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+--- Thread: 2wire 4-20ma water sensor (/showthread.php?tid=343)
2wire 4-20ma water sensor - ajandali - 07-11-2021
Hi, I want to know if I can use KC868-COLB Logical Controller to measure water level using the 2wire 4-20ma water sensor. Picture below.
RE: 2wire 4-20ma water sensor - admin - 07-12-2021
KC868-COL/COLB/COLB-Mini support use analog sensor that 0-5V output, if you already have 4-20mA sensor. you can use a 250 Ohm resistance connect with signal input port and GND to convert.
To convert a mA analog input signal to voltage you need to attach a inline resistor. The size of your resistor will determine the output range of your voltage.
Resistor Calculations are as follows:
Using ohms law V = R(I) (Voltage = Resistance * Current)
If we were to scale a 4-20mA to 1-5V
For the 0 Value: .004 Amps * 250 ohms = 1 Volt
For the Max Value: .20 Amps * 250 ohms = 5 Volts