The 4-20mA is a current loop commonly used in industrial instrumentation for transmitting analog signals. 

In contrast, 0-10V represents a voltage signal range.

While both serve as means of transmitting information, including for monitoring purposes, they differ in their electrical characteristics and applications. 

The 4-20mA current loop provides a robust method for long-distance signal transmission, known for its immunity to electrical noise and suitability for harsh environments. In a way, it acts in the circuit like an ammeter, where it is connected in series, and the device or sensor acts as a current flow controller based on its measurement range.

Example:

O2 Sensor with 4-20mA Output and Measurement Range between 0-25% O2.

The current into the loop circuit will be 4mA when O2 is 0%.

The current into the loop circuit will be 20mA when O2 is 25%

For intermediate values, a simple rule of three is sufficient.

On the other hand, the 0-10V voltage signal offers simplicity and compatibility with standard voltage-based devices. In a way, it acts in the circuit like a voltmeter, where it is connected in parallel, and the device or sensor acts as a voltage doser based on its reading range.

Understanding the distinctions between these signal types is essential for designing reliable and efficient monitoring systems across industries.