EH Electro-Hydraulic Proportional Controller VT-3000BS30 VT3000BS30 VT-3OOOBS3O

Huade VT-3000BS30 | Analog Proportional Valve Amplifier Card — 24VDC, 32-Pin Euro Card, Series 30, PWM Output, For Huade WRZ Directional & DBEP6/3DREP6 Pressure Valves

Overview

The Huade VT-3000BS30 is a plug-in analog proportional valve amplifier card produced by Beijing Huade Hydraulic Industry Group — one of China's leading state-owned hydraulic component manufacturers, with a product portfolio spanning proportional valves, hydraulic pumps, motors, and control electronics.

The VT-3000BS30 is the signal conditioning and power amplification interface between an external control system (PLC, CNC, or process controller) and Huade's WRZ-type proportional directional valves and DBEP6/3DREP6 proportional pressure valves.

Beijing Huade's product development has maintained technical alignment with internationally recognised proportional valve standards.

The VT-3000 amplifier series shares functional architecture and naming conventions with the established Rexroth VT-3000 standard, which reflects Huade's engineering methodology of adopting proven design principles to ensure compatibility across the broader market of machines that use WRZ-type proportional hydraulic circuits.

In practice, the VT-3000BS30 is fully compatible not only with Huade's own proportional valve range, but also with Rexroth WRZ directional valves (up to component series 6X) and DBEP6/3DREP6 pressure valves — a practical advantage for maintenance teams and OEMs who work across both product families.

In a proportional hydraulic circuit, the amplifier card is the component that makes proportional control possible.

A proportional solenoid coil requires currents in the range of several hundred milliamperes to exert enough force to position the valve spool proportionally.

A PLC or controller output, by contrast, typically provides only a weak 0–10V or ±10V analog signal — nowhere near enough current to drive the solenoid directly.

The VT-3000BS30 receives the weak control signal, processes it through its ramp and step function circuitry, and delivers the correctly shaped, precisely regulated current to the solenoid coils through two PWM output stages.

Huade's VT-3000BS30 is found extensively in Chinese industrial machinery — metallurgical equipment, machine tools, press lines, mining machinery, engineering equipment, and hydraulic power units across industries where Huade's proportional valve range has been specified.

Given Huade's strong domestic market position and its long history of supplying Chinese state-owned enterprises in metallurgy, defence, and heavy industry, the VT-3000BS30 has become a standard maintenance item for facilities running Huade-equipped hydraulic systems throughout China and in markets where Chinese hydraulic equipment is deployed.

Key Specifications

Beijing Huade — Product Background

Beijing Huade Hydraulic Industry Group was established as part of China's development of independent hydraulic technology capability, and has grown into one of the country's largest dedicated hydraulic component manufacturers. Its core product lines — hydraulic control valves (directional, pressure, flow), axial piston pumps and motors, and proportional control electronics — cover the full range of industrial hydraulic system requirements. Huade's products are used in metallurgy, machine tools, military/defence equipment, shipbuilding, chemical processing, aerospace, engineering machinery, and construction equipment throughout China and internationally.

The VT-3000 amplifier series sits within Huade's proportional valve control electronics portfolio, designed to work in direct combination with the company's WRZ proportional directional valve family.

The VT-3000BS30 specifically serves the larger WRZ valve sizes (4WRZ10, 4WRZ16, 4WRE25, 4WRZ32) — pilot-operated, three-position, four-way proportional directional valves where the control electronics must drive two solenoid coils for bidirectional spool positioning without electrical position feedback.

How the VT-3000BS30 Controls a Proportional Valve

The proportional valve's spool position is determined by the net magnetic force from its two solenoid coils. Coil A drives the spool in one direction; coil B drives it in the other. At equilibrium (zero command), both coils are at minimum current (dither only) and the spool centres by spring force. A positive command activates coil A to a current proportional to the command magnitude; a negative command activates coil B.

The VT-3000BS30 performs this conversion in several stages. The input command signal (from PLC analog output, operator potentiometer, or preset reference) is fed to the summator, which combines it with any active preset command value from R1–R4. The ramp generator then smooths any step change in the summed signal, converting an abrupt input jump into a gradual ramp at the configured rate. The step function generator adds a brief current boost at the moment a command is activated, overcoming the valve spool's static friction to ensure immediate, clean movement without hesitation.

The resulting processed signal feeds the two current output stages, each driving one solenoid coil through PWM switching at 160–180 Hz.

The high-frequency switching current ripple (dither) keeps the spool in continuous micro-motion, preventing it from sticking in any position and ensuring smooth, repeatable positioning across the valve's full travel range.

Four Command Values and Relay Selection

One of the VT-3000BS30's most practical features for machine integration is its four pre-set command value architecture. Potentiometers R1 through R4 each define an independent command value — a specific spool position, flow rate, or pressure level corresponding to a predefined machine state. The machine's PLC selects between these four preset values by closing the corresponding relay contact (K1–K4).

LED indicators H1–H4 on the front panel confirm which command value is currently active.

This architecture is particularly suited to machines with discrete operating modes: press machinery that transitions between rapid approach, pressing force, holding pressure, and retraction; machine tool hydraulic clamping systems with defined clamp and unclamp positions; or material handling equipment with distinct slow and fast traverse speeds.

In these applications, the four pre-set command values eliminate the need for a true variable analog reference signal — the PLC simply selects the appropriate preset by contact output.

Relay K5 provides a ramp bypass input. When K5 is closed, the ramp generator is disabled and command changes produce instantaneous output transitions.

This is used when quick valve response is needed between already-ramped operating states — for example, emergency stops where gradual deceleration is less important than immediate valve response.

Installation, Wiring, and Operational Notes

The VT-3000BS30 mounts in a standard Euro card holder (Huade VT 3002-2X/32 single-card holder or equivalent). The 32-pin DIN 41612 connector provides all signal and power connections. Cardinal installation rules for reliable operation:

Power-off before insertion/removal. The card must never be inserted into or removed from the card holder with power applied.

The solenoid coil's inductance generates a back-EMF spike when the output is suddenly interrupted — sufficient to damage the card's output transistors if the output is live during hot-swap.

Signal and power cable separation. The command input signal cables (typically 0–10V or ±10V from the PLC) must be routed separately from the solenoid power wiring.

Running signal and solenoid cables in the same conduit introduces interference from the solenoid switching currents into the command signal path, producing unstable or oscillating valve behaviour.

Gold-contact relays for K1–K4. The relay contacts that select command values switch milliamp-level signal currents. Standard silver-contact relays develop contact resistance over time at these low currents.

Gold-plated contacts maintain consistent, near-zero contact resistance, ensuring reliable command value selection throughout the system's service life.

Slow-blow fuse only. The 5×20mm, 2.5A fuse must be a slow-blow type. A fast-blow fuse at the same current rating will trip on the inrush current when solenoids are first energised, causing nuisance interruptions. Always replace with the specified type.

FAQ

Q1: The VT-3000BS30 is a Huade product, but it is sometimes listed with Rexroth cross-references. Can it replace a Rexroth VT-3000 amplifier card directly?

For the valve compatibility: yes.

The VT-3000BS30 can drive Rexroth WRZ proportional directional valves (up to series 6X) and Rexroth DBEP6/3DREP6 pressure valves with the same functional result as the Rexroth VT-3000 card, because the solenoid electrical interface and operating principle are the same.

For the card holder and circuit interface: the 32-pin Euro card format and pin assignment follow the same standard, making physical substitution straightforward in most installations. Huade VT-3000BS30 units are widely used as replacement parts for VT-3000 cards in existing machines regardless of original valve brand, and this practice is well-established in the Chinese industrial maintenance market.

Q2: The card ships with a 5-second ramp time. How should it be adjusted for a faster machine cycle?

Jumpers J5 and J6 on the PCB switch the ramp time between the two factory-selectable values — typically 1 second and 5 seconds. Always change jumper settings with power removed and the card out of the holder.

Some variants support an external time potentiometer connected to the designated card pins for continuously adjustable ramp times between 0.03 and 5 seconds. Refer to Huade's VT-3000 technical documentation for the exact jumper and pin configuration for the BS30 variant.

Note that a faster ramp time produces sharper acceleration and deceleration in the hydraulic actuator, which may increase pressure peaks — verify that the hydraulic circuit's relief valve and pipe sizing can accommodate the increased rate of pressure rise.

Q3: What do the H1–H4 LEDs indicate, and how should they be used for fault diagnosis?

LED H1 through H4 illuminate to show which of the four command values (R1–R4) is currently selected via the K1–K4 relay inputs. During normal operation, exactly one LED should be illuminated at a time, corresponding to the active machine state.

If no LED is on, no command value is selected and the output is at zero (spool centred, no flow).

If multiple LEDs are on simultaneously, multiple relay contacts are closed and the corresponding command values are summed — this is usually unintended and produces an incorrect valve position.

An illuminated fault alarm LED (separate from H1–H4) indicates the card has detected an internal fault condition and the output has been disabled.

Q4: The card includes a step function generator. Under what circumstances should it be adjusted or disabled?

The step function generator provides a brief current overshoot when a command value is first selected, helping the valve spool overcome static friction and move cleanly through the dead zone. In most standard applications, the factory setting should not need adjustment.

If the machine exhibits a brief pressure spike or velocity overshoot at the moment a valve command is applied — suggesting the step function is too aggressive — the step amplitude can be reduced.

If the machine shows hesitation or dead zone at command transitions — suggesting insufficient step function — the amplitude can be increased.

Disable the step function only when the hydraulic circuit is particularly sensitive to any transient current overshoot, such as very low-pressure precision circuits.

Q5: Huade's VT-3000BS30 is used for Huade's WRZ valves. How does it differ in application from the VT-3013BS30 and VT-3014BS30 also in the Huade VT-3000 family?

Within Huade's VT-3000 amplifier range, different suffix variants serve different valve types in the product line.

The VT-3000BS30 is designed for larger pilot-operated WRZ proportional directional valves (4WRZ10 through 4WRZ32) and for DBEP6/3DREP6 pressure valves. 

The VT-3013BS30 and VT-3014BS30 are configured for the direct-operated 4WRA6 and 4WRA10 proportional directional valves — smaller, direct-drive valves with different solenoid current requirements and dynamic characteristics than the pilot-operated WRZ range.

Always verify the valve type and its solenoid specification against the amplifier variant before substitution; using the wrong VT-3000 variant for a given valve type will result in incorrect current levels and potentially unstable or unresponsive valve behaviour.