ZWO Electronic Automatic Focuser EAF Pro The ZWO EAF Pro 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 Electronic Automatic Focuser EAF Pro · Specifications checked against manufacturer data on 2026-11-03
The ZWO EAF Pro 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.
EAF Pro adds Bluetooth 5.0, a built-in lithium battery, body focus buttons, a power switch and status indicator. USB Type-C supplies 5 V at 500 mA when connected. ZWO’s endurance test achieved seven 8-hour nights at room temperature with two focusing operations per hour; this is a test condition rather than a guaranteed runtime.
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.
For wireless ASIAIR operation, ZWO lists the Plus RK version and ASIAIR camera series. Original ASIAIR, Pro, Mini and Plus CM4 versions are excluded from that Bluetooth compatibility list. 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; Bluetooth 5.0 |
| 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 |
| Battery | Built-in lithium; manufacturer lists 5 V 2.5 Ah |
| Manual controls | Integrated focus buttons; power switch; status light |
| Battery endurance | Up to 7 nights in ZWO test: room temperature, 2 focus operations per hour, 8 hours/night |
| Battery charging temperature | 0–45 °C |
| Battery discharging temperature | −10 to 40 °C |
| Wireless asiair compatibility | ASIAIR Plus RK version (IC suffix ASIAIRPLUS); ASIAIR camera series |
| Wireless asiair exclusions | Original ASIAIR; ASIAIR Pro; ASIAIR Mini; ASIAIR Plus CM4 version (IC suffix RPICM4) |
Data sheet
ZWO Electronic Automatic Focuser EAF Pro The ZWO EAF Pro 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 Electronic Automatic Focuser EAF Pro · Specifications checked against manufacturer data on 2026-11-03
