Key Takeaways:
Marusaku hydrostatic rotary tables use a Heidenhain RCN2380 rotary encoder for closed-loop position feedback. Understand how encoder resolution and loop closure lock in ±0.001 mm accuracy.
The Measurement Link
A precision table needs to know where it is at all times. Marusaku hydrostatic rotary tables use a Heidenhain RCN2380 rotary encoder as the position sensor in a closed-loop control system.

Closed-Loop Principle
The controller commands a target angle; the encoder reports the actual angle; the difference is corrected continuously by the torque motor. This loop runs thousands of times per second, locking the table onto the commanded position.
Why RCN2380
The RCN2380 is a high-accuracy angle encoder built for demanding rotary axes. Its fine resolution and thermal-stable design suit the ±0.001 mm accuracy target of the hydrostatic table.
Result
Even if the oil film or load shifts slightly, the closed loop re-centers the table, so accuracy is maintained over long production runs rather than decaying.