I was reading about "Canopus-Analog Voltage & Current Isolators". When voltage is applied between load terminals, it will generate some current. Can someone explain what do they mean by isolation, here?
I guess you are talking about this or similar device.
When voltage is applied between load terminals, it will generate some current.
If you want to read sensor values (commonly 0-10V signals) over a long distance, a voltage signal is often undesired, because of the voltage drop along the wires and noise injected.
A current signal is much better in this situation, as the resistance of the wire wouldn't influence the current, given that the current source is able to drive it (minor concern). Usually the 0-10V signal is mapped to a 4-20mA current. The minimum current of 4mA, instead of 0mA, is used to reduce the effect of noise injection on small signals.
Can someone explain what do they mean by isolation, here?
Isolation, in this context, means that the two sides of the converter share no common potential. This is important in eg. industrial applications, as ground potential might be different across a large building and this would cause a small additional current in any non isolated circuit.