Charge Pressure Range according to model code
Code
20
24
26
30
Actual charge
pressure, bar [psi]
20 ± 1.5
[290 ± 21.8]
24 ± 1.5
[348 ± 21.8]
26 ± 1.5
[377 ± 21.8]
30 ± 1.5
[435 ± 21.8]
The factory set pressures at 1800 min
-1
(rpm) pump speed and a reservoir temperature of 50°C
[120°F], and are referenced to case pressure. At higher pump speeds with higher charge flows the
charge pressure will rise over the rated setting. Depending on the pressure rating, the charge
pressure relief valve may have one or two springs.
3. Loosen the locknut and turn the adjusting screw clockwise to increase the setting, and
counterclockwise to decrease it.
The approximate adjustment per turn
Number of springs
Change per turn
1 Spring
consult factory
2 Springs
3.9 bar [56.6 psi]
4. Torque locknut to 12 N•m [9 lbf•ft], while holding the adjusting screw.
5. Remove the gauges and plug the ports, when the desired charge pressure setting is achieved.
Pressure Limiter Adjustment
W
Warning
Pumps with only HPRV valves no longer contain pressure limiter screens and retainers. To convert such
pumps to those with pressure limiter valves, please contact your Danfoss service partner.
H1P Base Models with pressure setting option B include PL screens and retainers.
Lock motor output shaft to adjust the pressure limiter setting. Lock the vehicle's brakes or rigidly fix the
work function so it cannot rotate.
Pressure limiter adjustment
System pressure gauge port MB
0 - 600 bar [0 - 10,000 psi]
1/4 in
43 N•m [32 lbf•ft]
Charge pressure gauge port M3
0 - 50 bar [0 - 1000 psi]
1/4 in
43 N•m [32 lbf•ft]
(on bottom)
System pressure gauge port MA
0 - 600 bar [0 - 10,000 psi]
1/4 in
43 N•m [32 lbf•ft]
Pressure limiter
adjusting screw
Pressure limiter
locking nut
HPRV valve
Endcaps are different for clockwise and counter clockwise rotation.
Service Manual
H1P 069—H1P 250 Axial Piston Single Pumps
Adjustments
©
Danfoss | September 2020
AX152886482551en-000504 | 35