# ZeroErr eCoder65 RS485 Absolute Magnetic Ring Encoder, 65 mm Bore

![ZeroErr eCoder65 RS485 Absolute Magnetic Ring Encoder, 65 mm Bore](https://parts.trymaglev.com/img/ac-zeroerr-ecoder65.webp)

ZeroErr's 65 mm bore ring encoder with a 77° arc readhead for large hollow joints (shoulder, hip, waist).

- Maglev ID: ac-zeroerr-ecoder65
- Brand: ZeroErr
- MPN: eCoder65
- Category: actuators / Magnetic Encoders
- Origin: CN (maker HQ, factory not confirmed)
- Maker: ZeroErr (brand, CN)
- NDAA: unknown · Blue UAS: unknown · FCC: n/a
- HTS: 9031.80.80.85 (typical)
- MOQ: unknown · Lead time: unknown
- Confidence: REPORTED

## Price
- 1+: $330 (distributor, 2026-10-30, https://aifitlab.com/products/zeroerr-ecoder65-magnetic-encoders; single-turn RS485 variant; backordered)

## Specifications
- Resolution: 20 bit (ZeroErr product page); family 17-21 bit + optional 16-bit multiturn counter (manual)
- Accuracy: <0.04° maximum absolute tolerance with well-centred ring (manual Table 7-1); self-calibration recommended after install; repeatability ±5"
- Max speed: 6,000 rpm
- Interface: RS-485 asynchronous serial, 2.5 Mbps (request/response frames with CRC)
- Form: off-axis ring kit (axial-reading magnetic ring + readhead)
- Sensing: unknown
- Supply: 4.7-5.4 V
- Bore: 65 mm ring ID (readhead ID 70 mm)
- Outer diameter: 84 mm ring OD; readhead OD 96 mm
- Multi-turn: yes, optional 16-bit multiturn counter with 3.6 V battery backup (eCoder xx M-RxxB)
- Operating temp: -40 to +70 °C (product page); manual says -40 to +105 °C

## Links
- Product: https://aifitlab.com/products/zeroerr-ecoder65-magnetic-encoders
- Datasheet: none
- CAD: none

## Equivalents
- RLS AksIM-2 Off-Axis Absolute Rotary Encoder (ac-rls-aksim-2)
- Renishaw RESOLUTE Rotary Readhead, BiSS 32-bit, 150 mm Ring (ac-renishaw-resolute-ra32bba150b30f)
- KingKong MPP Series Large-Size Joint Magnetic Encoder (ac-kingkong-mpp)

## Sources
- https://aifitlab.com/products/zeroerr-ecoder65-magnetic-encoders (variants, price, <0.04° tolerance, ±5" repeatability, dimensions, stock)
- https://www.zeroerr.com/magnetic_encoders/ecoder65 (maker page: ID/OD, 20 bit, repeatability, 6000 rpm, RS485, temperature)
- https://dl.zeroerr.cn/static/en/ZeroErr_eCoder_Manual_Ver2.6.pdf (eCoder manual v2.6: accuracy table, supply 4.7-5.4 V, 17-21 bit, multiturn battery, 2.5 Mbps RS485)