A custom compatible replacement for BMMH 58S1N24C12/13B2A can be supplied by EncoderWorks with the main check placed on binary SSI M23 mapping, Ø15 mm blind hollow-shaft seating, and 10–30 VDC signal compatibility. This model should not be treated as the Gray-code version with the same mechanical appearance. The shaft and connector may fit, while the controller still decodes the wrong position because binary word interpretation, SSI frame length, or zero input behavior is different.
The BMMH 58S1N24C12/13B2A is a magnetic SSI multiturn absolute encoder configuration with 12-bit singleturn resolution, 13-bit multiturn range, binary code, and 10–30 VDC SSI supply. The B2A suffix should be checked as a radial M23 connector execution with Ø15 mm blind hollow shaft against the original label, installed connector, and mounting drawing.
The first failure boundary is binary SSI decoding. Clock+ / Clock- and Data+ / Data- must remain true differential pairs, and the controller must read the same 12/13-bit SSI frame as before. If the receiver is still configured for Gray code, or if the frame length is shifted, the position value can be stable but wrong.
This replacement fails when SSI communication is present, but the PLC reads the wrong multiturn position because M23 pin mapping, Clock/Data pair assignment, binary-code interpretation, or SSI word length does not match the original encoder. The encoder may be functional while the signal chain is wrong.
The second boundary is Ø15 mm blind hollow-shaft seating. A blind hollow shaft is not a through bore. The machine shaft must enter to the correct depth, stay inside the clamping zone, and avoid bottoming inside the encoder. Incorrect insertion can preload the bearing system or reduce clamping reliability.
Zero setting must also be protected. The zero input can shift the electrical reference within the encoder resolution. If this line is triggered during wiring or tied to the wrong level, the controller can receive a clean but offset binary position value.
The replacement decision should first confirm B2A suffix execution, Ø15 mm blind hollow-shaft fit, insertion depth, radial M23 connector layout, IP65/IP67 requirement, 10–30 VDC SSI supply, 12-bit singleturn and 13-bit multiturn mapping, binary code setting, Clock/Data differential pair wiring, 120 Ω data termination, zero input behavior, shield grounding, torque support, and shaft seating. EncoderWorks treats BMMH 58S1N24C12/13B2A as an industrial encoder custom compatible solution where binary SSI mapping and Ø15 blind-shaft mechanics decide field reliability.
Typical production lead time: 15 working days.
Key Data
| Item | Data |
|---|---|
| Model | BMMH 58S1N24C12/13B2A |
| Encoder type | Multiturn absolute encoder |
| Interface | SSI |
| Sensor technology | Magnetic |
| Resolution | 12-bit singleturn + 13-bit multiturn |
| Code | Binary |
| Supply voltage | 10–30 VDC |
| Signal standard | SSI clock input, RS422 data output |
| Shaft type | Blind hollow shaft, not through hollow |
| Shaft size | Ø15 mm |
| Connection | Radial M23 connector |
| Protection class | Verify IP65 / IP67 execution |
| Control input | Zero setting input |
| Main engineering anchor | Binary SSI M23 and Ø15 blind shaft |
| Main failure boundary | Wrong binary decoding, M23 mapping error, zero-set error, blind-shaft seating error |
