Title: Graphs for Process Technology
Course: Open PRO130 Instrumentation I

Many of the gauge instruments used to measure fluid levels in process
technology equipment take a reading from a volume in a tank and produce
an output in milliamps (mA),volts (V), or pounds per square inch (PSI).

We can used linear equations to help us convert from percentages to
milliamps, or volts, or pounds per square inch.  This exercise will address
these conversions.

Note: If a tank is 100% full, then the digital signal on a gauge reads 20mA.
If the tank is 0% full, then the digital signal reads 4 mA.

Question:

a)  Use this information to describe two ordered pairs (x,y) where x        is the tank percentage and y is milliamps reading.

b)   Use the points described in part (a) to find the slope of the line between the two points.

c)  Write an equation in slope-intercept form relating the percentage to the millamps.

Watch this demonstration of how to solve the problem above:
Graphing Lines: Process Technology
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