R900500255 DR20-4-5X/200YM Rexroth stacked pressure reducing valve made in Germany

Frequently Asked Questions (FAQ) for Rexroth DR 20-4-5X/200YM (R900500255)

Q1: What is the main function of this valve?

A:​ It is a proportional pressure reducing valve​ for larger hydraulic systems. It electronically controls and maintains a precise, stable pressure (up to 200 bar) in a subsystem, regardless of the primary circuit's pressure.

Q2: What is the key difference between the "200YM" and a "315YM"?

A:​ The "200" specifies the maximum adjustable reduced pressure​ is 200 bar. The "315YM" model can be set up to 315 bar. Otherwise, the "YM" (proportional control) function is identical.

Q3: What does the "NG 20" size mean?

A:​ "NG 20" is the Nominal Size 20. It indicates a larger valve with larger flow passages, designed for flows up to approximately 250 liters per minute​ (significantly higher than an NG10 valve at ~80 l/min).

Q4: How is it installed?

A:​ It is a sandwich valve. It mounts between a NG20 subplate​ (e.g., Rexroth RE 20 series) and another valve or cover plate, forming a modular manifold block for high-flow circuits.

Q5: How is the pressure controlled?

A:​ It is controlled by a standard PWM signal​ (typically 24V DC) via its integrated proportional solenoid with onboard electronics (OBE), requiring a compatible amplifier or controller card.