R900928873 DRE6-1X/21OMG24K4M German Rexroth proportional pressure reducing valve

FAQ:

1. High Reduced Pressure Rating (210 bar)

   The "210"​ denotes the maximum electrically adjustable reduced pressure​ at port A. The inlet at port P can be up to 315 bar, but the valve will regulate port A to a maximum of 210 bar. This is the high-pressure variant​ of the DRE6 series (compared to the 100 bar and 50 bar versions).

2. Requires External Amplifier

   Unlike the DREE series with integrated electronics (OBE), the DRE6​ series requires an external proportional amplifier​ (e.g., Rexroth VT-5000 series). The valve's coil is driven by the amplifier, which accepts the command signal (0–10 V or 4–20 mA). The "M"​ in the code indicates a standard proportional solenoid coil.

3. 3-Way Function (P, A, T)

   This valve has three working ports: P​ (inlet), A​ (reduced pressure outlet), and T​ (tank). It continuously compares the A-port pressure with the electrical setpoint. If A-port pressure is too high, it opens a path to T to bleed off excess pressure and maintain the set value.

4. Pilot-Operated Design

   This is a pilot-operated valve, not a direct-operated poppet. It uses a small pilot flow (approx. 0.65 L/min) for control, which allows for higher main flow capacity (30 L/min) and faster response compared to direct-operated valves.

5. Critical Installation Notes

   • External Amplifier Needed:​ You must use an external amplifier card to drive the valve. The K4 connector on the valve only carries coil power from the amplifier.

   • Tank Line Backpressure:​ Port T must be connected directly to tank with minimal backpressure. High backpressure at T will be added to the A-port pressure, causing inaccurate regulation.

   • Pilot Flow:​ Ensure your system can supply the small pilot flow required for the valve's internal operation.