Etesia HYDRO 124D, Техническое учебное пособие

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Knowing the pressure and the flow of the 4cc pump, we can determine the power available.
Max. power of the equipment circuit : 1.05 kW
The power take-off at the end of the camshaft (diesel engine) can transmit 7000 Watts (7kW) at most. We
have seen that we need 1.05 kW for the equipment circuit. That leaves 7-1.05 = 5.95 kW for the Power
take-off which gives us the maximum pressure that we have available : 156 bars
To keep a margin of safety, the pressure limiting device is set at 140 bars.
Maximum pressure of the Power take-off circuit : 140 bars
This pressure can be checked at the front of the machine on the large male hydraulic coupling on the
coupling plate.
Method : Connect a manometer that allows the reading of pressures up to 150 bars minimum onto one of
the large male hydraulic couplings. Activate the accessory ram control switch situated on the dashboard.
The diesel engine must be running at max. rate whilst the measurement is taken.
The power actually available is therefore :
Max. power of the PTO circuit : 5.3 kW
One way of checking the flow of the tandem pump is to measure the time it takes to raise and lower the
grassbox. The theoretical times are :
Raising time : 5.3 seconds
Lowering time : 5.2 seconds
The diesel engine must be running at max. speed whilst the measurement is taken.
Recapitulation :
Circuit Pump Min. flow (l/min) Max. flow (l/min) Pressure (bars)
Equipment circuit 4cc 2.4 5.7 110
Power take-off circuit 16cc 9.6 22.8 140