Laser Technology UltraLyte LR B, Руководство пользователя

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Section #4 – Instrument Tests
37
Electronic Copy of LTI's UltraLyte LR B User's Manual - 2
nd
Edition © 2002
8. Check the alignment one last time. If the instrument does not
pass, repeat the Alignment Procedure (steps 1-7 on page 36).
9. Replace the plastic washers and cover screws when the
instrument passes the alignment test.
If you need assistance, contact Laser Technology, Inc. See
the inside front cover for LTI contact information.
Reference Frequency Test
Your UltraLyte LR B may not include the Reference
Frequency Test. It is a factory-defined option that is set
when the instrument is shipped.
The Reference Frequency Test allows you to check the accuracy of the
UltraLyte LR B’s internal timing circuitry. During the test, a frequency
counter is attached to the UltraLyte LR B’s serial port, and the Tx line of
the instrument’s serial port is toggled ON and OFF. The frequency
counter checks the accuracy of that interval.
The Reference Frequency Test should be done by a qualified
technician. Specific details about the test are located in the
UltraLyte Periodic Certification Manual. If you need
assistance, contact Laser Technology, Inc. See the inside
front cover for LTI contact information.
Instrument Confidence Checks
There are several ways to verify the measurement accuracy of a Lidar
instrument. You can verify it directly by measuring the speed of an
object traveling at a known speed, but this is seldom practical. The
nature of Lidar is such that it cannot be tricked by a vibrating object,
such as a tuning fork, into displaying a velocity. For these reasons, LTI
has designed the Fixed Distance Test and the Delta Distance Test.
LTI suggests that you do one of these tests each time the instrument
is taken on duty.
Your UltraLyte LR B may not include the Delta Distance
Test. It is a factory-defined option that is set when the
instrument is shipped.
Theses tests verify the accuracy of the two key elements of Lidar speed
measurement:
• Precise time measurements
• Ability to make mathematical calculations