ANSWERS TO FREQUENTLY ASKED QUESTIONS ABOUT ELECTRONIC PLANIMETERS
What is the difference between Roller & Polar Planimeters?
Roller planimeters are attached to wheels that allow unlimited horizontal travel and vertical travel within the limits of the arm movement. Polar planimeters are attached to a weighed base by and arm that allows movement with a circular area. Planix products contain identical electronics whether you choose roller or polar. Roller units offer more versatility.
What is the scale factor?
The scale factor is the x-scale multiplied by the y scale. (This must be computed when using the Planix 5 and the Planix 6 because they do not have a built-in scale computation.) The reading from the planimeter is then multiplied by this to obtain the area in the drawing.
What if the area I want to measure is larger than the reach of the planimeter arm?
All of the Planix instruments have a "hold and accumulate" feature. Subdivide the area to be measured into the smaller areas that are within the range of the unit. Measure each area pressing the hold key once to stop measurement and once again to initiate measurement once the planimeter is moved to the next area.
What direction should I move the tracer arm?
The tracer arm should be moved in a clockwise direction and returned to the original starting point. Moving the arm counterclockwise will give you a negative reading. This can be used to subtract smaller areas contained in larger ones. See instruction manual for details.
How accurate are the Planix planimeters?
Planix planimeters have a stated accuracy of 0.2% of the area measured. For accurate work, Planix recommends that the work be done slowly and carefully and the averaging function be used so that the final measurement will be the result of several measurements.
