Bently Nevada 3300/50, Operation Manual

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Tachometer Maintenance
12 Events Per Revolution Adjustment
83871-01 •
The Events Per Revolution Adjustment allows the Tachometer to observe a rotating shaft at other
than one Event per Revolution, This is the case when observing a multi-tooth gear or when observing
a shaft driven at some ratio of the actual rotor speed.
Events per Revolution Examples:
Example 1:
This example shows both probes observing a one
event per revolution Keyphasor. The Tachometer is
to indicate the speed of the shaft on the Keyphasor.
In this case, the events per revolution (E/R) is set to
1, The E/R numerator and denominator are both 1.
(1/1 = 1)
Example 2:
In this example both probes are observing a 24
tooth gear. The Tachometer i s t o indicate the
speed of the shaft on the 24 tooth gear, In this
case, the Events per Revolution (E/R) is set to 24.
The E/R numerator
is 24 and the denominator is
1. (24/1 = 24)
EVENTS PER REVOLUTION
NUMERATOR
EVENTS P E R R E V O L U T I O N
DENOMINATOR
TACHOMETER / S T O
INDICATE THE SPEED
OF T H I S SHAFT
EVENTS P E R R E V O L U T I O N
NUMERATOR
EVENTS PER REVOLUTION
DENOMINATOR
TACHOMETER I S T O
INDICATE THE SPEED
OF T H I S SHAFT
TACHOMETER I N S P E C I A L
EVENTS PER REVOLUTION
ADJUST MODE
fACH•AETER
24
m . e w e , * w o w s .
TACHOMETER I N S P E C I A L .
EVENTS PER REVOLUTION
ADJUST MODE
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