4–20 mA signal calculator

4 mA is the bottom of the range and 20 mA the top, linear in between. A current below about 3.8 mA or above 20.5 mA usually means a broken wire, a short circuit or a faulty transmitter.

Result

Percent of range50 %

How it is calculated

Value = from + (I − 4) / 16 × (to − from). Current = 4 + 16 × (value − from) / (to − from).

Reference only. The maker's manual and class rules take priority.

Reference table

mA	Percent of range	0–10 bar
4	0 %	0.00 bar
6	12 %	1.25 bar
8	25 %	2.50 bar
10	38 %	3.75 bar
12	50 %	5.00 bar
14	62 %	6.25 bar
16	75 %	7.50 bar
18	88 %	8.75 bar
20	100 %	10.00 bar

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