KOHTECT BT-77
Current consumption 220��, 50 Hz AC, not more than 5��A.
Current consumption 220��, 50 Hz AC, not more than 5��A.
The limits of complementary error of the instrument at voltage changing from
The limits of complementary error of the instrument at voltage changing from
3.6��olts to 2.8��olts.
Probability of no-failure operation, not less than 0.92 per 2000 hrs.
The average instrument life, not less than 10 years.
Failure time, 1000 hours. The average failure time is set for stan-dard conditions
for operation.
Dimensions, not more than 60 х 110 х 30 (mm).
Weight, not more than 210 gram.
1.2 Overview on Rolling Bearing Condition Monitoring
Ideally, rolling bearing elements are separated by a protective lubricant film, which
impedes their collision. However, manufacturing defects, damages, which appear
during operation, dirt in the bearing, insufficient or incorrect lubrication – all these
factors cause the collision of the bearing elements and, as a result, acoustic
oscillations of a wide spectrum are generated in the bearing body.
A specially designed transducer (patent №18652) is used to filter out the part of this
spectrum that carries information on the bearing faults detection. The transducer filters
those acoustic oscillations which are generated by the bearing defects, and converts
them into electronic signal proportional to the magnitude of shock pulse signal, that is
amplified and measured by the BT-77 electronic unit in the relative units of decibels
(dB).
A real new bearing is just from the beginning of its use, a source of induced vibration,
the amplitude of the shock pulse of which is dB
i
.
The dB
i
, initial value depends on the large number of factors; however, in practice it is
possible to limit them to diameter D (mm) of the neck and its rotating speed � (rpm). The
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Summary of Contents for BT-77
Page 1: ...BT 77 Bearing Tester with Non Contact Tacho Operating Instruction Manual...
Page 2: ......
Page 4: ...KOHTECT BT 77...
