A custom compatible replacement for BMMH 58S1G24C12/13QBA can be supplied by EncoderWorks with the main check placed on Gray-code SSI M23 mapping, IP67 sealing, and Ø15 mm blind hollow-shaft seating. This model should not be treated as a through-hollow-shaft encoder. The QBA suffix changes the replacement focus toward sealed blind-shaft mechanics, connector pin assignment, and temperature behavior under IP67 operation.
The BMMH 58S1G24C12/13QBA is a magnetic SSI multiturn absolute encoder configuration with 12-bit singleturn resolution, 13-bit multiturn range, Gray code, and 10–30 VDC SSI supply. The QBA suffix should be verified as an IP67, Ø15 mm blind hollow shaft, radial M23 connector execution against the original label and installation drawing.
The first failure boundary is IP67 blind-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, installation stress and self-heating are more important, so poor shaft seating or torque-support preload can create unstable feedback after runtime.
This replacement fails when SSI communication is active, but the machine position becomes unstable because the Ø15 mm blind shaft is bottomed, under-inserted, or loaded by a misaligned torque support. The fault may look like SSI noise, while the first failure is mechanical.
The second boundary is M23 SSI pin mapping. Clock+ / Clock- and Data+ / Data- must remain true differential pairs from the encoder to the controller. The M23 connector also carries supply, 0 V, zero input, and unused contacts. If the SSI pairs are crossed, shield bonding is weak, or an unused contact is connected, the controller may read shifted or intermittent multiturn values.
Zero setting must be protected during installation. A low impulse on the zero input can shift the electrical reference within the encoder resolution. If this line is triggered unintentionally, the SSI word can remain stable while the machine zero is wrong.
The replacement decision should first confirm QBA suffix execution, Ø15 mm blind hollow-shaft fit, insertion depth, IP67 requirement, radial M23 connector layout, 10–30 VDC SSI supply, 12-bit singleturn and 13-bit multiturn mapping, Gray code setting, Clock/Data differential pair wiring, 120 Ω data termination, zero input behavior, shield grounding, torque support, and shaft seating. EncoderWorks treats BMMH 58S1G24C12/13QBA as an industrial encoder custom compatible solution where M23 SSI mapping and IP67 blind-shaft mechanics decide field reliability.
Typical production lead time: 15 working days.
Key Data
| Item | Data |
|---|---|
| Model | BMMH 58S1G24C12/13QBA |
| Encoder type | Multiturn absolute encoder |
| Interface | SSI |
| Sensor technology | Magnetic |
| Resolution | 12-bit singleturn + 13-bit multiturn |
| Code | Gray |
| 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 | IP67 |
| Control input | Zero setting input |
| Main engineering anchor | Gray SSI M23 and Ø15 blind shaft |
| Main failure boundary | Wrong M23 pin mapping, zero-set error, blind-shaft seating error, IP67 preload |
