Hello to all,
I have an application where I have one transmitter 4-20 mA (loop powered) and I need to connect its current output to two AI channels.
The transmitter is Siemens pressure transducer and its resistance is according to the manual around 650 ohm. AI card is SM331 and input resistance is about 250 ohm. Loop is 2-wire (2DMU) so the transmitter is powered by the AI channel. Right now, I need to use the same current signal to the other SM331 on another PLC.
In order to do so, I decided to use Siemens loop powered passive isolator with specification that its load at max output current is 400 ohm. Of course, other channel must be passive (4DMU). I'm worry that loop load will cause problems.
There is also an option to use this separator: http://www.loreme.fr/fichtech/CAL25ig_eng.pdf
I think higher resistance (load) of galvanic separator is better.
I wonder if this is correct way to solve this? How you solve similar problems (one transmitter in the field to two channels)?
Thank you
I have an application where I have one transmitter 4-20 mA (loop powered) and I need to connect its current output to two AI channels.
The transmitter is Siemens pressure transducer and its resistance is according to the manual around 650 ohm. AI card is SM331 and input resistance is about 250 ohm. Loop is 2-wire (2DMU) so the transmitter is powered by the AI channel. Right now, I need to use the same current signal to the other SM331 on another PLC.
In order to do so, I decided to use Siemens loop powered passive isolator with specification that its load at max output current is 400 ohm. Of course, other channel must be passive (4DMU). I'm worry that loop load will cause problems.
There is also an option to use this separator: http://www.loreme.fr/fichtech/CAL25ig_eng.pdf
I think higher resistance (load) of galvanic separator is better.
I wonder if this is correct way to solve this? How you solve similar problems (one transmitter in the field to two channels)?
Thank you
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