Norac UC4 Total Control, Руководство оператора

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Sensing Further Ahead of the Boom
Moving the sensor farther ahead of the boom is not an acceptable solution
to any performance issues. The reason is that as the sensor is moved further
ahead, there will be an increasing height error at the nozzles. In other
words, the sensor and nozzle are at two different points in space thus
introducing an error for all but most level terrain. In severe terrain, this
height error can bring the nozzles close to the ground as the sensor reads
over the crest of a hill, or down into a ditch.
Sensor Capabilities
In order for the UC4 system to work at its maximum level of performance,
your sensors must be returning accurate height readings at the designed
frequency. Under typical conditions, Norac’s ultrasonic sensors can
provide accurate height readings from 9 inches to over 120 inches, and
return many height readings in one second. The SOIL target can be
identified through stubble, young crops, row crops, and normal trash. The
CROP target can be identified over cereal grains, specialty crops, and row
crops. See the next section for more information on CROP mode guidelines
There are two main steps to ensure sensor performance. The first step is
proper mounting. See Section 4.2 for more information on sensor
mounting. The second step is to ensure that the protective foam covers on
the sensors are kept clean, and that the ultrasonic transducer behind the
foam does not become corroded or excessively dirty. Extra foams are
shipped with your kit. The transducer is a maintenance item and can be
replaced at Norac Service locations. Transducers can last from three to ten
years, depending on conditions. Refer to Section 8.2 for more maintenance
information.
If the mouth of the sensor becomes wet, it is normal for the sensor to return
error messages until the transducer has dried off. This could include rain or
excessive overspray. Material can build up on the transducer if the sensor is
mounted too close to the spray nozzles. This is the reason the sensor must
be mounted at least 9 inches in front of the nozzles. It keeps the sensor
housing out of the normal region of overspray.
In the sprayer boom application, Norac’s ultrasonic sensors ignore any
target that is closer than 9 inches from the bottom of the sensor housing.
This region is called the blanking range. Operating the sensor at heights
near the blanking range is dangerous and will affect performance because
height readings can be very intermittent. This is the reason that each sensor
must be mounted at least 9 inches above the spray nozzles. The total height
to the target is then guaranteed to be 9 inches plus the minimum height
setting (15 or 22 inches by default). No control action can take place when
sensor heights are invalid or not available to the UC4 panel.