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Data storage and local parameter setting
Data storage (parameter 0x000C, Bit 1) is used for ease of
sensor replacement. When data storage is enabled the
configuration of a sensor is automatically sent to the new
sensor when sensors are replaced. In some cases the
switchpoints may need to be reconfigured.
The switchpoints set locally using the setter apply for
enabled data storage and for the new sensor when a
sensor is replaced.
Maintenance
The sensor requires only minimal maintenance. Keep the
optical window free of contamination (dust, fingerprints
etc.). If cleaning becomes necessary, the optical window
can be cleaned using a lint-free cloth and alcohol (ethanol,
isopropanol).
Lifetime Info
The parameter 0x0501
Lifetime
provides information about
the aging of the sensor.
Lifetime
Green
1
No restrictions in the sensor
function can be expected
Yellow
2
Restrictions in the sensor function
are possible, but not certain.
The sensor should be replaced at
the next maintenance cycle.
Red
3
Restrictions in the sensor function
can be expected. The sensor
should be replaced as soon as
possible.
The relative performance of the emitter LED is continually
measured and can be read out as part of predictive sensor
operation and early defect detection using the parameter
0x00BE
SensorLEDPower
. The value range is between
0 and 100.
Stresslevel Info
The parameter 0x0500
Stresslevel
provides information
about the electrical and thermal load on the sensor. This
enables the operator to check the ambient conditions and
change them so that negative effects on the sensor can be
prevented.
Lifetime
Green
1
Thermal and electrical condition
non-critical. A long service life can
be expected.
Yellow
2
Thermal or electrical condition not
optimal. No immediate overheating
risk.
Red
3
Thermal or electrical condition poor,
life expectancy seriously
compromised.
Excess Gain
The raw values provided for remitted light (excess gain)
enable early detection of contamination and misalignment
as well as generation of trends and maintenance
schedules. The excess gain can be read out using the
parameter 0x000BD
ExcessGain
. The value read is non-
linear and unitless. The higher the excess gain, the more
light reaches the sensor compared with the switching
threshold. The minimum read value 100 corresponds to a
minimum excess gain of 1, at which the sensor receives
just enough light to exceed the switching threshold.
The excess gain is recalculated each time the switching
threshold is undershot. The excess gain is calculated from
the ratio of the switching threshold and the maximum light
received when the switching threshold is exceeded.
In addition the excess gain is periodically updated with the
switching threshold is exceeded for a longer period of time.
Stability
The
Stability
process data bit indicates that the sensor is
operating at low excess gain. It is set when the sensor is in
the uncertain range (i.e. low excess gain) for at least five
successive switching cycles. One possible cause is
contamination and the sensor should then be cleaned. The
Stability
process data bit is reset when the sensor is
operating with sufficient excess gain for at least three
successive switching cycles.
