14
020203.06
Electro-Hydraulic Pumps
Hydraulic steering system, cylinder with (a) steering
pump(s) and EHP
Fill the system via the filling connection in the steering pump; the
EHP tank will have to be filled with oil via the compensating line.
A steering gear with two steering pumps should be filled up at the
uppermost steering pump.
In the next step, fill and bleed the EHP and the cylinder as described
above.
Then fill and bleed the steering pumps according to the manufactu-
rer’s instructions.
General
Make sure to repeatedly check the oil level for the first few days after
filling; if necessary, refill the oil.
The oil level may initially decrease since finely distributed air escapes
from the oil.
6
Maintenance
- The oil level should be checked regularly.
If the installation consists only of an EHP and a cylinder, the oil
level in the EHP tank must be checked.
If the installation also includes one or more steering pumps, the
oil level in the (upper) steering pump must be checked.
- Change the hydraulic oil once every two years or every 200 oper-
ating hours.
7
Technical specifications
Type EHP
:
EHPA R2
EHPB R2
EHPC R2
Electromotor
Type
:
Reversible, permanent magnet, DC motor
Voltage
:
12 V
24 V
12 V
24 V
12 V
24 V
Current at no load
:
6.5 A
4.0 A
7.5 A
4.8 A
9.0 A
6.0 A
Current at max.
:
9.5 A
6.0 A
12.5 A
6.9 A
15 A
8.9 A
Hydraulic pump
Type
:
Plunger pump
Capacity
:
350 cm
3
/min (21.3 cu.inch/min)
700 cm
3
/min (42.7 cu.inch/min)
950 cm
3
/min (57.9 cu.inch/min)
Relief valve
Setting
:
50 bar (50 kgf/cm
2
, 4905 kPa) (711 psi)
Buffer tank
Capacity
:
0.16 liters (0.035 Imp. gallon)
Connections
Pump
:
couplings for tubing 8 mm O.D./ 10 mm O.D. are separately available
Buffer tank
:
7/16 - 20 UNF female
Fuse
In the primary circuit
:
20 A
1)
15 A
1)
25 A
1)
15 A
1)
30 A
1)
20 A
1)
Weight
Excluding the oil
:
2.3 kg (5 lbs)
1)
Based on 'Fast Acting (F) fuse in accordance with the SAE J 1284 norm
Hydraulic medium
Hydraulic oil
: in accordance with ISO VG 15
Viscosity
: 22 cSt at 40˚C
Viscosity index
: above 100
Solidification point
: lower than -30˚C
Double check valve
:
G 1/4
Type of check valve
: Double-controlled check valves
Relation piston-check-valve
: 4 : 1
Connections
: G 1/4 female thread
Weight, excluding the connections : 2.2 kg (5 lbs)
The following hydraulic oils match the listed specifications:
VETUS
: Hydraulic oil ISO VG 15
Shell
: Tellus 22
Esso
: Nuto H22
Texaco
: Rando oil HD22
BP
: HLP22
