DG – Two-point control, direct operated  
The variable pump can be set to a minimum swivel angle by  
connecting an external switching pressure to port X.  
This will supply control fluid directly to the stroking piston;  
a minimum control pressure of pst ≥ 50 bar is required.  
The variable pump can only be switched between Vg max  
▼ Circuit diagram  
1)  
MH  
X
or Vg min  
.
Please note that the required control pressure at port X is  
directly dependent on the actual working pressure pB in  
port B. (See control pressure characteristic curve).  
The maximum permissible switching pressure is 280 bar.  
L
B
Switching pressure pst in X = 0 bar Vg max  
Switching pressure pst in X ≥ 50 bar Vg min  
▼ Switching pressure characteristic curve  
120  
100  
L1  
S
50  
0
50  
100  
150  
200  
250 280  
▼ Circuit diagram, sizes 18 to 100  
working pressure pB [bar]  
L
B
DR – Pressure controller  
The pressure controller limits the maximum pressure at the  
pump outlet within the control range of the variable pump.  
The variable pump only supplies as much hydraulic fluid as  
is required by the consumers. If the working pressure  
exceeds the pressure command value at the pressure valve,  
the pump will regulate to a smaller displacement to reduce  
the control differential.  
▶ Initial position in depressurized state: Vg max  
▶ Setting range2) for infinitely variable  
20 to 280 bar pressure control.  
.
L1  
S
Standard is 280 bar.  
▼ Circuit diagram, size 140  
▼ Characteristic curve  
1) Only size 140  
2) In order to prevent damage to the pump and the system,  
the permissible setting range must not be exceeded.  
The range of possible settings at the valve is higher.  
Controller data  
NG  
280  
18  
28  
45  
71  
88  
100 140  
10 12  
Pressure  
increase  
4
4
6
8
9
Δp [bar]  
Δp [bar]  
[l/min]  
Hysteresis and  
repeatability  
maximum 3  
maximum approx. 3  
Pilot fluid  
consumption  
▼ Circuit diagram DRG nominal size 18 to 100  
20  
1
qv min  
qv max  
Flow qV  
X
Characteristic curve valid at n1 = 1500 rpm and θfluid = 50 °C.  
2
DRG – Pressure controller, remote controlled  
3
For the remote controlled pressure controller, the LS pres-  
sure limitation is performed using a separately arranged  
pressure relief valve. Therefore any pressure control value  
under the pressure set on the pressure controller can be  
regulated. Pressure controller DR see page 11.  
L
B
A pressure relief valve is externally piped up to port X for  
remote control. This relief valve is not included in the scope  
of delivery of the DRG control.  
When there is differential pressure of 20 bar Δp (standard  
setting), the quantity of control fluid at the port is X  
approx. 1.5 l/min. If a different setting (range 10 to 22 bar)  
is required, please state in plain text.  
As a separate pressure relief valve (1) we recommend:  
▶ a direct operated, hydraulic or electric proportional one,  
suitable for the control fluid mentioned above.  
L
1
S
1 The separate pressure relief valve and the line are not  
included in the scope of delivery.  
2 Remote controlled pressure cut-off (G).  
3 Pressure controller (DR)  
The max. length of piping should not exceed 2 m.  
▶ Basic position in depressurized state:Vg max  
.
▶ Setting range1) for pressure control 20 to 280 bar (3).  
Standard is 280 bar.  
▶ Setting range for differential pressure 10 - 22 bar(2)  
Standard is 20 bar.  
Unloading port X to the reservoir results in a zero stroke  
(standby) pressure which is approx. 1 to 2 bar higher than  
the defined differential pressure ∆p, however system influ-  
ences are not taken into account.  
▼ Circuit diagram, size 140  
1
X
▼ Characteristic curve DRG  
Controller data DRG  
NG  
18  
28  
45  
71  
88  
100 140  
Hysteresis and  
repeatability  
maximum 4  
Δp [bar]  
1) In order to prevent damage to the pump and the system,  
the permissible setting range must not be exceeded.  
The range of possible settings at the valve is higher.  
Pilot fluid  
[l/min]  
maximum approx. 4.5  
consumption  
Differential pressure ∆p:  
▶ Standard setting: 14 bar  
280  
If another setting is required, please state in plain text.  
▶ Setting range: 14 bar to 22 bar  
Relieving the load on port X to the reservoir results  
in a zero stroke (“standby”) pressure which lies  
about 1 to 2 bar  
higher than the defined differential pressure Δp,  
however, system influences are not taken into account.  
Controller data  
1)  
Stand by  
DR pressure controller data see page 11.  
Maximum flow deviation measured at drive speed  
n = 1500 rpm.  
qv min  
qv max  
Flow qV  
Characteristic curve valid for n1 = 1500 rpm and tfluid = 50 °C.  
NG  
18  
28  
45  
71  
88  
100 140  
4.0 6.0  
Flow  
0.9  
1.0  
1.8  
2.8  
3.4  
ΔqV max  
deviation  
[l/min]  
Hysteresis  
and repeat-  
ability  
maximum 4  
Δp [bar]  
Pilot fluid  
consumption  
[l/min]  
maximum approx. 3 to 4.5 (DFR)  
maximum approx. 3 (DFR1)  
Over the years, we have been committed to the production and research of Rexroth A10VSO Series 31 Axial piston variable pump .We  
not only provide high quality machinery and accessories for sale on the market, we also care about customers' profits and the impact of  
machinery on the environment.If you want to know more details, please contact us immediately!  
We mainly operating series as the following series：Rexroth A A10VSO 18 Pump  
Rexroth A A10VSO 28 Pump  
Rexroth A A10VSO 45 Pump  
Rexroth A A10VSO 71 Pump  
Rexroth A A10VSO 100 Pump  
1) Zero stroke pressure from pressure setting ∆p on controller (2)