The passive galvanic isolator is a device which separates electrically the input from the output signal.
Both signals are continuous current ones, in the range from 4mA to 20mA.
It is used in such cases when it is necessary to separate galvanically current sources (transmitters, DACs, etc.) from the input of measurement devices, controllers, etc.
PRG2 does not need external power supply
(the energy for transformation is derived from the energy of the input signal in the range from 0 to about 1mA.)