When replacing BMMH 58S1N24C12/13Q25, the EncoderWorks custom compatible replacement should first control binary SSI cable integrity, IP67 sealing, and blind hollow-shaft seating. This model should not be treated as the Gray-code P25 version or as a through-hollow-shaft encoder. The electrical interface may look similar, but binary code, IP67 protection, and blind-shaft installation create different failure boundaries.
The BMMH 58S1N24C12/13Q25 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 Q25 suffix should be checked as an IP67, blind hollow-shaft, radial cable execution against the original label, cable route, and mounting drawing.
The first failure boundary is binary SSI decoding. Clock+ / Clock- and Data+ / Data- must remain true differential pairs from the encoder to the controller. If the controller is still configured for Gray code, or if the SSI frame length is shifted, the position value can be stable but wrong. Binary interpretation must therefore be confirmed before the machine is released.
This replacement fails when SSI communication is active, but the PLC reads the wrong multiturn value because cable pair assignment, binary-code interpretation, data termination, or SSI word length does not match the original encoder. The signal may be present while the decoded position is wrong.
The second boundary is IP67 blind hollow-shaft mounting. A blind hollow shaft is not a through bore. The machine shaft must enter to the correct depth, remain inside the clamping zone, and avoid bottoming inside the encoder. With IP67 sealing, self-heating and installation stress become more important, so torque support and shaft seating must be checked carefully.
Zero setting must also be protected. The zero input can shift the electrical reference within the encoder resolution. If it 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 Q25 suffix execution, blind hollow-shaft diameter, insertion depth, IP67 requirement, radial cable assignment, 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 58S1N24C12/13Q25 as an industrial encoder custom compatible solution where binary SSI cable integrity and IP67 blind-shaft mechanics decide field reliability.
Typical production lead time: 15 working days.
Key Data
| Item | Data |
|---|---|
| Model | BMMH 58S1N24C12/13Q25 |
| 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 |
| Connection | Radial cable |
| Protection class | IP67 |
| Control input | Zero setting input |
| Main engineering anchor | Binary SSI cable and IP67 blind shaft |
| Main failure boundary | Wrong binary decoding, SSI pair error, zero-set fault, blind-shaft seating error |
