Description
🔧 Product Overview
The BOSCH REXROTH QV45-RGC1 is a specialized analog amplifier card for proportional pressure and flow-control applications. Part number 0811405103 is associated with the Rexroth VT-VRPA1-527-1X/V0/QV-RTP amplifier family.
This European-format card is designed for proportional hydraulic valves and provides the electrical interface between a machine control signal and the hydraulic valve control circuit. Rexroth documentation identifies 0811405103 for 4WRP6EA and 3FREZ proportional valves. The card is designed for installation in the VT 3002-1-2X/32F open card holder.
The current listing identifies the item as Used, with Germany shown as the country of origin.
⚙️ Key Features
- Brand: Bosch Rexroth
- Model: QV45-RGC1
- Material Number: 0811405103
- Alternative Type: VT-VRPA1-527-1X/V0/QV-RTP
- Analog proportional-valve amplifier
- European-format plug-in circuit board
- 24 VDC operating supply
- 2.7 A solenoid output version
- Designed for proportional pressure/flow control valves
- Supports 4WRP6EA and 3FREZ valve applications
- Adjustable ramp function
- Zero-point adjustment
- Cable-break monitoring
- Front-panel status indication
- Suitable for VT 3002-1-2X/32F card holder
📋 Product Datasheet
| Parameter | Specification |
|---|---|
| Brand | Bosch Rexroth |
| Model | QV45-RGC1 |
| Material Number | 0811405103 |
| Type Code | VT-VRPA1-527-1X/V0/QV-RTP |
| Product Type | Amplifier Card / Circuit Board |
| Control Type | Analog |
| Application | Proportional pressure and flow valves |
| Supply Voltage | 24 VDC |
| Output Stage | 1 output stage |
| Solenoid Rating | 2.7 A |
| Valve Compatibility | 4WRP6EA / 3FREZ |
| Card Holder | VT 3002-1-2X/32F |
| Format | European plug-in card |
| Condition | Used |
| Country of Origin | Germany |
| Weight | Approx. 0.20 kg |
The 2.7 A output-stage designation and 24 VDC supply are documented for material number 0811405103. A service listing gives the board weight as approximately 0.20 kg.
🔌 Hydraulic Control System Integration
The QV45-RGC1 is not a general-purpose PLC output module. It is a dedicated hydraulic amplifier that converts the machine’s analog command signal into an appropriate electrical drive signal for a proportional hydraulic valve.
A typical control chain can be represented as:
Machine Controller → Analog Command → QV45-RGC1 → Valve Solenoid → Hydraulic Actuator → Machine Process
This arrangement allows the host controller to regulate hydraulic flow or pressure while the amplifier handles the electrical control of the proportional valve.
For replacement work, technicians should verify the complete hydraulic control loop, including:
- Controller output signal
- Supply voltage
- Valve model
- Solenoid rating
- Feedback arrangement
- Command polarity
- Card-holder configuration
- Existing wiring
- Ramp and zero-point settings
🎛️ Control & Adjustment Functions
The VT-VRPA amplifier family provides several front-panel adjustment and diagnostic functions.
Ramp Adjustment
The RTP version includes an adjustable ramp that can be switched off. The documented ramp timing range is approximately 0.05 to 5 seconds, allowing the hydraulic command to be increased or decreased in a controlled manner.
Zero-Point Adjustment
The front panel provides a zero-point adjustment of approximately ±10%. This can be used when setting the initial valve response during commissioning or replacement.
Sensitivity Adjustment
The amplifier includes an adjustable sensitivity range shown in the Rexroth documentation as approximately 50–100%.
Diagnostic LEDs
The documented front-panel indicators include:
- Green LED — Enable
- Red LED — Supply voltage below minimum
- Yellow LED — Ramp status
- Yellow LED — Cable-break indication
These indicators can help technicians distinguish between a supply problem, control enable issue, ramp setting, or possible signal/cable fault.
🧩 Valve Compatibility
Part number 0811405103 is specifically listed as:
VT-VRPA1-527-1X/V0/QV-RTP
The Rexroth documentation associates this version with 4WRP6EA and 3FREZ proportional valves.
The “527” designation corresponds to the 2.7 A solenoid version, while other VT-VRPA variants use different current ratings. Therefore, a visually similar Rexroth amplifier should not automatically be substituted.
Always match the amplifier to the actual valve coil and original machine configuration.
🏭 Typical Applications
The QV45-RGC1 can be encountered in industrial hydraulic systems requiring controlled proportional flow or pressure regulation, including:
- Hydraulic machine tools
- Industrial presses
- Forming equipment
- Hydraulic positioning systems
- Proportional valve control cabinets
- Flow-control systems
- Pressure-control systems
- Legacy Rexroth hydraulic machinery
- Specialized industrial automation equipment
The exact application depends on the valve, hydraulic circuit, controller, and machine configuration.
🛠️ Installation & Maintenance
Before installing a replacement amplifier card:
- Shut down the machine according to the manufacturer’s procedure.
- Isolate the 24 VDC control supply.
- Allow the control cabinet to reach a safe electrical state.
- Record the original card position and wiring.
- Verify the full 0811405103 / VT-VRPA1-527-1X/V0/QV-RTP identification.
- Check the valve coil rating before energizing the card.
- Inspect the card-holder contacts for contamination or oxidation.
- Confirm that all wiring is secure and correctly positioned.
- Reinstall the card without excessive mechanical force.
- Check the enable and supply indicators before applying the hydraulic command.
- Perform a controlled low-output test before returning the machine to normal operation.
Do not adjust the zero point, sensitivity, or ramp settings without recording the original values. Incorrect adjustment can change hydraulic machine response.
🔍 Troubleshooting
No valve response
Check the 24 VDC supply, enable signal, card seating, command signal, and valve-coil wiring.
Red supply LED is active
Verify the control supply and voltage at the amplifier. A low supply condition can prevent correct amplifier operation.
Cable-break indication
Inspect the command/feedback wiring associated with the valve control circuit and check terminals for loose or damaged connections.
Hydraulic movement is too abrupt
Check the ramp adjustment and compare it with the original machine settings. A shorter ramp produces a faster command transition.
Valve output is offset
Check the zero-point adjustment and verify that the hydraulic valve and mechanical system are correctly centered.
Replacement card does not work
Confirm that the replacement is actually 0811405103 / QV45-RGC1 and not another VT-VRPA variant with a different solenoid current or valve application.
🔐 Replacement Compatibility
For this component, part-number matching is especially important.
The 0811405103 amplifier belongs to a family containing multiple current ratings and valve configurations. For example, Rexroth documentation identifies 0811405102 as a 3.7 A version for different valve types, while 0811405103 is the 2.7 A QV version for 4WRP6EA / 3FREZ applications.
Before ordering a replacement, compare:
- QV45-RGC1 marking
- 0811405103 material number
- VT-VRPA type code
- Solenoid current
- Valve model
- Card-holder type
- Front-panel adjustment arrangement
- Machine wiring
This prevents installation of a physically similar amplifier with an incompatible electrical output stage.
❓ FAQ
Q1: What is Bosch Rexroth 0811405103?
It is a VT-VRPA-series analog amplifier card identified as QV45-RGC1 and intended for proportional pressure/flow valve control.
Q2: What voltage does the amplifier use?
The documented configuration uses a 24 VDC supply.
Q3: What is the output current?
The 0811405103 version is the 2.7 A solenoid configuration.
Q4: Which valves are associated with 0811405103?
Rexroth documentation identifies the card for 4WRP6EA and 3FREZ proportional valves.
Q5: Is QV45-RGC1 a PLC module?
No. It is a dedicated analog hydraulic amplifier card rather than a general-purpose PLC I/O module.
Q6: Which card holder is required?
The documented suitable card holder is VT 3002-1-2X/32F.
Q7: Is the listed unit new or used?
The referenced listing identifies the unit as Used.
Q8: Can another VT-VRPA amplifier replace it?
Only after verifying the valve type, solenoid current, ordering code, wiring, and complete machine configuration.
📦 Recommended Related Bosch Rexroth Models & Components
- BOSCH REXROTH 0811405100 — VT-VRPA1-527-1X/V0/RTP Amplifier Card
- BOSCH REXROTH 0811405101 — VT-VRPA1-527-1X/V0/PV-RTP Amplifier Card
- BOSCH REXROTH 0811405102 — VT-VRPA1-537-1X/V0/PV-RTP Amplifier Card
- BOSCH REXROTH 0811405104 — VT-VRPA1-537-1X/V0/QV-RTP Amplifier Card
- BOSCH REXROTH VT 3002-1-2X/32F — Open Card Holder
- BOSCH REXROTH VT-VRPA1-527-1X/V0/QV-RTP — Proportional Valve Amplifier
- BOSCH REXROTH 4WRP6EA — Proportional Valve Family
- BOSCH REXROTH 3FREZ — Proportional Flow-Control Valve Family
- BOSCH REXROTH VT-VRPA Series — Analog Valve Amplifier Family
- BOSCH REXROTH VT 3000 Series — Hydraulic Control Electronics
📌 Spare-Part Recommendation
For older Rexroth hydraulic systems, maintaining a correctly matched amplifier card as an onsite spare can significantly simplify troubleshooting and reduce downtime.
When stocking 0811405103, record the associated valve model, machine application, original adjustment settings, and card-holder configuration. This is particularly important because the VT-VRPA family contains different output-current versions.
The BOSCH REXROTH QV45-RGC1 0811405103 should therefore be purchased and installed as a configuration-specific hydraulic control component, with the amplifier’s current rating and valve compatibility verified before commissioning.
