How it's calculated

Value = EU_min + (Raw − Raw_min) × (EU_max − EU_min) ÷ (Raw_max − Raw_min) or Value = m × Raw + c

Analog input cards convert the field signal to an integer. You then scale it to engineering units in the program, or with the card's built-in scaling where available.

Platform	Typical raw range
Siemens S7-1200/1500, S7-300	0–27648 (nominal range; overrange above)
Allen-Bradley	Set per module (for example 0–32767, or engineering units directly)
Generic 12-bit / 16-bit	0–4095 / 0–65535

For a 4–20 mA input on a Siemens card, 4 mA reads 0 and 20 mA reads 27648. Check the module manual for your exact configuration.