Bently Nevada 3300/50, Operation Manual

Page: 89 / 122

Tachometer Maintenance
25 Test Alerts (Rotor Accel Tach.)
83871-01 i l l
0
ammo'
M I L
0
PROX M I TOR A
Cm—
0
0
PROx m TOR B
KEYPHASOR O R G E A R
7
J
1. Disconnect the COM and IN wiring from the Transducer
A and B terminals on the Signal Input Module.
2. Connect a function generator output to an oscilloscope
input. Adjust the function generator output until a sine or
square wave having sufficient amplitude to trigger the
tachometer is displayed.
3. Disconnect the function generator from the oscilloscope
input and connect it to the XDCR A and B terminals on the
Signal Input Module.
4. Adjust t h e function generator frequency until t h e
Tachometer displays an RPM reading below the over speed
setpoint or above the under speed setpoint.
5. Press the RESET switch and verify that the TRIGGER OK
LEDs are on, and the RPM Alert and RPM/MIN Alert LEDs
are off.
CAUTION
Tests w i l l exceed Alert
setpoint l e v e l s causing
Alerts to activate. This could
result in relay contact state
change. S e e B y p a s s
Section 19.
A.WARNING
High Voltage present
could c a u s e s h o c k ,
bums or death.
Do Not touch exposed
wires or terminals.
TACHOMETER
N a m s m u m m w
3600
Rpm
WA R N I N G
500
R P M / M I N
• I'"„„
A
S U F F E R E D 4 8 7 1 : M E R S
44
•
•