Product Overview

The A20VLO190LE2E/10L-NZD24N00-S and A20VLO190EP6D/10L-NZD24N00H-S are Bosch Rexroth A20VLO Series 10 variable displacement axial piston double pumps.

The current Bosch Rexroth RE 93100 technical document defines the A20VO/A20VNO/A20VLO platform as a compact back-to-back double pump with two axial piston rotary groups in swashplate design for open-circuit hydrostatic drives. The platform is intended for mobile and industrial applications and is designed for multi-circuit hydraulic systems. For nominal sizes 190 and 260, A20VLO is the version equipped with a charge pump.

For size 190, Rexroth specifies:

• 192.7 cm³/rev per rotary group
• 350 bar nominal pressure
• 400 bar maximum pressure
• 2500 rpm nominal speed at Vgmax
• 2 × 482 L/min theoretical flow at nnom and Vgmax
• 562 kW theoretical power at Δp = 350 bar
• 2147 N·m theoretical torque at Vgmax and Δp = 350 bar
• approximately 7.6 L case volume
• approximately 213 kg weight without through drive.

The two supplied complete configurations use different control technologies:

• A20VLO190LE2E/10L-NZD24N00-S: legacy LE2-family electrically proportional power override.
• A20VLO190EP6D/10L-NZD24N00H-S: EP6 proportional electric control with pressure cut-off.

For replacement applications, complete model-code verification is essential. Our replacement approach focuses on in-place interchangeability supported by 100% simulated working-condition testing.

Technical Specifications

A20VLO190LE2E/10L-NZD24N00-S

• Brand: Bosch Rexroth
• Series: A20VLO Series 10
• Complete Model Code: A20VLO190LE2E/10L-NZD24N00-S
• Product Type: Axial Piston Variable Double Pump
• Circuit: Open Circuit
• Architecture: Two back-to-back swashplate axial piston rotary groups
• Displacement: 192.7 cm³/rev per rotary group
• Calculated Total Geometric Displacement: 385.4 cm³/rev for both groups
• Rated Speed at Vgmax: 2500 rpm
• Maximum Published Speed for Size 190: 2500 rpm under the published conditions
• Nominal Pressure: 350 bar
• Maximum Pressure: 400 bar
• Maximum-Pressure Single Operating Period: <1 s
• Maximum-Pressure Total Operating Period: 300 h
• Theoretical Flow: 2 × 482 L/min
• Calculated Combined Theoretical Flow: 964 L/min
• Theoretical Power: 562 kW at 350 bar
• Theoretical Torque: 2147 N·m at 350 bar
• Case Volume: approximately 7.6 L
• Reference Weight: approximately 213 kg without through drive.

Control

• Control Code: LE2E
• Control Family: LE2 electrically proportional power override
• Control Logic: Electrical current reduces the mechanically established power setting.
• Voltage: 24 V DC for the LE2 family
• Beginning of Control: 200 mA
• End of Control: 600 mA
• Current Limit: 0.77 A
• Nominal Resistance at 20°C: 22.7 Ω
• Dither Frequency: 100 Hz
• Duty Cycle: 100%.

Model-Code Configuration

• L: Integrated charge-pump version for size 190
• O: Double pump, open circuit
• 190: Nominal size 190
• 10: Series 10
• L: Counterclockwise rotation viewed from the drive shaft
• N: NBR sealing system with FKM shaft-seal ring
• Z: DIN 5480 splined shaft
• D: SAE J744 four-bolt mounting flange
• 24: SAE pressure/suction flange arrangement with metric fastening threads
• N00: Without through drive
• -S: Historical special-version suffix not independently decoded in the current general type-code table.

The exact LE2E legacy suffix should be confirmed from the original nameplate or factory configuration record. The published electrical values above are the documented LE2 family values.

A20VLO190EP6D/10L-NZD24N00H-S

• Brand: Bosch Rexroth
• Series: A20VLO Series 10
• Complete Model Code: A20VLO190EP6D/10L-NZD24N00H-S
• Product Type: Axial Piston Variable Double Pump
• Circuit: Open Circuit
• Displacement: 192.7 cm³/rev per rotary group
• Calculated Total Geometric Displacement: 385.4 cm³/rev
• Rated Speed: 2500 rpm
• Nominal Pressure: 350 bar
• Maximum Pressure: 400 bar
• Maximum-Pressure Single Operating Period: <1 s
• Maximum-Pressure Total Operating Period: 300 h
• Theoretical Flow: 2 × 482 L/min
• Theoretical Combined Flow: 964 L/min
• Theoretical Power: 562 kW
• Theoretical Torque: 2147 N·m
• Case Volume: approximately 7.6 L
• Reference Weight: approximately 213 kg without through drive.

Control

• Control Code: EP6D
• Control Type: Proportional Electric Control with Pressure Cut-Off
• EP6: 24 V proportional solenoid control with manual override and spring return
• Beginning of Control: 200 mA
• End of Control: 600 mA
• Current Limit: 0.77 A
• Nominal Resistance at 20°C: 22.7 Ω
• Dither Frequency: 100 Hz
• Duty Cycle: 100%
• Pressure Cut-Off Adjustment Range: 50–350 bar.

Pressure Cut-Off Function

The EP6D pressure cut-off reduces pump displacement toward Vgmin after the configured pressure command value is reached. Rexroth states that the pressure cut-off overrides the current-dependent electrical displacement control below the pressure command limit.

Model-Code Configuration

Shared verified configuration elements include:

• A20VLO190: size-190 charge-pump double-pump platform
• 10: Series 10
• L: counterclockwise rotation viewed from the drive shaft
• N: NBR seal arrangement with FKM shaft seal
• Z: DIN 5480 splined shaft
• D: SAE J744 four-bolt mounting flange
• 24: SAE pressure/suction flange arrangement with metric fastening threads.

The complete historical N00H-S suffix should be confirmed against the original nameplate/order record rather than assigned an unsupported meaning.

Engineering Difference Between the Two Configurations

A20VLO190LE2E

The LE2 control family combines a mechanically established power setting with an electrically proportional override.

The hydraulic controller maintains the defined power characteristic, while the electrical signal can reduce the power setting. Rexroth describes the power controller as regulating displacement according to working pressure so that the specified drive power is not exceeded at constant drive speed.

For this configuration, replacement testing should therefore focus on:

• Drive speed
• Basic power setting
• Maximum flow
• Electrical override current
• Current-to-power response
• Pressure response
• Destroke stability

A20VLO190EP6D

The EP6D configuration uses proportional electrical displacement control with an integrated pressure cut-off.

The electrical command controls displacement during normal operation, while the pressure cut-off takes priority after the configured pressure threshold is reached.

For this configuration, replacement testing should focus on:

• Solenoid current
• Displacement response
• Pressure cut-off setpoint
• Destroke speed
• Recovery response
• Pressure-flow stability

Key Technical Advantages

1. Compact back-to-back double-pump architecture

The A20VLO integrates two axial piston rotating groups into a compact back-to-back package. Rexroth explicitly describes the platform as a solution for multi-circuit systems, reducing packaging requirements compared with separately mounted pump assemblies.

2. Integrated charge pump on size 190

For A20VLO size 190, the type code identifies the version with an integrated charge pump. This configuration is different from the equivalent A20VO arrangement without the L charge-pump designation.

3. High-pressure 350/400 bar class

The size-190 Series 10 platform is specified at 350 bar nominal and 400 bar maximum pressure. The maximum-pressure figure has an explicit time definition and should not be represented as a continuous operating rating.

4. High displacement and flow capacity

At 192.7 cm³/rev per rotary group and 2500 rpm, Rexroth specifies 2 × 482 L/min theoretical flow. These are theoretical values before efficiency and tolerance effects and are therefore appropriate as design-reference data rather than guaranteed field flow.

5. LE2 electrically proportional power limiting

The LE2 architecture provides electronic reduction of the mechanically established power setting. This allows the hydraulic system’s power demand to be adapted to an electronic load-limiting strategy.

6. EP6D electronic displacement control with pressure cut-off

The EP6D combines proportional electrical displacement control with a pressure cut-off function, allowing normal electronic flow control below the pressure limit and automatic destroking once the configured pressure command is reached.

7. DIN 5480 splined drive shaft

The Z code identifies a DIN 5480 splined shaft in the Rexroth A11VLO/A20VLO configuration system. For replacement engineering, this provides a clearly defined mechanical interface that must be matched to the original drive coupling.

8. Standard four-bolt mounting

The D code identifies the SAE J744 four-bolt mounting arrangement for the 190 size. This facilitates dimensional replacement verification but does not remove the need to check the exact pilot, shaft, port orientation and coupling arrangement.

9. High power density

At the published 350 bar condition, the A20VLO190 double pump is specified at 562 kW theoretical power. This illustrates why the 190 frame is intended for high-power hydraulic systems rather than light-duty auxiliary circuits.

10. Configuration-level replacement engineering

Two A20VLO190 pumps may share:

• Displacement
• Pressure rating
• Speed rating
• Basic housing platform

while still differing in:

• Control architecture
• Rotation
• Shaft
• Through-drive
• Electrical interface
• Pressure cut-off
• Power setting

Therefore, genuine interchangeability must be established from the complete model code rather than from A20VLO190 alone.

Application Areas

The A20VLO/A20VO Series 10 is documented for mobile and industrial applications, particularly systems requiring multiple hydraulic circuits.

Typical application environments include:

• Heavy construction machinery
• Large mobile hydraulic systems
• Multi-circuit hydraulic power systems
• Concrete machinery
• Excavation equipment
• Drilling machinery
• Cranes and lifting equipment
• High-flow industrial hydraulic systems
• Equipment requiring two independent variable hydraulic circuits

Historical Rexroth mobile-hydraulics material specifically references A20VO multi-circuit systems for excavators, cranes and drilling equipment, while the current RE 93100 maintains the multi-circuit/mobile/industrial positioning.

Final application compatibility should be verified against the original hydraulic schematic, prime-mover rating, shaft arrangement, rotation and control configuration.

Expert Maintenance Tips

1. Separate nominal pressure from maximum pressure

Use:

350 bar nominal pressure

and

400 bar maximum pressure

rather than advertising the unit simply as a “400 bar continuous pump.” Rexroth specifies a maximum-pressure single operating period of less than 1 second and a total operating period of 300 hours.

2. Control inlet pressure

For size 190, Rexroth specifies:

• Minimum inlet pressure: ≥0.6 bar absolute
• Maximum inlet pressure: ≤2 bar absolute

The minimum inlet pressure requirement is also dependent on speed and displacement.

Suction-line diameter, reservoir level, filtration restriction, oil temperature and viscosity therefore need to be checked together.

3. Keep case pressure within limits

For sizes 190 and 260, the maximum case pressure is 2 bar, and Rexroth requires a drain line to the reservoir. Case pressure must also remain controlled relative to inlet pressure.

4. Maintain hydraulic cleanliness

Rexroth’s current A11V(L)O documentation specifies a minimum cleanliness level of ISO 4406 20/18/15. If hydraulic-fluid viscosity falls below 10 mm²/s during short-term operation, the leakage-port cleanliness requirement increases to at least 19/17/14.

For replacement work, contamination control should therefore cover the reservoir, suction line, filters, control valves and actuators—not just the new pump.

5. Observe viscosity and temperature limits

For the NBR sealing configuration, the published permissible fluid temperature is up to +85°C in the normal operating range; FKM configurations are listed to +110°C. The optimal operating viscosity range is 36–16 mm²/s.

6. Follow the Rexroth startup sequence

For cold startup, the current control-system documentation allows:

• Viscosity up to 1600 mm²/s
• Maximum 3 minutes
• Pressure ≤50 bar
• Speed ≤1000 rpm

During warm-up:

• Viscosity 1600–400 mm²/s
• Maximum 15 minutes
• Pressure ≤0.7 × nominal pressure
• Speed ≤0.5 × nominal speed.

7. LE2E replacement must be tested as a power-control system

For A20VLO190LE2E, verify:

• Basic power setting
• Drive speed
• Maximum flow
• Electrical override current
• Power-reduction response
• Destroke behavior
• Stability under changing pressure

Rexroth’s LE2 documentation explicitly describes increasing control current as reducing the power setting.

8. EP6D replacement must be tested as an electro-proportional pressure-limited system

For A20VLO190EP6D, verify:

• 24 V electrical circuit
• Control-current response
• 200 mA beginning-of-control
• 600 mA end-of-control
• Pressure cut-off setting
• Destroke-to-Vgmin behavior
• Recovery after pressure decreases

The EP6D pressure cut-off setting range is 50–350 bar.

9. Check shaft torque and coupling

The Rexroth A11VLO control/shaft documentation provides maximum input torque limits by shaft type. For the 190-size DIN 5480 Z shaft, the published maximum input torque is 3140 N·m under the specified conditions.

Shaft alignment, spline condition, coupling geometry, torsional vibration and radial loading should all be checked during installation.

10. Verify the N00H-S suffix before final supply

For A20VLO190EP6D/10L-NZD24N00H-S, the current public type-code documentation confirms the main configuration positions but does not independently decode the full historical N00H-S suffix. Therefore, the final replacement should be released only after matching the original nameplate or Rexroth order/configuration record.

11. 100% simulated working-condition testing

For a verified replacement unit, the final test program should include:

Low-Speed Startup → Rated-Speed Operation → Full Displacement → Flow Verification → Pressure Build-Up → Control Response → Leakage → Temperature Rise → Sustained Load

For LE2E, the central acceptance criterion is:

Current → Power Setting → Displacement → Flow

For EP6D, it is:

Current → Displacement → Pressure Cut-Off → Destroke Response

This makes 100% simulated working-condition testing a measurable engineering deliverable rather than a generic marketing claim.

Technical Verification Summary

这次核验采用的核心依据是 Bosch Rexroth 官方出版物：

• RE 93100/2024-10-31 — A20VO, A20VNO, A20VLO series 10, Axial piston variable double pump
• RD 92500/2024-11-13 — A11V(L)O series 1x, Axial piston variable pump, which Rexroth’s A20VLO documentation explicitly references for the controls of sizes 95/190/260.

对于 A20VLO190，可以直接确认：

• 192.7 cm³/rev per rotary group
• 2500 rpm rated speed at Vgmax
• 350 bar nominal pressure
• 400 bar maximum pressure
• 2 × 482 L/min theoretical flow
• 562 kW theoretical power at 350 bar
• 2147 N·m theoretical torque
• 7.6 L case volume
• approximately 213 kg weight without through drive.

对于控制：

• LE2 family = power controller with electrically proportional override; Rexroth specifies 24 V, 200–600 mA control range, 0.77 A current limit, 22.7 Ω nominal resistance and 100 Hz dither.
• EP6D = proportional electric control with pressure cut-off; EP6 uses 24 V with manual override and spring return, while EP6D adds pressure cut-off in the 50–350 bar range.