A completed hydraulic power unit is not ready for full-load operation merely because its motor starts. Commissioning should confirm wiring, fluid condition, relief protection, actuator movement and the response to faults in a controlled order.
Move from inspection to measured operation
Start with the approved schematic, component ratings and installation drawings. Verify fluid identity and fill level, hose connections, rotation direction, electrical interlocks and accessible isolation. Vent trapped air by the method specified for the actual equipment. Parker’s valve operating instructions describe low-pressure, no-load functional movement after air bleeding and a second venting check. The exact sequence must follow the machine risk assessment and supplier instructions.
Engineering checks
- Confirm guards, supports and emergency-stop functions before motion.
- Record baseline oil cleanliness, temperature and filter condition.
- Check pump inlet and outlet pressure without exceeding ratings.
- Move each actuator slowly through a controlled cycle.
- Test agreed alarms, load holding and power-loss behavior.
Common mistake to avoid
Increasing the relief setting to overcome a stalled actuator can hide a closed valve, trapped air or a mechanical obstruction. Find the cause before raising pressure.
Data to send with an inquiry
- Approved hydraulic and electrical schematics.
- Commissioning test pressures and acceptance criteria.
- Sensor calibration and alarm set points.
- Signed record of measured values and open defects.
Finish with representative load testing, a corrected as-built record and an operator handover. For related selection guidance, see our HPU sizing from duty cycle.
Field note
Before the first loaded cycle, compare recorded pump rotation, relief settings and sensor scaling with the approved drawings. Keep an exception list for any deviation. A witnessed handover is more useful when it identifies the actual measurement conditions and the person responsible for closing each exception.
Technical references: Parker D1VW operating instructions; Bosch Rexroth hydraulic power-unit overview. Cover: original conceptual schematic, not a product photograph.