Current and Voltaje inputs

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Please I need know how can I get the values of an
analog current input and an analog voltaje input, I am
using a ADC of two channels but I need the circuit to
convert the current in a voltaje to put it in the
analog input of the ADC, please send me the circuit if
you ca help me.



=====
Alberto Zamora Estrada.
Phone: (506) 220-8279.
Cell: (506) 372-7184
Investigaci

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Buenos dias Alberto,

To be of any real help to you, we need to know the voltage and current
range you expect to measure. We dont' know, you could be dealing with
anything from a megawatt power plant, to microwatt plant power.


One chip that is good for monitoring power supply current is the MAX471 or
MAX472:
http://dbserv.maxim-ic.com/quick_view2.cfm?pdf_num=1108
I have a note on using it to monitor battery current at:
http://www.emesystems.com/BS2misc.htm#battery voltage & RCtime

-- Tracy Allen
Electronically Monitored Ecosystems
http://www.emesystems.com




> Please I need know how can I get the values of an
> analog current input and an analog voltaje input, I am
> using a ADC of two channels but I need the circuit to
> convert the current in a voltaje to put it in the
> analog input of the ADC, please send me the circuit if
> you ca help me.
>=====
> Alberto Zamora Estrada.
> Phone: (506) 220-8279.
> Cell: (506) 372-7184
> Investigacion y Desarrollo.
> I.C.E

Archiver

Thanks Tracy:

If you speak spanish is better for me.

I have to built a general data adquisiton board, it
necesary that it has a general voltaje input (the
voltaje can be 0-10V or 0-20 V) and a gneral current
input (the current can be 0-1 mA or 4-20 mA), I think
that it is not important because I can chose the
range in the software (Delphi), the hardware just have
to support the higher value input, it necesary that
all the inputs will be "optoacopladas".

Thanks, I appreciate your help.



--- Tracy Allen <emesys@c...> escribi

Archiver

> If you speak spanish is better for me.
> I have to built a general data adquisiton board, it
> necesary that it has a general voltaje input (the
> voltaje can be 0-10V or 0-20 V) and a gneral current
> input (the current can be 0-1 mA or 4-20 mA), I think
> that it is not important because I can chose the
> range in the software (Delphi), the hardware just have
> to support the higher value input, it necesary that
> all the inputs will be "optoacopladas".

Hola Alberto,

Tratare en espanol. Creo que hablas ingles mejor que hablo espanol.

Lo que todos los inputs son "optacopladas" es el requisito mas dificil.
Busce los amplificadores "isolados" de
http://www.burr-brown.com
Especialmente el ISO100, que es un diseno optacoplado, o el ISO122, que usa
capacitors para optener el mismo exito.
Cuestan mucho, US$20 a $100 por cada uno, sin embargo se valen mucho a
causa del trababo de contruirlos de partes individuales. Para ver como
funcionan, puede mirar el libro "Art of Electronics". Para transformar el
corriente a voltaje, simplamente se necesita un resistor a traves el input.

-- Tracy Allen
Electronically Monitored Ecosystems
http://www.emesystems.com

Archiver

Muchas Gracias Tracy, leere hacerca de este
amplificador.

Yo estaba pensando en hacer la conversion de corriente
a voltaje por medio de un amplificador operacional
741.

Muchas Gracias por la ayuda brindada.


--- Tracy Allen <emesys@c...> escribi