Bently Nevada 3300/50, Руководство по эксплуатации

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• Tachometer Operation
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83870-01
MONITOR FUNCTIONS (CONT)
ALERT - Pressing one o f the Alert switches on the front panel o f the monitor causes the
corresponding Alert setpoint to be displayed on the front panel. When the particular Alert setpoint
conditions have been met, the Alert LEDs will illuminate and the Alert relay contacts are activated.
FIRST OUT ALERT - A monitor with the First Out option selected flashes an Alert LED if that Alert was
the first in the rack. Pressing the RESET switch acknowledges the First Out.
ALERT RELAYS - Monitor Alerts can be programmed for either latching or nonlatching modes. In the
nonlatching mode, the alert resets automatically when the Alert no longer exists. In the latching
mode, the Alert condition must be reset manually by pressing the RESET switch on the front panel
of the System Monitor (or by closing the external reset contacts). The Alert will not reset if the Alert
condition still exists.
ALERT BYPASS - An Alert can be bypassed using a switch located behind the front panel. When
bypassed, an Alert condition no longer causes the Alert LEDs to illuminate or the relay to actuate.
Alert bypass can be during maintenance. Alert Bypass is indicated by the front panel BYPASS LED.
Other front panel functions are not affected by Alert Bypass. This function can be disabled using a
programmable jumper within the monitor.
MONITOR BYPASS - The monitor can be completely bypassed using the Monitor Bypass switch
located behind the front panel. When bypassed, the monitor is completely nonfunctional, and can
be removed from the system monitoring loop. After this function is activated, the normal system OK
operation (OK Relay) will be restored for the remaining active monitors in the rack.
PEAK HOLD - The PEAK HOLD function allows recall of the maximum RPM value obtained since the
last PEAK HOLD reset. The PEAK HOLD value is read by pressing both Alert buttons simultaneously.
The Tachometer retains the PEAK HOLD value even after loss of monitor power. PEAK HOLD is
cleared by shorting two adjacent testpoints located behind the front panel.
BUFFERED OUTPUTS - The BUFFERED TRANSDUCER A and B coaxial cable connectors on the
front panel of the monitor provide buffered signals both redundant transducers. These connectors
can be used to connect external equipment to the monitor.
RECORDER OUTPUT - Depending on the option selected, the recorder output levels proportional
to RPM (and RPM/MIN with the Rotor Accel. Tach.) are either 0 to -10Vdc, +1 to +5Vdc, or +4 to
+20mA.
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