Instrument Percent of Span Error
An important part of performing instrument calibration is determining the extent of an instrument’s error. Error is usually measured in percent of span. Instrument Percent of Span Error Calculate the...
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Instrumentation control engineering formulas used in industrial control systems and field instruments like 4-20mA and 3-15 PSI conversions.
How to do 4-20mA Conversions Easily
Generally it is possible to generate a “custom” linear equation in the form of y = mx + b for any linear responding instrument relating input directly to output, a more general...
Example of 3-15 psi to 4-20mA Conversion
A current-to-pressure transducer is used to convert a 4-20 mA electronic signal into a 3-15 PSI pneumatic signal. This particular transducer is configured for reverse action instead of direct, meaning...
PLC Raw Count Calculation for Pressure Transmitter
Every instrument has at least one input and at least one output. For instruments responding linearly, the correspondence between input and output is proportional: PLC Raw Count Calculation A practical...
4-20mA Formulas and Examples
4-20 mA transmitter current output can be converted to the voltage within a specified range, from 0 to a maximal amplitude Vmax, as shown in the following picture: 4-20mA Formulas Calling I...
PLC Analog Input Conversion Formula
For any unit conversion on any PLC, you can use four function math with the following for PLC Analog Input Conversion Formula, which assumes integer math, as follows : PLC...
PLC Problems Troubleshooting
Troubleshooting PLCs can be started by checking the healthiness status of CPU, I/O Modules, Fuse Blow-out and different PLC Failure reasons including wiring, field transmitters healthiness status or transmitter configuration,...
PLC Analog Input Scaling
An Allen-Bradley SLC500 programmable logic controller (PLC) uses a 16-bit analog-to-digital converter ( in its model 1746-NI4 ) in analog input card to convert 4-20 mA signals into digital number...
Raw Counts to Engineering Units : Conversion Formula
We need to convert sensor raw counts to engineering units in a PLC system. Convert Raw Counts to Engineering Units We have a sensor which gives a raw value input...
Turbine Flow meter Coefficient and Scaling Factor
A digital turbine flowmeter generates 10 pulses per gallon of liquid passing through it. Determine the meter coefficient and calculate the scaling factor that are needed to develop an output...