Bently Nevada 3300/50, Руководство по эксплуатации

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Tachometer Maintenance
132 I Specifications
INPUTS
Signal Inputs: R e d u n d a n t inputs. Any two of the following:
Proximity Probes. 0 to -24 or 0 to -18 Volt.
Magnetic Pickups. (Not allowed for Zero Speed Application)
3300 System (Rack) Keyphasors.
Input Impedance: 1 0 k Ohm
Input Frequency: 1 0 k H z Maximum
SIGNAL CONDITIONING
OK Detection:
83871-01
A Transducer is detected as NOT OK if the RPM reading changes more than 50% between
consecutive input triggers above 100 RPM. A Transducer must have three consecutive OK
readings before it can return to OK from a NOT OK status. A Transducer is also detected as
NOT OK if the RPM value is above 99,999 RPM or below 1 RPM.
Transducer Switching: T h e Tachometer automatically switches to the OK transducer if one should go NOT OK The
monitor uses the highest RPM reading of the two transducers, when both are OK
Input Threshold: J u m p e r optioned for Automatic or Manual. (Automatic not allowed on Zero Speed Tachometers)
Automatic Threshold: L i m i t e d to inputs above 5 Hz or 300 RPM at one event per revolution.
Hysteresis: J u m p e r selectable from 0.2 to 2.0 Volts.
Events per
Revolution:
255 Maximum, 0.1 Minimum
RPM ALERTS
Setpoints: A d j u s t a b l e from 1 to 99,999 RPM
Requirements: T h r e e valid input triggers above an over speed setpoint or below an under speed setpoint.
Alert Delay: O n e second or three valid input triggers, whichever is greatest.
RPM/MIN ALERT (Rotor Accel Tach Only)
Setpoint: A d j u s t a b l e from 20 to 9,980 RPM/MIN in 20 RPM/MIN steps.
Requirements: T h r e e valid input triggers above the RPM/MIN setpoint.
Alert Delay: O n e second or three valid input triggers, whichever is greatest.
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