6.0 Diagnostic Parameters
The Eclipse Model 705 measurement engine runs through a
series of self-tests and will detect and report faulty operation.
The TRANSDUCER BLOCK displays these faults in the
DEVICE_STATUS parameter. Refer to Section 7.1.2 for
more information on specific faults and warnings.
BLOCK_ERROR is not used except for indicating Out of
Service (OOS).
When the Model 705 transmitter is initially powered on, the
measurement engine does not have enough valid measure-
ment cycles to make a decision about the output level. For
the first few seconds after power is applied, the
LEVEL_STATUS/QUALITY is “Uncertain,” the
SUB_STATUS is “Initial value,” and the LIMIT attribute is
“Constant.”
When the Model 705 is operating properly, the
LEVEL_STATUS/QUALITY is shown as “GOOD,” and
the SUB_STATUS is “Non-Specific.”
While changing the transmitter operational parameters using
the local display or through the system configuration tool (with
the MODE_BLK in OOS), the output might be inaccurate
because of the changing parameters. When the device is set to
OOS, the TRANSDUCER BLOCK will still output level but
the QUALITY will be shown as “Bad” and the SUB_STATUS
is “Out of Service.”
When the Enhanced Model 705 measurement cycle fails to
find a valid output level, the transmitter maintains the last
good value as the output and flags the failure. The LIMIT
attribute is the same as the last good measurement.
When the Enhanced Model 705 detects a level above the
highest measurement point of the probe the operational
mode is shown as “May Be Flooded.” This is due to the fact
that, since the actual level location above the top of some
probes is not known, the output may not be accurate.
The Model 705 operational mode is DRY_PROBE when
the level is below the end of the probe. Again, the output
may not be accurate, since the location of the level below the
end of the probe is not known. The TRANSDUCER
BLOCK output is calculated as LEVEL_OFFSET.
When in the dry probe condition, the Model 705 compares
the measured length of the probe to the value entered into
the PROBE_LENGTH parameter. If the measured value
does not match PROBE_LENGTH, a fault is reported. The
QUALITY will be shown as “Bad,” and the SUB_STATUS
is “Configuration error.”
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fieldbus
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