R900770685 DBW10A1-5X/350-6EG24N9K4 German made Rexroth electromagnetic relief valve
Professional electromagnetic relief valve with integrated solenoid unloading function for industrial hydraulic systems.
Frequently Asked Questions (FAQ)
Q1: What is the difference between DB10 and DBW10?
DB is a pilot relief valve only – limits system pressure. DBW adds an integrated directional solenoid valve: when energized the main stage is unloaded (P→T open, near 0 bar); when de-energized it works as a normal relief valve at the set pressure.
Q2: What does "A1" and "/350" mean?
• A1 = subplate mounting (NG10), adjustment by hexagon socket with protective cap (Allen key).
• /350 = spring pressure stage, maximum adjustable relief pressure = 350 bar (highest standard stage for Size 10 DB/DBW).
Q3: How do I adjust the relief pressure?
With system depressurized, remove the protective cap, turn the setscrew with an Allen key – clockwise to increase, counterclockwise to decrease. Factory preset is typically near minimum of the spring range. Reinstall cap and verify with a pressure gauge. The solenoid does NOT change the set pressure.
Q4: What is the solenoid logic?
Standard: Solenoid DE-energized = relief active at set pressure. Solenoid ENERGIZED = system unloaded (P connected to T). Confirm this matches your PLC/logic before wiring.
Q5: Which subplate and electrical connector are needed?
• Subplate: standard NG10 (ISO 6264) with P and T ports (G 1/2" or M18×1.5 on subplate), four M10 bolts @ ~35-40 N*m.
• Electrical: EN 175301-803 Form A (DIN 43650-A) 3-pin + PE connector, 24 V DC. If the plug has an LED, observe (+) / (-) polarity on the plug.
Q6: Common faults & causes?
• Solenoid clicks but no unloading: pilot orifice clogged, main spool stuck, no coil current (check ~18-28 Ω), manual override jammed.
• Pressure won't reach set value / creeps early: wrong spring (not /350), pilot damping hole blocked, contaminated pilot seat, excessive T-backpressure (internal pilot drain).
• Coil overheats / burnt smell: overvoltage (>10% above 24V), wrong voltage coil, or mechanical damage – replace only with correct G24 wet-pin coil.
• Chatter / unstable: air in system, high T-backpressure, worn pilot seat – bleed air first.
Q7: Does T-port backpressure affect set pressure?
Yes – this model has internal pilot drain. Backpressure at T adds 1:1 to the relief setpoint. If your tank line has >5 bar sustained backpressure, consider the DBW…Y version (external pilot drain to separate tank line).
Q8: Fluid & seal compatibility?
NBR seals = mineral oil (HL/HLP) & HFC (water-glycol). For HEES/HETG biodegradable oils or HFD phosphate ester → specify FKM (Viton) seal variant. Maintain oil cleanliness per ISO 4406 code 18/16/13 or better.
Need the Rexroth DB/DBW series datasheet (RE 25802) or NG10 subplate machining dimensions? Just let me know.