Question
Do you have an One Chip solution to Transform an 0-20mA Signal to an isolated
0-5V Signal (or something similar)? So it's a Sensor we want to read out with a
voltage Module for further use. The Isolation is very important because we have
grounding issues. Supply Voltage is 24V DC on the Voltage Module, the Sensor
gets his supply from his parent device, that has 230V AC supply without a
ground.
Answer
Before making a recommendation I want to make sure I understand how the
isolation should be applied.
We have Isolated Input modules and Isolated Output modules and a 3-port module:
- An isolated Input module generally has the module power supply on the output
side , meaning the Input signal is isolated from the power supply as well as
being isolated from the output signal.
- An isolated Output module generally has the module power supply on the Input
side , meaning the Output signal is isolated from the power supply as well as
being isolated from the Input signal.
- A 3-port Isolator has both the Input and Output Isolated from the module
power supply as well as having Isolation from the Input to the Output.
You mentioned that you want to measure a 0mA to 20mA signal and provide an
Isolated 0V to 5V signal. Based on your description you would need either a
3-port Isolator (like the AD210) or an isolated voltage Output module (like a
7B22).
We need to know if the power supply that is intended to power the ADI module is
on the 0mA to 20mA side or if it is on the 0V to 5V side of the measurements
being made. E.g. in the case of an AD202, the input is Isolated from the output
and module power supply, however the output signal is not Isolated from the
module power supply.