Thermo Scientific Micro-Tech 9101, Reference Manual

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Initializing the Micro-Tech
Test Duration
Thermo Fisher Scientific Micro-Tech 9101/9201 Reference Manual, Rev J 2-11
You are now going to measure how long it takes for the belt in your
conveyor system to make
one revolution at maximum speed. You will
use this information to verify that the scale’s zero and span can be
properly set during the approximately six minutes it takes the Micro-
Tech to complete the zero-calibration procedure and span calibration
procedure.
The take-home message here is that, for the scale’s zero & span to be
accurate, the zero and span calibration procedures must fulfill the
following requirements.

The belt must make at least three complete revolutions.

The test must have a total running time of six (or more) minutes.
To help you work through the necessary calculations, here is a real-life
example.
We have just finished installing a 56ft-long conveyor at our facility that
has a belt length of 120 feet—that is, if the belt was removed from the
system, cut and laid out flat, it would extend to 120 feet. Next, we need
to know how long it takes for the belt to make precisely
one revolution
when running at maximum speed.
1. To do this, we drew a prominent chalk line across the belt directly
above the load cell, and timed (to the nearest second) how long it
took for the belt to make exactly
one revolution. We discovered it
took precisely 1 minute and 15 seconds. Thus,
—Time for completing one revolution = 75 seconds.
2. Six minutes contain 360 seconds (6 x 60 seconds). So the number of
revolutions the belt makes in 360 seconds is 4.80 (360/75).
—Number of belt revolutions made in 6 minutes = 4.80
—Revs rounded up to the nearest whole number = 5
Test Duration
Example