ZWO EAF N Electronic Automatic Focuser The ZWO EAF N drives a telescope focuser with a compact stepper motor and 1:128 reduction. ZWO specifies a 5 kg payload and approximately 2.812 µm positioning per step under its stated setup; linear movement depends on the focuser mechanism.
Manufacturer model: ZWO EAF N Electronic Automatic Focuser · Specifications checked against manufacturer data on 2026-11-03
The ZWO EAF N drives a telescope focuser with a compact stepper motor and 1:128 reduction. ZWO specifies a 5 kg payload and approximately 2.812 µm positioning per step under its stated setup; linear movement depends on the focuser mechanism.
A USB Type-C connection supplies 5 V at 500 mA and carries wired control. This model has no integrated battery or Bluetooth. The increased motor power requirement means the original ASIAIR and ASIAIR Pro are not supported by ZWO’s stated USB compatibility guidance.
The focuser supports ASIAIR, ASIStudio, ASCOM and INDI-compatible workflows. The 3.5 mm accessory connection accepts a compatible hand controller or temperature probe, available separately.
Fit the correct bracket and flexible coupling to the focuser shaft. ZWO advises a 4 mm coupling for the listed Takahashi and Celestron C8/C11 configurations, rather than the 5 mm coupling. Set backlash, zero and travel limits before automated use.
ZWO manufacturer documentation
Use the exact named-model manufacturer connection and operating instructions linked with this product. Optional parts and adapters require their specified spacing and power limits.
| Step angle (°) | 7.5 |
|---|---|
| Reduction ratio | 1:128 |
| Manufacturer step resolution | Approximately 2.812 µm per step; depends on focuser installation |
| Communication | USB Type-C |
| USB power | 5 V, 500 mA |
| Accessory port | 3.5 mm temperature-probe / hand-controller interface |
| Coupling note | Takahashi and Celestron C8/C11 installations: use 4 mm coupling; manufacturer advises against 5 mm coupling |
| Asiair power compatibility | Not compatible with first-generation ASIAIR or ASIAIR Pro USB output capability; manufacturer recommends newer-generation ASIAIR |