have
an outlet in the USA but closed it down. Lots of people would like
them to return but DSE isn't interested.
Dick himself started out as a humble electronics technician then
did much better as an entrepreneur and got rich. The rest of us are
still humble technicians with old cars and not a chopper in sight. :-(
DSE used to sell that voltage indicator kit too, but discontinued
it because not enough hobbyists were buying it. They are moving
further and further away from the hobbyist/component market while
Jaycar grabs more and more of their old customers.
Just a bit of background info for you. :)

Cheers,
Bob




"Ron" <abuse@hotmail.com> wrote:

Is Dick Smith still around (as far as electronics is concerned)? I remember
seeing those ads in the USA some years ago, but haven't seen them in awhile.
Also, in the trivia department, I saw a film about Dick Smith that showed
him flying around the world solo in a helicopter. It just goes to show that
if you have money you can travel.
-Ron
(email: replace 'abuse' with 'cyberguy3k')


"WbSearch" <wbsearch@aol.com> wrote:
Bob,
Thanks, this is exactly what I'm looking for. Not familiar with Jaycar,
but
spent alot of time and money at Dick Smith's when I worked in Sydney a few
years ago. Will be returning there this December and will go to Jaycar
and get
a couple of these.
Ron
Click to expand...

Hate spam? Go to http://www.bluebottle.com (It's free)
 
Bob,
Thanks for the background. The Dick Smith stroy sounds like radio shack here.
Mostly phones, toys etcf, not much in the way of components. Alot like
HeathKit, too bad.
Ron
 
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