Size 21 Optical Encoders
Allied Motion’s S21 series are cost-effective, hollow shaft modular optical encoders that are easy to mount and offer both incremental and absolute output formats. These compact, standard size 21 (2.1 in diameter) encoders have their own bearing system and are housed in a high-grade glass filled plastic resin shell with an IP40 protection rating.
The S21 series' features include up to 10,000 RPM shaft speed, software configurable resolution, and eight format types including sine-cosine, high-count incremental (to 2.1 million CPR), and serial and parallel absolute versions.
The table below summarizes the performance of the S21 encoder series.
| Series | Frame Size mm | Length mm | Type | Format | Resolution | Frequency Response MHz | Product Information |
|---|---|---|---|---|---|---|---|
| S21A | 53 | 31 | Incremental | Sine/Cosine | 1000, 1024, 4096 | 0.1 | |
| S21B | 53 | 31 | Absolute | Serial, SSI binary | 8 - 16-bit binary | 5 | |
| S21C | 53 | 31 | Incremental | BISS C | 2000 - 2,048,000 | 5 | |
| S21D | 53 | 31 | Incremental | Digital | 1000 - 409,600 | 0.5 | |
| S21G | 53 | 31 | Absolute | Serial, SSI Gray code | 8 - 16-bit Gray code | 0.3 | |
| S21H | 53 | 31 | Incremental | Serial, SSI Gray code | 8 - 16-bit Gray code | 1.5 | |
| S21P | 53 | 31 | Absolute | Parallel, Gray code | 13-bit Gray code | 0.3 | |
| S21W | 53 | 31 | Incremental | Digital w/ commutation | 2048 - 204,800 | 0.5 |