Tinius Olsen MP1200 - Arm Length Calculation; Height Offset

Tinius Olsen MP1200 Extrusion Plastometer Page 18-3
Operation Manual # 02002215
18.1.3 Arm Length Calculation
18.1.3.1 The physical length of the PPDT Arm, from its tip to the center of rotation of the encoder
shaft, should be about 152.4 mm (6.000 in.).
18.1.3.2
The relationship of the real and displayed Arm Lengths and Travels (change in position)
can be approximated as follows:
(Real Tvl / Real Arm Lgth) = (Displayed Tvl / Displayed Arm Lgth)
18.1.3.3 With some simple algebraic manipulation, the Real Arm Length can be estimated as:
Real Arm Lgth = (Real Tvl * Displayed Arm Lgth) / Displayed Tvl
18.1.3.4 When doing these calculations, use the total 25.4 mm (1.000 in.) travel. You may need to
repeat this several times.
NOTE: Always operate the calibrator downwards when taking readings.
18.1.4 Height Offset
18.1.4.1 Remove the Calibration device, and replace the orifice and piston. Place a weight on the
piston and position the PPDT arm beneath the weight.
18.1.4.2 Press the ZERO button to zero the PPDT.
Note: The sine operation translates the rotary motion of the encoder into a linear
value. The Offset is simply a value, relative to the true horizontal position of the
PPDT arm, that is added in after the sine correction to make the PPDT readings
agree with the true piston height.