Variable Rate Fertilizer Overview

The variable rate fertilizer (VRF) system is monitored independently with the original GreenStar ™ display or through the Original GreenStar™ Mode on the GS2 display. To enter the Original GreenStar™ Mode, select Menu >> Original GreenStar Monitor button.

Warning messages do not appear on Original GreenStar Monitor screen. When an audible alert signals a warning, return to SeedStar™ 2 screens to view messages.

Variable Rate Fertilizer is comprised of two basic components.

1. An original GreenStar™ display or GS2 display in Original GreenStar™ Mode.
2. A SeedStar ™ Variable Rate Fertilizer controller mounted on the planter frame. This controller monitors pump rotational speed, piston stroke, ground speed, and distance traveled. Ground speed and distance are obtained from radar input.

The SeedStar™ Variable Rate Fertilizer system allows an operator to change the application rate from the cab while planting.

  • Fertilizer rates are adjustable for different soil types or for irrigated versus dry land soils.
  • Five different fertilizer rates are programmable into the system. While planting, the operator selects any one of the programed rates to change the application.
  • Two separate pumps are programmable for different rates.

A ground driven mechanism provides the power to rotate the pump. Once set, the programmed application rate is constant regardless of varying ground speeds.

Two pump output ranges are available. High and low ranges are determined by different sprocket combinations. Output rate is variable for either range.

A61356

Original GreenStar Monitor Button

GreenStar is a trademark of Deere & Company
SeedStar is a trademark of Deere & Company

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When a rate is selected, the controller monitors pump rotational speed, piston stroke, and distance traveled to calculate actual application rate. If calculated rate differs from selected rate, the controller adjusts the piston stroke to match selected rate. True ground speed is obtained with radar. Implement speed is obtained indirectly from pump rotational speed. The controller calculates percent slippage from the different speed readings and changes the pump stroke to compensate. If slippage exceeds a predetermined value, a warning is issued.

The following components must be active or engaged for proper system operation:

  • Contact Drive or Ground Wheel Drive
  • Radar
  • Pump RPM Sensor
  • Pump Stroke Position Sensor

Fertilizer systems are available in two configurations; flow divider and central manifold.

  • The flow divider is a device that controls product flow while maintaining constant pressure. This allows for maximum flexibility when changing application rates.
  • The central manifold system allows some adjustment, but is limited by overall system pressure. Product flow is controlled by orifices placed at each row. As rate is increased, pressure increases. Once pressure reaches a certain level, flow cannot be increased any further without damage to the system.

A variety of warnings and cautions are provided for customer assurance. Some examples are:

  • No power detected on motor drive
  • Over or under application!
  • Pump position sensor not detected
  • Pump 1 has no response to control
  • VRF system problem detected. Pump Number 2 calculated rates may not be accurate
  • VRF system sprocket change detected. Pump Number 1 recalibrated
  • Lost communications with mobile processor
  • Battery voltage out of range

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