Brandt SB4000, Operator'S Manual

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To insure the safe and reliable operation of the SB4000 Sprayer, it is necessary to use a tractor with appropriate
specifications. As a guideline, insure that these requirements are met:
1. Tractor Horsepower:
It is recommended that the tractor have a MINIMUM weight of 15,000 lbs (6800 kg). A fully ballast 120
horse power tractor can achieve this weight. Although the power is not required to pull the machine, it will
insure that the tractor/sprayer combination has sufficient power to maintain a constant forward speed under all
conditions and stability during operating and transporting conditions. Increase the power by 25% if operating
in soft field or hilly conditions.
2. Hydraulic System:
There are three different types of hydraulic systems used on tractors, the Open Centre system, the Closed
Centre (pressure compensated) System and the Closed Centre Load Sensing (flow and pressure compensated)
System. The is imperative that you know the type of system and it’s capabilities before choosing a sprayer
pump.
Open Center Systems
Note: Tractors with Open Center hydraulics should not be used on sprayers equipped with suspension.
In an Open Center System, the hydraulic pump puts out a constant flow. If the pump puts out more oil than the
motor can use, a portion of the oil must be bypassed around the motor. When the oil is bypassed around a
loop and does no work, the energy put into it by the pump turns into heat. Therefore, the amount of oil
bypassed should be kept to a minimum. Use the largest motor possible.
Before selecting a pump or installing any components from the Open Centre Tractor Hydraulics kit, attach a
flow and pressure meter to the tractor to determine the hydraulic system’s actual output. Make sure the oil is
warm and the engine is running at the speed it will be turning when the unit is in the field. If the hydraulic system
has a flow control in it, make sure it is turned to the wide open position.
Closed Center (Pressure Compensated) Systems
The Closed Center Pressure Compensated system has a variable displacement pump which will deliver flow at
the necessary rate to maintain a specified pressure. It is desirable to equip implements with a motor of a low
flow range that will cause the pump to operate between 1800 and 2100 psi [124 and 145 BAR]. A motor that
requires a large volume to obtain the correct implement speed usually causes the hydraulic pump in a closed
center system to operate at a lower pressure than desirable. This low pressure results in unnecessary flow and
the generation of heat that lowers the lubricating quality of the oil and can damage transmission parts. Use the
smallest motor possible.
Closed Center Load Sensing Systems (Flow and Pressure Compensating)
The Closed Center Flow Compensated System is a variation of the pressure compensated system, designed
primarily for more efficient operation and the generation of less heat. It works on the principle of maintaining
a constant pressure drop from the pump to the work port of the selector valve. Any variation in demand at the
motor will cause a change in flow. The system senses this change in flow due to the change in pressure drop
across the valve, and causes the pump to compensate by varying the pump flow. No restrictor is used in the
pressure line and no oil is bypassed.
3.3 EQUIPMENT MATCHING