Thermo Scientific Thermolyne NCAT F85930, Инструкция по установке и эксплуатации

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Glossary
90 NCAT Asphalt Content Tester Thermo Scientific
Idle Mode:
This mode is entered on startup after initialization. Revision G software automatically transfers from
the program mode to the idle mode upon completion of the test. The furnace will idle at setpoint
temperature in preparation for the next test. The blower is “OFF” in the idle mode.
Initialization:
This procedure sets up and configures the tester for operator use when the Power Switch is depressed to
“ON”. Initialization time is approximately 5-15 seconds.
Lift Test:
This test measures the blower efficiency when the furnace is in an unloaded condition and is at room
temperature. The operator is required to tare the balance, depress the startstop key, and observe the
balance display. Normal lift measurements are minus 4-6 grams.
NCAT:
National Center for Asphalt Technology.
Offset Value:
This value is the temperature difference between the stabilized chamber displayed temperature value
and the chamber temperature verification value determined by the recalibration process.
Program Mode:
This mode is entered by depressing the start-stop key. The program mode is used to determine asphalt
content of a HMA sample, calibration of the HMA sample, or raw aggregate.
Temperature Compensation Factor:
This factor compensates for the loaded basket assembly weight reduction experienced when placed in
the ignition furnace chamber at temperature. The Temperature Compensation Factor is automatically
calculated by the furnace software. This factor must be employed in the ignition process to achieve
acceptable precision and accuracy specified by standard methods. This factor is subtracted from the
asphalt content.
Test Endpoint:
This is the point at which the HMA samples weight loss does not exceed the “Test Stability Threshold
Setting” for three consecutive one minute periods. Furnaces containing Rev. H software will end the
test, asterisk the endpoint reading on the printout, and switch from the program mode to the idle
mode at endpoint if the Auto Program Switching to Idle is employed.
Test Stability:
This adjustable variable defines the endpoint sensitivity by measuring the HMA sample mass loss and
comparing it to the test threshold setting. The test is complete when the measured mass loss does not
exceed the stability threshold setting for three consecutive one minute periods. The stabile indicator on
the front control panel indicates the test stability threshold (endpoint) has been attained.