Danfoss H1 User guide

Basic Information

H1 Axial Piston Pumps

Single and Tandem

www.danfoss.com

Basic Information

H1 Axial Piston Pumps, Single and Tandem

Revision history	Table of revisions
	Date	Changed	Rev
	December 2021	Added Hydraulic Displacement Control section	1001
	January 2021	Changed document number from 'BC00000057' to 'BC152886483968' and added	0901
		280cc information
	November 2019	Speed sensor, Integral Charge Pressure Filtration data changes.	0703
	April 2019	CCO topic update.	0702
	May 2018	Angle sensor for EDC controls added.	0701
	April 2017	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

2 | © Danfoss | December 2021

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Basic Information
H1 Axial Piston Pumps, Single and Tandem
Contents
Danfoss hydrostatic product family
A word about the organization of this manual.....................................................................................................................	5
General description of H1 family hydrostatic pumps..........................................................................................................	5
Overview of H1 Pumps Technical Specifications..................................................................................................................	6
H1 Pumps Literature Reference...................................................................................................................................................	7
Operation
Pressure Limiter Valves...................................................................................................................................................................	8
High Pressure Relief Valve (HPRV) and Charge Check Valve.............................................................................................	8
Bypass function.................................................................................................................................................................................	9
System Schematic for Single Pump...........................................................................................................................................	9
System Schematic for Tandem Pumps...................................................................................................................................	10
Charge Pressure Relief Valve (CPRV).......................................................................................................................................	10
Electrical Displacement Control (EDC)...................................................................................................................................	11
EDC Operation...........................................................................................................................................................................	11
Manual Displacement Control (MDC) ....................................................................................................................................	12
MDC operation..........................................................................................................................................................................	12
Neutral start switch (NSS)......................................................................................................................................................	13
Hydraulic Displacement Control (HDC).................................................................................................................................	14
HDC principle.............................................................................................................................................................................	14
Automotive Control (AC) ............................................................................................................................................................	15
Automotive Control connection diagram.......................................................................................................................	16
Forward-Neutral-Reverse (FNR) electric control.................................................................................................................	17
Non feedback proportional electric control (NFPE)..........................................................................................................	17
Fan Drive Control (FDC)...............................................................................................................................................................	18
Control Signal Requirements, FDC ....................................................................................................................................	18
Manual Override (MOR)...............................................................................................................................................................	20
Swashplate angle sensor for EDC controls...........................................................................................................................	21
Swash Plate Angle Sensor for NFPE and AC2 Controls.....................................................................................................	22
Control Cut Off Valve (CCO).......................................................................................................................................................	23
Brake gauge port with MDC.................................................................................................................................................	23
Displacement Limiter...................................................................................................................................................................	24
Life Time............................................................................................................................................................................................	24
Speed and Temperature Sensor...............................................................................................................................................	25
Description..................................................................................................................................................................................	25
Theory of Operation................................................................................................................................................................	25
Target Ring..................................................................................................................................................................................	25
Mating Connectors...................................................................................................................................................................	25
Speed sensor 4.5 – 8 V technical data...............................................................................................................................	26
Temperature sensor data.......................................................................................................................................................	26
Operating Parameters
Input Speed......................................................................................................................................................................................	28
System Pressure..............................................................................................................................................................................	28
Servo Pressure.................................................................................................................................................................................	29
Charge Pressure..............................................................................................................................................................................	29
Charge Pump Inlet Pressure.......................................................................................................................................................	29
Case Pressure...................................................................................................................................................................................	29
External Shaft Seal Pressure.......................................................................................................................................................	30
Temperature....................................................................................................................................................................................	30
Viscosity.............................................................................................................................................................................................	30
System design parameters
Fluid Specification.........................................................................................................................................................................	31
Fluid selection............................................................................................................................................................................	31
Filtration System.............................................................................................................................................................................	32
Suction Filtration............................................................................................................................................................................	33
Charge pressure filtration (full charge pump flow)...........................................................................................................	33
Remote Charge Pressure Filtration....................................................................................................................................	34
Integral Charge Pressure Filtration.....................................................................................................................................	35
H1P Filters Ordering Numbers.............................................................................................................................................	36
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Basic Information

H1 Axial Piston Pumps, Single and Tandem

Contents

Filter Bypass Characteristic....................................................................................................................................................	37
Bypass Sensor Clearance........................................................................................................................................................	37
Reservoir............................................................................................................................................................................................	38
Case drain.........................................................................................................................................................................................	38
Charge pump...................................................................................................................................................................................	39
Bearing loads and life ..................................................................................................................................................................	40
Mounting flange loads.................................................................................................................................................................	41
Shaft Torque for Splined Shafts................................................................................................................................................	42
Shaft Torque for Tapered Shafts...............................................................................................................................................	42
Shaft availability and torque ratings.......................................................................................................................................	43
Minimizing System Noise............................................................................................................................................................	44
Determination of Nominal Pump Sizes..................................................................................................................................	45

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Basic Information

H1 Axial Piston Pumps, Single and Tandem

Danfoss hydrostatic product family

A word about the organization of this manual

General information covering all displacements of the H1 range is given in the beginning of this manual. This includes definitions of operating parameters and system design considerations.

The next sections in the book detail the specific operating limitations for each frame and give a full breakdown of available displacements, features and options.

General description of H1 family hydrostatic pumps

The H1 family of closed circuit variable displacement axial piston pumps is designed for use with all existing Danfoss hydraulic motors for the control and transfer of hydraulic power. The H1 axial piston variable displacement pumps are of cradle swash-plate design and are intended for closed circuit applications.

Flow direction is reversed by tilting the swash-plate to the opposite side of the neutral (zero displacement) position. The flow rate is proportional to the pump input speed and displacement. The latter is infinitely adjustable between zero and maximum displacement.

H1 pumps can be used together in combination with other Danfoss pumps and motors in the overall hydraulic system.

•Danfoss hydrostatic products are designed with 15 different displacements (cm³ [in³]):

045	053	060	068	069	078	089	100	115	130	147	165	210	250	280
45.0	53.8	60.4	68.0	69.0	78.0	89.2	101.7	115.8	130.8	147.0	165.0	211.5	251.7	280.2
[2.75]	[3.28]	[3.69]	[4.15]	[4.22]	[4.76]	[5.44]	[6.21]	[7.07]	[7.98]	[8.97]	[10.07]	[12.91]	[15.36]	[17.10]

•Danfoss hydrostatic products are designed with many different pressure, load-life and control capabilities:

‒Electric Displacement Control (EDC)

‒Forward-Neutral-Reverse control (FNR)

‒Non-Feedback Proportional Electric control (NFPE)

‒Automotive Control (AC)

‒Fan Drive Control (FDC)

‒Manual Displacement Control (MDC)

‒Hydraulic Displacement Control (HDC)

‒Control-Cut-Off valve (CCO)

•High power density where all units utilize an integral electro-hydraulic servo piston assembly that controls the rate (speed) and direction of the hydraulic flow.

•Compatible with the Danfoss family of PLUS+1® micro-controllers for easy Plug-and-Perform installation.

•More compact and lightweight

•Improved reliability and performance

Go to the Danfoss website or applicable product catalog to choose the components that are right for your complete closed circuit hydraulic system.

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Basic Information

H1 Axial Piston Pumps, Single and Tandem

Danfoss hydrostatic product family

Overview of H1 Pumps Technical Specifications

The table shows the available range of H1 pumps as of this printing, with their respective speed, pressure, weight and mounting flange.

Feature	045	053	060	068	069	078	089	100	115	130	147	165	210	250	280
Displacement cm3	45.0	53.8	60.4	68.0	69.2	78.1	89.2	101.7	115.2	130.0	147.2	165.1	211.5	251.7	280.2
[in3]	[2.75]	[3.28]	[3.69]	[4.15]	[4.22]	[4.77]	[5.44]	[6.21]	[7.03]	[7.93]	[8.98]	[10.08]	[12.91]	[15.36]	[17]
Rated speed, min-1	3400	3400	3500	3500	3500	3500	3300	3300	3200	3200	3000	3000	2600	2600	2600
(rpm)
Max. speed, min-1	3500	3500	4000	4000	4000	4000	3800	3800	3400	3400	3100	3100	2800	2800	2800
(rpm)
Max. working	420	380	420	380	450	450	450	450	450	450	450	450	450	450	420
pressure, bar [psi]1)	[6092]	[5511]	[6092]	[5511]	[6527]	[6527]	[6527]	[6527]	[6527]	[6527]	[6527]	[6527]	[6527]	[6527]	[6092]
Max pressure, bar	450	400	450	400	480	480	480	480	480	480	480	480	480	480	450
[psi]	[6527]	[5802]	[6527]	[5802]	[6962]	[6962]	[6962]	[6962]	[6962]	[6962]	[6962]	[6962]	[6962]	[6962]	[6527]
Weight dry, kg [lb]	single: 41 [90]		single: 50 [110]		56	56	62	62	83	83	96	96	163	163	163
(without PTO/filter)	tandem: 65		tandem: 96.2		[123]	[123]	[137]	[137]	[187]	[187]	[211]	[211]	[360]	[360]	[360]
	[143]		[212]
Mounting flange	SAE B, 2-bolt				SAE C, 4-bolt				SAE D, 4-bolt				SAE E, 4-bolt

1) Applied pressures above maximum working pressure requires Danfoss application approval.

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Basic Information

H1 Axial Piston Pumps, Single and Tandem

Danfoss hydrostatic product family

H1 Pumps Literature Reference

Available literature for H1 Pumps

Title	Literature Type	Number
H1 Axial Piston Pumps, Single and Tandem	Product Line Overview	AM152886484212
H1 Axial Piston Pumps, Single and Tandem	Basic Information	BC152886483968
H1T 045/053/060/068 Axial Piston Tandem Pumps	Technical Information	BC152886483958
H1P 045/053 Axial Piston Single Pumps	Technical Information	BC152886483105
H1P 060/068 Axial Piston Single Pumps	Technical Information	BC152886483241
H1P 069/078 Axial Piston Single Pumps	Technical Information	BC152886483133
H1P 089/100 Axial Piston Single Pumps	Technical Information	BC152886482765
H1P 115/130 Axial Piston Single Pumps	Technical Information	BC152886483053
H1P 147/165 Axial Piston Single Pumps	Technical Information	BC152886482989
H1P 210/25/280 Axial Piston Single Pumps	Technical Information	BC152986484463
H1P 045/053/060/068 Axial Piston Single Pumps	Service Manual	AX152886481964
H1T 045/053/060/068 Axial Piston Tandem Pumps	Service Manual	AX152886481761
H1P 069–280 Axial Piston Single Pumps	Service Manual	AX152886482551

Data sheets for all pump sizes are available.

Further available literature

Title	Literature Type	Number
H1 Pump Electrical Displacement Control (EDC)	Electrical Installation	BC152886483648
H1 Pump 3-position Electric Control (FNR)	Electrical Installation	BC152886483708
H1 Pump Non-Feedback Prop. Electric Control (NFPE)	Electrical Installation	BC152886483538
H1 Pump Automotive Control (AC)	Technical Information	BC152986482596
H1 Automotive on PLUS+1 for MC024	Technical Information	BC152986484456
Speed and Temperature Sensor	Technical Information	BC152886482203
Pressure Sensor	Technical Information	BC152886484429
External Remote Charge Pressure Filter	Technical Information	BC152886484487
Design Guideline for Hydraulic Fluid Cleanliness	Technical Information	BC152886482150
Hydraulic Fluids and Lubricants	Technical Information	BC152886484524

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Basic Information

H1 Axial Piston Pumps, Single and Tandem

Operation

Pressure Limiter Valves

Pressure limiter valves provide system pressure protection by compensating the pump swash plate position when the set pressure of the valve is reached. A pressure limiter is a non-dissipative (non heat generating) pressure regulating system.

Each side of the transmission loop has a dedicated pressure limiter valve that is set independently. A pump configured with pressure limiter must have pressure limiters on both sides of the system pressure loop. The pump order code allows for different pressure settings to be used at each system port.

The pressure limiter setting is the maximum differential pressure between the high and low loops. When the pressure limiter setting is reached, the valve ports oil to the low-pressure side of the servo piston. The change in servo differential pressure rapidly reduces pump displacement. Fluid flow from the valve continues until the resulting drop in pump displacement causes system pressure to fall below the pressure limiter setting.

An active pressure limiter destrokes a pump to near neutral when the load is in a stalled condition. The pump swash-plate moves in either direction necessary to regulate the system pressure, including into stroke (overrunning) or over-center (winch payout).

The pressure limiter is optional on H1 pumps (except H1T 045/053 tandem pumps).

High Pressure Relief Valve (HPRV) and Charge Check Valve

All H1 pumps have a combination high pressure relief and charge check valve. The high pressure relief function is a dissipative (heat generating) pressure control valve for the purpose of limiting excessive system pressures. The charge check function replenishes the low pressure side of the working loop with charge oil.

Each side of the transmission loop has a dedicated HPRV valve that is non-adjustable with a factory set pressure. When system pressure exceeds the factory setting of the valve, oil is passed from the high pressure system loop, into the charge gallery, and into the low pressure system loop via the charge check.

The pump may have different pressure settings to be used at each system port. When an HPRV valve is used in conjunction with a pressure limiter, the HPRV valve is always factory set above the setting of the pressure limiter. The system pressure shown in the order code for pumps with only HPRV is the HPRV setting.

The system pressure shown in the order code for pumps with pressure limiter and HPRV is a reflection of the pressure limiter setting:

HPRVs are set at low flow condition. Any application or operating condition which leads to elevated HPRV flow will cause a pressure rise with flow above the valve setting. Consult factory for application review.

Excessive operation of the HPRV will generate heat in the closed loop and may cause damage to the internal components of the pump.

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Basic Information

H1 Axial Piston Pumps, Single and Tandem

Operation

Bypass function

The bypass function allows a machine or load to be moved without rotating the pump shaft or prime mover. The single pump HPRV valve also provides a loop bypass function when each of the two HPRV hex plugs are mechanically backed out three full turns.

Engaging the bypass function mechanically connects both A & B sides of the working loop to the common charge gallery.

Possible damage to hydromotor(s).

Excessive speeds and extended load/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. When the bypass function is no longer needed, care should be taken to re-seat the HPRV hex plugs to the normal operating position.

Bypass function not available for tandem pumps.

System Schematic for Single Pump

The schematic below shows the function of an H1P axial piston variable displacement pump with electric displacement control (EDC).

	M14	M6	1	2
				R1
		<![if ! IE]> <![endif]>R2
C1		C2
				M3 L2	MA
F00B	F00A					A
M4
		CW
M5						B
		S		L4	MB	P003 418E

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Basic Information

H1 Axial Piston Pumps, Single and Tandem

Operation

System Schematic for Tandem Pumps

The schematic below shows the function of H1T axial piston variable displacement tandem pumps with electric displacement control (EDC).

System schematic, tandem pumps

	M14			M14
C1	C2			C1	C2
	MB	X7	M3	MC
					L3
F00B	F00A			F00B	F00A
M5	CW				M4
					PTO
M4					M5
	MA A	B	E C D MD		P003 207E

Charge Pressure Relief Valve (CPRV)

The charge pressure relief valve is a direct acting poppet valve that opens and discharges fluid to the pump case when pressure exceeds a designated level. The charge pressure relief valve maintains charge pressure at a designated level above case pressure.

This level is nominally set with the pump running at 1800 min-1(rpm), and with a fluid viscosity of 32 mm²/s [150 SUS]. In forward or reverse, charge pressure will be slightly lower than in neutral position. The model code of the pump specifies the charge pressure relief valve setting. Typical charge pressure 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:

CPRV flow setting for external charge supply

Tandem 045/053	Single 045/053	Single 060—165	Single 210/250/280
30 l/min [7.9 US gal/min]	15 l/min [3.9 US gal/min]	22.7 l/min [6.0 US gal/min]	40.0 l/min [10.6 US gal/min]

Charge pressure relief valve

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Basic Information

H1 Axial Piston Pumps, Single and Tandem

Operation

Electrical Displacement Control (EDC)

An EDC is a displacement (flow) control. Pump swash plate position is proportional to the input command and therefore vehicle or load speed (excluding influence of efficiency), is dependent only on the prime mover speed or motor displacement.

The Electrical Displacement Control (EDC) consists of a pair of proportional solenoids on each side of a three-position, four-way porting spool. The proportional solenoid applies a force input to the spool, which ports hydraulic pressure to either side of a double acting servo piston. Differential pressure across the servo piston rotates the swash plate, changing the pump‘s displacement from full displacement in one direction to full displacement in the opposite direction.

A serviceable 170 μm screen is located in the supply line immediately before the control porting spool.

Under some circumstances, such as contamination, the control spool could stick and cause the pump to stay at some displacement.

Electrical Displacement Control

EDC schematic, feedback from swash plate

	M14
C1		C2
F00B	F00A	T	P
	Feedback from
	Swash plate	P003 478E

P003 191

EDC Operation

H1 EDC’s are current driven controls requiring a Pulse Width Modulated (PWM) signal. Pulse width modulation allows more precise control of current to the solenoids.

The PWM signal causes the solenoid pin to push against the porting spool, 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 linear spring provide swashplate position force feedback to the solenoid. The control system reaches equilibrium when the position of the swashplate spring feedback force exactly balances the input command solenoid force from the operator. As hydraulic pressures in the operating loop change with load, the control assembly and servo/swashplate system work constantly to maintain the commanded position of the swashplate.

The EDC incorporates a positive neutral deadband as a result of the control spool porting, preloads from the servo piston assembly, and the linear control spring. Once the neutral threshold current is reached, the swashplate is positioned directly proportional to the control current. To minimize the effect of the control neutral deadband, we recommend the transmission controller or operator input device incorporate a jump up current to offset a portion of the neutral deadband.

The neutral position of the control spool does provide a positive preload pressure to each end of the servo piston assembly.

When the control input signal is either lost or removed, or if there is a loss of charge pressure, the springloaded servo piston will automatically return the pump to the neutral position.

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Basic Information

H1 Axial Piston Pumps, Single and Tandem

Operation

Manual Displacement Control (MDC)

A Manual proportional Displacement Control (MDC) consists of a handle on top of a rotary input shaft. The shaft provides an eccentric connection to a feedback link. This link is connected on its one end with a porting spool. On its other end the link is connected the pumps swashplate.

This design provides a travel feedback without spring. When turning the shaft the spool moves thus providing hydraulic pressure to either side of a double acting servo piston of the pump.

Differential pressure across the servo piston rotates the swash plate, changing the pump’s displacement. Simultaneously the swashplate movement is fed back to the control spool providing proportionality between shaft rotation on the control and swash-plate rotation. The MDC changes the pump displacement between no flow and full flow into opposite directions.

Under some circumstances, such as contamination, the control spool could stick and cause the pump to stay at some displacement.

For the MDC with CCO option the brake port (X7) provides charge pressure when the coil is energized to activate static function such as a brake release. The X7 port must not be used for any continuous oil consumption.

The MDC is sealed by means of a static O-ring between the actuation system and the control block. Its shaft is sealed by means of a special O-ring which is applied for low friction. The special O-ring is protected from dust, water and aggressive liquids or gases by means of a special lip seal.

Manual Displacement Control	Pump displacement vs. control lever rotation
			100 %
			<![if ! IE]> <![endif]>Displacement
	"A"	-d -b	-a	"0"	Lever rotation	d	"B"
		-c			a	b c
			100 %			P301 752
		Deadband on B side: a = 3° ±1°
		Maximum pump stroke: b = 30° +2/-1°
		Required customer end stop: c = 36° ±3°
		Internal end stop: d = 40°

MDC operation

The MDC provides a mechanical dead-band required to overcome the tolerances in the mechanical actuation. The MDC contains an internal end stop to prevent turning the handle into any inappropriate position.

The MDC provides a permanent restoring moment appropriate for turning the MDC input shaft back to neutral position only. This is required to take the backlash out of the mechanical connections between the Bowden cable and the control.

High case pressure may cause excessive wear and the NSS to indicate that the control is not in neutral position. In addition, if the case pressure exceeds 5 bar there is a risk of an insufficient restoring moment. The MDC is designed for a maximum case pressure of 5 bar and a rated case pressure of 3 bar.

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Basic Information

H1 Axial Piston Pumps, Single and Tandem

Operation

•Customers must install some support to limit the setting range of their Bowden cable to avoid an overload of the MDC.

•Customers can apply their own handle design but they must care about a robust clamping connection between their handle and the control shaft and avoid overload of the shaft.

•Customers can connect two MDC’s on a tandem unit in such a way that the actuation force will be transferred from the pilot control to the second control. The kinematic of the linkages must ensure that either control shaft is protected from torque overload.

C Caution

Using the internal spring force on the input shaft is not an appropriate way to return the customer connection linkage to neutral, or to force a Bowden cable or a joystick back to neutral position. It is not applicable for any limitation of the Bowden cable stroke, except the applied torque to the shaft will never exceed 20 N•m.

Neutral start switch (NSS)

The Neutral Start Switch (NSS) contains an electrical switch that provides a signal of whether the control is in neutral. The signal in neutral is Normally Closed (NC).

Neutral start switch schematic

	M14
M5	M4	M3
		P005 702

Neutral start switch data

Max. continuous current with switching	8.4 A
Max. continuous current without switching	20 A
Max. voltage	36 VDC
Electrical protection class	IP67 / IP69K with mating connector

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Basic Information

H1 Axial Piston Pumps, Single and Tandem

Operation

Hydraulic Displacement Control (HDC)

HDC principle

An HDC is a Hydraulic Displacement Control. Pump swashplate position is proportional to the input command and therefore vehicle speed or load speed (excluding influence of efficiency), is dependent only on the prime mover speed or motor displacement.

The HDC control uses a hydraulic input signal to operate a porting spool, which ports hydraulic pressure to either side of a double acting servo piston. The hydraulic signal applies a force input to the spool which ports hydraulic pressure to either side of a double acting servo piston. Differential pressure across the servo piston rotates the swashplate, changing the pump’s displacement from full displacement in one direction to full displacement in the opposite direction. Under some circumstances, such as contamination, the porting spool could stick and cause the pump to stay at some displacement.

A serviceable 175 μm screen is located in the supply line immediately before the control porting spool.

HDC control

P400520

HDC schematic

X1		M14	X2

F00B	Feedback from	F00A	T	P
	Swashplate
				P400519

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