Bently Nevada 3300/46, Operation Manual

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Ramp Differential Expansion Monitor Operation
84413-01
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MONITOR FUNCTIONS
RECORDER OUTPUT - Depending on the option selected, the recorder output levels proportional to
the measured differential expansion signal are 0 to -10Vdc, +1 to +5Vdc, or +4 to +20mA.
SELF TEST - The monitor has three categories of self test: Power-up, Cyclic, and User-invoked.
Power-up self test is performed automatically each time the monitor power is turned on. A series
of basic tests and transducer OK tests are performed.
Cyclic self test is performed automatically during monitor operation. Errors encountered during
cyclic tests disable the monitor, and flash error code on the LCD bargraph. If the error is
intermittent, the monitor will return to operation, but the error codes are stored for retrieval during
User-invoked self tests. Stored error codes are indicated by OK LEDs flashing at 5 Hz provided
that the channel is OK.
User-invoked test performs Power-up self test and allows error codes stored during cyclic tests
to be read and cleared. Stored errors are annunciated by flashing the OK LEDs at 5 Hz and
displaying the error codes on the front panel LCD bargraph.
Not OK Monitor Defeat - The Not OK Monitor Defeat function prevents faulty transducer wiring from
causing false alarms. If a transducer is determined to be Not OK, the channel OK LED goes off, the
Channel BYPASS LED comes on, the differential expansion signal is clamped to zero position,
alarming is disabled, and the OK relay deenergizes. If a channel's input signal returns to an OK
condition, the channel's OK LED will start flashing at 1Hz to indicate that the OK state is restored.
After ten seconds, the BYPASS LED will go off, and alarming is enabled. The RESET switch on the
System Monitor front panel must be pressed to stop the OK LED from flashing.
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