Valve Response Time
This is the time elapsed from the moment the command changes until the valve spool reaches most of its new position. On directly driven proportional valves it is typically 30-80 ms, and on large pilot operated valves it goes above 100 ms; this time determines how agile the system feels.
Response time is not a single number but the sum of a chain. The remote control sending the signal, the driver raising the current, the coil building its magnetic field, the spool moving against spring and friction, and finally the oil reaching the actuator. The slowest link in the chain determines the total.
- Coil inductance limits how fast current can rise; that is why drivers apply a high voltage at the first instant to build current quickly.
- On pilot operated valves the pilot oil driving the main spool also has to travel, which adds tens of milliseconds.
- Long hose runs and air in the oil create additional delay on the mechanical side.
On AXI's HCT400 and HCT402 kits, the end-to-end command execution time is stated as under 1 second; on the HCT402, Dynamic mode makes this response sharper than Soft mode. Remember that part of the total perceived delay belongs to the vehicle's own valve: even if the kit gets faster, the hydraulic side's own time stays where it is.
Where this term is used: What Does the HCT402 Achieve, How, and How Much? A Technical Review