AgraTronix MT-PRO Manual De Instrucciones página 12

CaLIBRaTION CONSIdERaTION / LIMITS (CON'T)
1. Tester differences: Your moisture tester unit may not match a given
elevator tester. None of the testers exactly match the actual weighted
moisture of any given grain. There is no national standard for elevator
testers. The difference between moisture testers and various USDA
approved elevator testers is not a constant value. A correction at one
moisture level may not be valid for a different moisture level. Graph
1 illustrates how the moisture tester might compare to an elevator
tester over a broad range of moisture levels. The moisture tester
and most elevator testers (shown in graph by solid line) will closely
match those of the moisture tester (shown by dashed line) for that
range, as illustrated. However, as we get away from mid-range into
the high and low moisture levels, differences between elevator tester
and moisture tester not only become greater, but may switch from a
moisture tester reading higher than elevator tester to a reading lower
than the elevator tester. For example, in Graph 1, the area between
B and C represents the mid-range moisture. Moisture tester readings
match elevator tester readings in this area with an accuracy of plus
or minus 0.5 percent. The area between A and B represents the low
moisture range. Moisture tester readings differ more from elevator
tester readings, and are LOWER than elevator tester readings. The
area between C and D represents the high moisture range. Moisture
tester readings again differ more from elevator tester readings than
they did at mid-range moisture, but now the readings are HIGHER
than elevator tester readings.
2. Calibration Requirements: Graph 1 illustrates that moisture tester
readings closely match elevator tester readings for mid-range
moisture levels. (Graph is for illustration purposes only and does
not reflect actual test data.) Calibration changes required for grain
in this moisture range will be small, if any. However, if grain is very
dry (Low Moisture Range) or very wet (High Moisture Range), it
may be necessary to calibrate your moisture tester unit against the
elevator tester using a sample of your grain in both testers. Record
the calibration correction required. It will be valid for all testing in that
moisture range for that grain.
Operation
05-9