background image

Servo pressure

Servo pressure is the pressure in the Servosystem needed to position and hold the pump on stroke. It
depends on system pressure and speed. At minimum servo pressure the pump will run at reduced stroke
depending on speed and pressure.
Minimum servo pressure at corner power holds the pump on full stroke at max speed and max
pressure.
Maximum servo pressure is the highest pressure typically given by the charge pressure setting.

Charge pressure

An internal charge relief valve regulates charge pressure. Charge pressure supplies the control with
pressure to operate the swashplate and to maintain a minimum pressure in the low side of the
transmission loop.

The charge pressure setting listed in the order code is the set pressure of the charge relief valve with the
pump in neutral, operating at 1800 min

-1

 [rpm], and with a fluid viscosity of 32 mm²/s [150 SUS].

Pumps configured with no charge pump (external charge supply) are set with a charge flow of 30 l/min
[7.93 US gal/min] and a fluid viscosity of 32 mm²/s [150 SUS].

The charge pressure setting is referenced to case pressure. Charge pressure is the differential pressure
above case pressure.
Minimum charge pressure is the lowest pressure allowed to maintain a safe working condition in the
low side of the loop. Minimum control pressure requirements are a function of speed, pressure, and
swashplate angle, and may be higher than the minimum charge pressure shown in the Operating
parameters tables.
Maximum charge pressure is the highest charge pressure allowed by the charge relief adjustment, and
which provides normal component life. Elevated charge pressure can be used as a secondary means to
reduce the swashplate response time.

Charge pump inlet pressure

At normal operating temperature charge inlet pressure must not fall below 

rated charge inlet pressure

(vacuum)

Minimum charge pump inlet pressure is only allowed at cold start conditions. In some

applications it is recommended to warm up the fluid (e.g. in the tank) before starting the engine and then
run the engine at limited speed. Maximum charge pump inlet pressure may be applied continuously.

Case pressure

Under normal operating conditions, the rated case pressure must not be exceeded. During cold start case
pressure must be kept below maximum intermittent case pressure. Size drain plumbing accordingly.

Auxiliary Pad Mounted Pumps. The auxiliary pad cavity of H1 pumps configured without integral charge
pumps is referenced to case pressure. Units with integral charge pumps have auxiliary mounting pad
cavities referenced to charge inlet (vacuum).

C

CAUTION

Possible component damage or leakage.
Operation with case pressure in excess of stated limits may damage seals, gaskets, and/or housings,

causing external leakage. Performance may also be affected since charge and system pressure are

additive to case pressure.

Basic Information

H1 Axial Piston Pumps, Single and Tandem

Operating parameters

 

©

 Danfoss | April 2017

11062168 | BC00000057en-US0602 | 23

Summary of Contents for H1 Series

Page 1: ...Basic Information H1 Axial Piston Pumps Single and Tandem powersolutions danfoss com...

Page 2: ...7 NFPE and AC controls added 0602 May 2016 Updated to Engineering Tomorrow design 0601 Nov 2010 Nov 2015 Various changes BA 0501 Jul 2009 First edition AA Basic Information H1 Axial Piston Pumps Singl...

Page 3: ...15 Manual Over Ride MOR 16 Swash plate angle sensor for NFPE and AC2 controls 17 Control Cut Off valve CCO valve 18 Displacement limiter 19 Life time 19 Speed and temperature sensor 20 Operating para...

Page 4: ...in the overall hydraulic system Danfoss hydrostatic products are designed with 14 different displacements cm in 045 053 060 068 069 078 089 100 115 130 147 165 210 250 45 0 2 75 53 8 3 28 60 4 3 69 68...

Page 5: ...ure bar psi 450 6525 400 5800 450 6525 400 5800 480 6960 480 6960 480 6960 480 6960 480 6960 480 6960 480 6960 480 6960 480 6960 480 6960 Weight dry W O PTO filter kg lb single 41 90 tandem 65 143 50...

Page 6: ...958 AX00000104en US H1 Axial Piston Tandem Pumps Size 045 053 Service Manual 520L0928 AX00000103en US H1 Axial Piston Single Pumps Size 069 165 Service Manual 520L0848 AX00000087en US Data sheets for...

Page 7: ...All H1 pumps are equipped with a combination high pressure relief and charge check valve The high pressure relief function is a dissipative with heat generation pressure control valve for the purpose...

Page 8: ...oad vehicle movement must be avoided The load or vehicle should be moved not more than 20 of maximum speed and for a duration not exceeding 3 minutes Damage to drive motor s is possible When the bypas...

Page 9: ...increase from 1 2 1 5 bar per 10 l min 17 4 21 8 psi per 2 64 US gal min For external charge flow the CPRV is set according to the table below Charge pressure relief valve flow setting for external ch...

Page 10: ...l which pressurizes one end of the servo piston while draining the other Pressure differential across the servo piston moves the swashplate A swashplate feedback link opposing control links and a line...

Page 11: ...es by means of a special lip seal MDC control P301 749 MDC schematic diagram P005 701 M14 M5 M4 M3 MDC operation In difference to other controls the MDC spool provides a mechanical deadband This is re...

Page 12: ...acement is proportional to the solenoid signal current but it also depends upon pump input speed and system pressure This characteristic also provides a power limiting function by reducing the pump sw...

Page 13: ...orward Input Digital Reverse Input Digital Sensor Sensor Drive Pedal Input Analog Nom Drive Pedal Input Analog Red Neutral Input Digital CC1 CC2p04 CC1p06 CC1p07 CC1p12 e g Hand Brake Seat Switch FNR...

Page 14: ...gnal activates one of two proportional solenoids that port charge pressure to either side of the pump servo cylinder The NFPE control has no mechanical feedback mechanism The pump displacement is prop...

Page 15: ...ent 0 Signal Current mA DCAvg Max Current H1 FDC control N a b a Forward Threshold b Reverse Threshold N Neutral Override Current P301 443 p 0 b a r p 0 b a r p 3 0 0 b a r Reverse Forward The pump di...

Page 16: ...ol spool which allows the pump to go on stroke The MOR should be engaged anticipating a full stroke response from the pump W Warning An o ring seal is used to seal the MOR plunger where initial actuat...

Page 17: ...ld direction The output signal give a linear output voltage for the various magnet positions in the sensing range The swashplate angle sensor is available for all NFPE and AC2 controls P301 750 25 20...

Page 18: ...signal Return to neutral time will be dependent on oil viscosity pump speed swashplate angle and system pressure When the solenoid is energized charge flow and pressure is allowed to reach the pump co...

Page 19: ...procedures are found in the H1 Service Manual Adjustments under operating conditions may cause leakage The adjustment screw can be completely removed from the threaded bore if backed out to far Displa...

Page 20: ...ller which interprets its rate of change as a speed The speed sensor uses two Hall sensors with specific distance and orientation resulting in a pulse train output shift of 90 between the two sensors...

Page 21: ...n oil T90 360 s For temperature range see the formula below The formula used to calculate the case oil temperature T 0 0102 1 795 VO T Temperature C VO Measured output voltage V Response time in oil T...

Page 22: ...The braking system must also be sufficient to hold the machine in place when full power is applied System pressure System pressure is the differential pressure between high pressure system ports It is...

Page 23: ...than the minimum charge pressure shown in the Operating parameters tables Maximum charge pressure is the highest charge pressure allowed by the charge relief adjustment and which provides normal comp...

Page 24: ...the durability of the transmission components but it may affect the ability of oil to flow and transmit power therefore temperatures should remain 16 C 30 F above the pour point of the hydraulic flui...

Page 25: ...with a ratio within the range of 35 45 75 10 2 or better has been found to be satisfactory For some open circuit systems and closed circuits with cylinders being supplied from the same reservoir a co...

Page 26: ...to entrance to the loop and the control system Pressure filtration provides a higher level of filtering efficiency than suction filtration Filters used in charge pressure filtration circuits must be r...

Page 27: ...sured resistance is 122 The bypass spool is designed so the bypass sensor switch will be closed before oil bypasses the filter element This gives the machine operator an indication that the filter is...

Page 28: ...n Quantity Order number Mating connector 1 Deutsch DTM06 2S Secondary wedge lock 1 Deutsch WM 2S Socket terminal 2 Deutsch 0462 201 20141 Danfoss mating connector kit 1 11031205 The H1 pumps with an i...

Page 29: ...f 150 mm 5 91 in Moving steel devices or parts are not allowed within a radius of 250 mm 9 84 in P003 356E mm in 38 1 50 150 min 5 91 250 min 9 84 37 1 46 Remote charge pressure filtration full flow R...

Page 30: ...ute This allows 30 seconds fluid dwell for removing entrained air at the maximum return flow This is usually adequate to allow for a closed reservoir no breather in most applications Locate the reserv...

Page 31: ...size selection Unusual application conditions may require a more detailed review of charge pump sizing Charge pressure must be maintained at a specified level under all operating conditions to prevent...

Page 32: ...on bearing life can be minimized by proper orientation of the load Optimum pump orientation is a consideration of the net loading on the shaft from the external load the pump rotating group and the ch...

Page 33: ...acceleration This factor depends on the application GS Calculation factor for max shock acceleration This factor depends on the application W Mass Weight of pump kg lb L Distance from mounting flange...

Page 34: ...a pump drive or plugged into an auxiliary pad of a pump Maintaining a spline engagement at least equal to the Pitch Diameter will also maximize spline life Spline engagements of less than Pitch Diame...

Page 35: ...splines Spline life can be maximized if an intermediate coupling is introduced between the bearing supported splined shafts Multiple pump installations must consider the loads from the entire pump sta...

Page 36: ...varies with overall line length and position Structure born noise is transmitted wherever the pump casing connects to the rest of the system The way system components respond to excitation depends on...

Page 37: ...0 000 t n p 600 Qe p Me kW Pe 198 000 t n p 1714 Qe p Me hp Variables Vg Displacement per rev pHP High pressure pNP Low pressure p pHP pNP n Input speed v Volumetric efficiency m Mechanical torque eff...

Page 38: ...Basic Information H1 Axial Piston Pumps Single and Tandem 38 Danfoss April 2017 11062168 BC00000057en US0602...

Page 39: ...Basic Information H1 Axial Piston Pumps Single and Tandem Danfoss April 2017 11062168 BC00000057en US0602 39...

Page 40: ...lutions ApS Nordborgvej 81 DK 6430 Nordborg Denmark Phone 45 7488 2222 Danfoss Power Solutions US Company 2800 East 13th Street Ames IA 50010 USA Phone 1 515 239 6000 Danfoss Power Solutions Trading S...

Reviews: