History of 3-15 psi, 10-50 mA, and 4-20 mA signals
Study about the history of 4-20 mA signals used in the industrial instrumentation. Other signals are 3-15 psi, and 10-50 mA
IEC labelling for Resistors Color Code
The IEC also defines how manufacturers should mark the values of resistors and capacitors in the standard called IEC 60062. The colours used on fixed leaded resistors are shown below:…
Fieldbus vs 4-20mA
The sensors and actuators that are connected to the inputs and outputs (IO) of a Programmable Controller or PLC are normally mounted in the plant. Therefore the IO connections of…
Smart Transmitter Calibration Tutorial Part 1
Calibration can be carried out using a handheld communicator in the field, a laptop on the bench in the workshop, or from intelligent device management (IDM) software as part of…
Smart Transmitter Calibration Tutorial Part 2
Range Setting (Re-range)Â Range setting (re-ranging) refers to setting the scale for the 4 mA and 20 mA points. This scale is usually referred to as "calibrated range" or "calibration…
Smart Transmitter Calibration Tutorial Part 3
Transmitter Output Current Trim (Analog Trim) It is rare for the analog output current circuitry of a 4-20 mA transmitter to drift. However, should the analog output current be incorrect,…
Instrumentation Engineer’s Calibration Mistakes
Instrumentation Engineer's Calibration Mistakes Error When Attempting to Reverse the Range In some applications, particularly DP level, it is necessary to reverse the range such that the LRV > URV.…
Important Terms in Calibration
The term "calibration" in the context of smart/intelligent transmitters is often misunderstood. The information provided here serves to explain the difference between sensor trim, range setting, and current trim. Plants…
Formula to Calculate Process Variable from 4-20mA
How to Calculate Process Variable from 4-20mA current loop output of a field transmitter. Check the formula to find out Process variable (PV). Calculate Process Variable from 4-20mA Formula…
Formula to Calculate 4-20 mA from Process Variable
How to Calculate 4-20mA current loop from Process Variable value of a field transmitter. Check the formula to find out equivalent 4-20mA signal from Process Variable. Calculate 4-20mA from Process Variable Formula :…
