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Hydrostatic Fan Drives
Hydrostatic Fan drive with Variable or Fixed Pump
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Advantages of fixed pumps
- Minimum system price
- Compact dimensions
Advantages of variable pumps
- Optimum adaptation of the pump output to the required fan power
- High system efficiency
- Low fuel consumption
A 10 variable pumps with electro-hydraulics pressure control (ED)
The electro-hydraulic pressure control ED has been developed especially for controlled fan drives with A10 variable pumps from series 31 and 52. This enables low-cost, compact and flexible layout of the complete system.
This pressure control regulates maximum system pressure by means of a variable current to the pump solenoid inverse proportional to the current.
In fan drive systems, the control electronics convert the various inputs from the temperature sensor into a solenoid current.
When changing drive speed (engine speed) the control maintains an unchanged pressure level and the pump swivel angle changes keeping the flow equivalent to the actual required fan motor flow, making the fan speed without any hydraulic losses independent of engine speed.
A failure in the control system (i.e. broken cable somewhere) causes the system to go to maximum pressure and maximum fan speed (fail safe).
Advantages
- Optimum system efficiency
- Compact design
- Proven A10-technology
- Fast response times and high degree of accuracy
- Easy to drive, standard solenoids (12V resp. 24V)
- Valve variations with high insulations class available (IP69K, salt water proof and explosion proof)
- Same valve for all pumps sizes
Relevant links for Fan Drives
Back to Fan Drives Home Page
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