5.1 Measuring the angle
Once the array has been hoisted to its working height, ArraySight
uses intelligent interpolating algorithms to determine the resting
point of the array, while it is still moving after motor adjustment.
This is important because it means you can make accurate
measurements without waiting for the system to come to a
complete rest after adjustment. It typically takes around three
periods of oscillation, or pendulum swings of the array for the
sender unit to achieve an accurate measurement of the angle.
As a guideline, the angle display has the following accuracy:
Cycles
Accuracy
1 period of swing
±1.0
2 periods of swing
±0.5
3 periods of swing
±0.1
Clearly, the measurement cannot be relied upon when the motor
hoists are actually in operation. Once the hoist(s) have stopped,
the meter unit quickly resolves the measurement. A usable value for
the resting angle is normally displayed within a few seconds.
5.2 Measurement limits
ArraySight has a usable range of ±45° with full accuracy. The
sender unit sensor is capable of measuring angles up to ±90°, but
with reduced accuracy of ±1°. The additional range is available to
you to use, but it should be used with caution.
5.3 Adjusting angles using relative values
The angle of the flying frame can be re-adjusted to a new angle,
relative to its original angle. This is achieved by resetting the
sender unit to zero while in situ at the original angle as described
Chapter 4.1 "Resetting the angle (zeroing)" on page 13. The
array can then be tilted on the hoists, reading the value off the
adjustment on the meter unit, relative to the original position.
Note: When the sender unit has been reset in this way, its
true horizontal position will no longer display 0.00°. This is
why we recommend checking the horizontal position at the
start of each sender unit installation.
5 Using the system
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