A signal of 4 to 20 mA is an example of a?

A signal of 4 to 20 mA is an example of a?

• A. Analog electrical signal
• B. Digital electrical signal
• C. Pulsed signal
• D. Capacitive signal

Answer: (A)

4-20 mA signaling is a continuous current signal used in instrumentation. It is an analog signal because the current can take any value within the 4 to 20 mA range, each value proportional to the measured quantity. This is different from digital signals, which use discrete levels (on/off), and from pulsed signals, which are bursts of activity over time. The 4-20 mA loop is favored for its ability to travel long distances with immunity to voltage drop and to be easily read by controllers, often converted to a voltage inside equipment, while preserving the continuous, proportional nature of the measurement.

4-20 mA signaling is a continuous current signal used in instrumentation. It is an analog signal because the current can take any value within the 4 to 20 mA range, each value proportional to the measured quantity. This is different from digital signals, which use discrete levels (on/off), and from pulsed signals, which are bursts of activity over time. The 4-20 mA loop is favored for its ability to travel long distances with immunity to voltage drop and to be easily read by controllers, often converted to a voltage inside equipment, while preserving the continuous, proportional nature of the measurement.