Installing The Grade Control Sensor
The grade control sensor can be mounted on either side of the machine, in any position required by the reference to be used. The reference can be a stringline or any firm surface, such as an adjacent mat, that follows the grade desired.
When a stringline is used, a right-angle grade follower is mounted on the grid arm. When a firm surface is used, a skate and/or ski assembly is mounted on the grid arm. The grid arm can be mounted on either sensor hub for either arrangement. (See illustrations on next page.)
The grid arm has guide holes that are used to position the grid arm on the sensor hub, either horizontally or at a 45 degree angle with the sensor. Regardless of the arrangement used, THE FLAT SURFACE IN THE CIRCUMFERENCE OF THE HUB SHOULD BE PARALLEL TO THE TOP OF THE SENSOR WHEN THE SENSOR IS NULLED.
RIGHT ANGLE GRADE FOLLOWER
RIGHT ANGLE GRADE FOLLOWER
SKATE ASSEMBLY TRAILING AT 45°
SKI ASSEMBLY TRAILING AT 45°
After the sensor has been mounted, set the sensor switch at "Standby", then connect the control cable to the connector on top of the sensor and to the connector on the rear bulkhead of the tractor. Use the connector on the same side of the machine as the sensor.
GRADE CONTROL ASSEMBLY
Installing The Slope Control Sensor
The primary requirement when installing the slope control sensor is that the sensor be nulled when the bottom of the screed is level from side to side. The machine is adjusted to meet this requirement before being shipped from the factory, but it is good practice to check the slope sensor adjustment before starting each job.
- 1. Position the machine on a level surface that has no cross slope, preferably a recently leveled grade. Lower the screed onto blocks and check the bottom of the screed with a surveyor's level or a 5-foot (1.52 m) carpenter's level. Adjust the blocks as necessary to level the screed.
- 2. Set the tow point lift selector switches at "Manual", then use the tow point lift switches to set both tow points at mid-travel.
- 3. Turn the thickness control cranks until they are both in the unloaded position (no load when the crank is turned either way).
- 4. Install the slope sensor on the slope beam and connect the cable at the sensor and at the rear bulkhead of the tractor.
- 5. Connect the remote setpoint cable to the slope sensor and set the setpoint at "0" slope.
- 6. Turn the slope beam control to set the beam at "0" slope.
- 7. With the ignition switch at "On", set the sensor switch at "Standby".
- 8. Loosen the jam nut and turn the gain adjusting screw clockwise to the stop. The needle in the meter should be centered. If the needle is centered, proceed to step 7. If the needle is not centered:
- a. Loosen the two screws at the joint of the amplifier and transducer covers. Back out the screw in the lower right corner of the transducer cover until the screw disengages. Remove the cover, exposing the slope sensor transducer.
- b. Loosen but do not remove the four transducer mounting cleats.
- c. Slowly turn the transducer until the needle centers in the meter, indicating null.
- d. Tighten the cleats and replace the cover. The slope sensor is now adjusted to the particular machine. If it is moved to a different machine, the same procedure must be repeated.
- 9. Loosen the jam nut, then turn the gain adjusting screw counterclockwise to the stop. Turn the adjusting screw clockwise 1/4 to 1/2 revolution. Tighten the jam nut.
The midpoint setting for the gain is just a starting point that may have to be adjusted after paving is started. Turning the adjusting screw clockwise will increase the gain and make the system more sensitive. Turning the screw counterclockwise will decrease the gain and make the system more sluggish.