Great Plains 1520P Operator Manual - Manual (Page 94)

1510P and 1520P
118-732M 5/6/2010
92
3. Test Relay inside external controller
a. Use Relay Output Tester (PN 27860) to test relay inside external controller. Install tester to weather-pak
solenoid connector from external controller. With tractor engine off, start drive calibration function. Audi-
tory alarm should buzz for 1.5 seconds when drive is engaged in calibration mode. If alarm does not
sound, relay or external controller may need to be replaced. Call Service Department.
4. Check hydraulics:
a. Check to see if hydraulic lever is in detent position.
b. Hydraulic lever is in wrong detent direction - a check valve at outlet of motor prevents reverse rotation.
c. Make sure that both hoses are properly connected to tractor remotes.
d. Inadequate system pressure. Place pressure gauge at filter and check reading. If system pressure is be-
low tractor specifications, check system.
e. Power solenoid directly: DANGER: RAPID DRIVE ROTATION MAY OCCUR AND CAUSE SERIOUS IN-
JURY. KEEP CLEAR OF DRIVE AREA.
i. Disengage hydraulics.
ii. Reduce flow to 30-50%.
iii. Power solenoid directly by connecting power
weather-pak connector to solenoid weather-
pak connector. If drive doesn’t rotate, Propor-
tional Coil (PN 19799) may be defective.
Check continuity with meter, or energize with
12v power and check for magnetic pull with small screwdriver. Double-check connections on solenoid
cable. If solenoid energizes but drive does not rotate when powered directly, tractor hydraulics are not
properly engaged.
f. Excessive torque in drive system. Disconnect main drive chain to check for rotation under zero load.
Check for a problem with the mechanical portion of drive, such as foreign material wedged in meter, fro-
zen bearings, misaligned chains, or swelled grain in meter. Install pressure gauge at motor inlet. Pressure
should be 1000-1500 psi. If pressure is above 2000 psi, significant torque problems are present.
5. Check Speed signal (if drive rotates in calibration mode but not when planting):
a. No signal from speed sensor - check connection at sensor and at drive controller.
b. Excessive gap between wheel sensor and sensor plate - readjust to .030.
c. Use Speed Simulator (PN #27858) to troubleshoot speed loop. Leave tractor stationary and drive hydrau-
lics do not need to be engaged.
d. Test speed sensor and hall effect sensor; replace
sensor if simulated speed appears on cab con-
sole.
e. Test speed cable between speed sensor and hall
effect module; replace cable if simulated speed
appears on cab console.
f. Test hall effect module and cable to external con-
troller; replace module and cable if simulated
speed appears on cab console. If speed does not appear with speed simulator, external controller or chip
may need replacement. Call Service Department.
Drive rotates but not at desired speed:
6. Drive (out rate) fluctuating erratically:
a. If indicated field speed on drive is also fluctuating erratically, troubleshoot speed signal loop.
b. If field speed is steady, check for loose set screws on motor encoder, contamination of proportional valve,
or mechanical binding of chain on row unit.
Rapid drive rotation may occur and cause
serious injury. Keep clear of drive area.
Rapid drive rotation may occur and cause
serious injury. Keep clear of drive area.