Fluke 810 User Manual page 130

810
Users Manual
4. On belt or chain driven components, how
can I estimate output RPM when I am unable
to obtain a tachometer reading?
Obtaining the RPM value using the laser
tachometer is the preferred method for
determining running speed. However, the output
RPM value can be calculated using simple
arithmetic. For simple reduction two-pulley
(sheave) systems, use the following formula and
solve for the RPM of the driven pulley:
Diameter, driver pulley (sheave)
Diameter, driven pulley (sheave)
5. What happens if optional questions are not
answered during the machine setup?
To maximize the level of diagnostic confidence,
more information is always better than less.
Optional information, such as the number of
gear teeth or number of pump vanes, can often
be obtained through the component's user
manual or direct from the manufacturer.
Choosing to skip optional questions in the
machine setup could potentially result in an
overdiagnosis of the component's condition
("false positive").
A-2
RPM, driven pulley (sheave)
=
RPM, driver pulley (sheave)
6. Do gearboxes require any special setup in
the Tester?
To diagnose gearbox faults properly, you must
enter the shaft speeds, gear tooth counts or gear
ratios.
If selecting the shaft speed method for single
speed changers, it is critical to use the same
entry method (manual or tachometer) on both
input and output shafts.
For two or three-speed gearboxes, please refer
to the gearbox documentation or machine label
to determine gear ratios or gear tooth count.
7. What kinds of machinery can I diagnose with
the Tester?
The Tester can diagnose most common types of
rotating equipment, with the exception of
turbines, centrifuges (purifiers), diesel/gas
engines and generators. See the user's manual
for a complete list of equipment. However, some
equipment may be called by another name but
could otherwise be setup within the Test. For
example, a simple mixer within a food
processing plant may have a drive train
composed of a motor, coupling, gearbox and
propeller pump. When considering whether a
particular piece of equipment can be diagnosed
with the Tester, break the equipment down into
its most basic components and determine
whether those components can be tested.