Light Bars provide the primary means of guidance to the operator.
Light Bar Start-Up Checks
In order to make sure that the Light Bars are functioning and are configured correctly, Light Bar checks are performed when the AccuGrade System is first turned on.
The operator must observe the Light Bars during startup, in order to check that they are working correctly. The LEDs on the Light Bars flash in the following sequence on startup:
- LEDs on all Light Bars flash in sequence from the center outwards at the same time.
- The LEDs on the left Light Bar flash in sequence from bottom to top.
- The LEDs on the center (horizontal) Light Bar flash in sequence from left to right.
- The LEDs on the right Light Bar flash in sequence from top to bottom.
- The LEDs on all Light Bars flash at the same time, twice.
If any of the three Light Bars do not flash, check the cables and all of the connectors. Retest the Light Bars. If the Light Bars do not flash in the correct sequence, check the configuration in the Light Bar Connections dialog and retest.
Using the Light Bars
Up to three Light Bars can be installed. Each Light Bar shows different information for your blade position:
- Two vertically-mounted Light Bars give cut/fill guidance to the blade tip on each side.
- A horizontally-mounted Light Bar gives horizontal guidance, when an alignment has been selected.
Note: The guidance point that has focus is shown as "Blade: Left" on the first soft key of the guidance screens.
There are seven sets of LEDs on each Light Bar. Refer to Illustration 1.
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| Illustration 1 | g01120244 |
Tolerance LEDs
The LEDs light up from the center of the Light Bar to the outside of the Light Bar.
When the blade is on-grade or on-line, only the center LEDs of each Light Bar are illuminated. When any other LEDs are illuminated, the blade is off grade. When the blade moves away from the design, LEDs at one end of the Light Bar light up. The further to the outside that the LEDs are illuminated, the more off the design the blade is. In order to bring the blade back to the design, move the blade away from the LEDs.
Using Light Bars With Cross-Section View
The following screen, Illustration 2, shows how the Light Bars provide guidance and relate to the Cross-section View. In this example a road design is used on a dozer. The bottom corners of the blade symbol correspond exactly to the tips of your machine's cutting edge.
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| Illustration 2 | g01296651 |
The Cross-section View and the Light Bars show the following details:
- The blade is tilting down to the right.
- A black line shows the elevation of the design surface, which is also the working surface.
- A red line shows the temporary working surface that the Light Bars provide guidance to. The elevation of the temporary working surface is the design elevation "±" any vertical offset.
- The left blade tip is farther above the design surface than the right blade tip is.
- A vertical line shows the working horizontal alignment.
- "Blade: Left" and the red square on the blade symbol show that the horizontal Light Bar is providing online guidance to the left blade tip.
- The left blade tip is to the right of the working horizontal alignment.
Other Light Bar Behavior
The Light Bar LEDs provide some system status information as well as guidance:
- No design is loaded, the Light Bar leds are all turned off. In the text views, the guidance items appear as "N/A".
- There is power to the Light Bars but no signal from the gps display, the center and end groups of leds on each Light Bar are lit.
- When there are no high accuracy gps positions available, the leds at each end of each Light Bar flash.
- When the machine is outside the bounds of the design file, the leds at each end of each Light Bar flash.
Vertical Light Bar Tolerances
The LEDs show the distance away from the design. In the example shown in Illustration 3, the values in brackets are based on a tolerance of 0.050 meters. Actual tolerance values depend on the current Light Bar tolerance settings. For more information about setting the tolerance, Refer to Operation and Maintenance Manual, "Light Bar Scale - Set".
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| Illustration 3 | g01216699 |
Horizontal Light Bar Tolerances
The horizontal tolerances work in the same way as the vertical tolerances and you enter a separate tolerance value. The default horizontal tolerance is 0.100 meters.
Adjusting the Light Bar Brightness
The brightness of the Light Bar LEDs can be adjusted.
Refer to Operation and Maintenance Manual, "Brightness (Display & Light Bar) - Set".