We have a signal of 4-20mA that goes about 100m far.
In the cabinet there is the 4-20mA source, and 100m further in the field there is a proportional valve that is controlled by this signal.
Now we want to check back what the exact signal is at the valve (to detect disturbances or irregularities).
We decided to loop the signal inside the cabinet through a 4-20mA analog input of the plc. As this is a current signal, I suppose that any disturbance seen at the position 100m in the field would also be seen at the analog input in the cabinet? Or is this not always correct?
In the cabinet there is the 4-20mA source, and 100m further in the field there is a proportional valve that is controlled by this signal.
Now we want to check back what the exact signal is at the valve (to detect disturbances or irregularities).
We decided to loop the signal inside the cabinet through a 4-20mA analog input of the plc. As this is a current signal, I suppose that any disturbance seen at the position 100m in the field would also be seen at the analog input in the cabinet? Or is this not always correct?