Great Plains 1520P Operator Manual - Manual (Page 95)

5/6/2010 118-732M
93 Veris Drive Operating Instructions
7. Indicated speed fluctuating erratically:
a. Use speed simulator to troubleshoot speed loop. Leave tractor stationary and drive hydraulics do not
need to be engaged. If steady speed between 4-10 mph appears on cab console using speed simu-
lator, troubleshoot radar, wheel pickup sensor, hall effect module. If steady speed does not appear
with speed simulator, external controller may need replacement. Call Service Department.
b. Check radar gun angle.
c. Check gap between wheel sensor and pickup plate.
d. Check power to system < 12 volt power will cause drive to behave erratically - often problem mani-
fests itself in speed loop.
8. Drive shuts off while planting:
a. If it occurs after 20 seconds of not planting, such as turning on headlands, operation is normal safety
shutoff (on units with radar speed signal).
b. Check setting of speed signal interrupter switch - reposition as necessary to keep actuator from dis-
engaging while planting.
c. 1.5 second delay shutting off drive - causes: chain binding, inadequate hydraulics.
9. Drive will not achieve desired rate:
a. Recheck calibration number and rerun calibration procedure if necessary.
b. Check to make sure that your desired rate is within the range of the meter that is installed.
c. Inadequate hydraulic flow. Adjust flow control to higher position. Check with flow meter if flow is sus-
pect.
d. Field speed too high. Check maximum planting rate in seed chart for rate that you are planting.
e. Check sprocket combinations; see Assembly and Parts Manuals for the planter you are operating
(30P and 40P models).
f. Check speed shown on cab console against other speedometer - tractor, planter monitor. If drive
speed is significantly higher, recalibrate speed on drive.
10. Drive plants significantly higher than desired rate:
a. Recheck calibration number and rerun calibration procedure if necessary.
b. Ensure that you have installed the correct seed meter.
c. Check sprocket combinations; see Assembly and Parts Manuals for the planter you are operating
(30P and 40P models).
d. Check speed shown on cab console against other speedometer - tractor, planter monitor. If drive
speed is significantly higher, recalibrate speed on drive.
11. Drive continues to rotate after tractor has stopped:
a. Contamination or wear in Proportional Valve (PN#19798). Remove and inspect. Blow out with com-
pressed air. Check o-rings and reinstall. Replace if necessary.
12. Fluid weeping from motor shaft seal:
a. Excessive back pressure in return hose. Check quick coupler connection. Use motor control port for
return if available.