Bently Nevada 3300/50, Operation Manual

Page: 64 / 122

• Tachometer Maintenance
•
12
83871-01
Events Per Revolution Adjustment (Cont)
Example 3:
In this example, both probes are observing an
eleven tooth gear being driven from a 2 4
tooth gear. The Tachometer is to indicate the
speed of the shaft on the 24 tooth gear. In
this case, the Events per Revolution (E/R) is
set to 24. Although the probes are observing
the eleven tooth gear, they still detect 2 4
events per one turn of the indicated shaft.
The E/R numerator is set to 2 4 and the
denominator is set to 1. (24/1 = 24)
Example 4:
In t h i s example, b o t h probes a r e
observing a one event per revolution
Keyphasor on the same shaft with an
eleven tooth gear. The eleven tooth gear
is driven from a 2 4 tooth gear. The
Tachometer is to indicate the speed of the
shaft on the 24 tooth gear. In this case,
the Events per Revolution (E/R) is 24/11.
For each revolution of the indicated shaft,
the Keyphasor w i l l r o t a t e 2 4 / 1 1
revolutions. The E/R numerator is set to
24 and the denominator is set to 11.
I I TOOTH GEAR
I I TOOTH PEAR
GOTH PROBES OBSERVING
4EnDKASOR
'3 e
EVENTS P E R R E V O L U T I O N
NUMERATORO W
EVENTS P E R R E V O L U T I O N
DENOMINATOR
TACHOMETER I S TO
INDICATE THE SPEED
OF T H I S SHAFT
EVENTS P E R R E V O L U T I O N
NUMERATOR
TAcm:mETER
2 4
wARNiN3
w. moo mar
admomm
sez weft.
TACHOMETER I N S P E C I A L
EVENTS P E R R E V O L U T I O N
A D J U S T M O D E
EVENTS P E R R E V O L U T I O N
DENOMINATOR
Ka-11.1-05CA
TAcHOmETER I S TO
INDICATE r H E SPEED
OF T H I S SHAFT
24 TOOTH GEAR
T A O P : 6 1 e 1 E R
2 4
VARNING
= T .
sE1
A l o m m i M E 6
6 W W E I 4 6 • P L C W 1
TACHOMETER I N S P E C I A L
EVENTS P E R R E V O L U T I O N
ADJUST mOOE
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