A
alcuemar
- Jan 1, 1970
- 0
Dear Friends,
I have read today that there is one possibility to isolate the 4-20mA
input signal using the IL300 octocoupler, I have read the application
note 54 from siemes but i have not too much clear the functioning of
the design.
http://crio.mib.infn.it/wig/electro...n/Accoppiatori Ottici/IL300 per industria.pdf
My design require 8 analog inputs from 4-20mA, with the possibility of
to detect the broken sensor or short-circuit sensor, and out of range
sensor, so the option to do that without isolation is to put simple
shunt resistor for 220 ohm, 4mA = 0.88V, and 20mA=4.4V, so we can
detect the out of range easitly, the short-circuit will be 0V, ... and
the broken sensor will be 0 too.
How to do the same using the IL300 linear octocoupler, in the
application note 54 page 11, they equation to join the input and
output is Vo/IL=(R3/R4)*R5*K3, what is the value for K3??.
I have some doubt about how to use this design.
If someone has make something similar I will appreciate the help.
Thanks in advance.
Alberto
I have read today that there is one possibility to isolate the 4-20mA
input signal using the IL300 octocoupler, I have read the application
note 54 from siemes but i have not too much clear the functioning of
the design.
http://crio.mib.infn.it/wig/electro...n/Accoppiatori Ottici/IL300 per industria.pdf
My design require 8 analog inputs from 4-20mA, with the possibility of
to detect the broken sensor or short-circuit sensor, and out of range
sensor, so the option to do that without isolation is to put simple
shunt resistor for 220 ohm, 4mA = 0.88V, and 20mA=4.4V, so we can
detect the out of range easitly, the short-circuit will be 0V, ... and
the broken sensor will be 0 too.
How to do the same using the IL300 linear octocoupler, in the
application note 54 page 11, they equation to join the input and
output is Vo/IL=(R3/R4)*R5*K3, what is the value for K3??.
I have some doubt about how to use this design.
If someone has make something similar I will appreciate the help.
Thanks in advance.
Alberto