A custom compatible replacement for GXP2W.B40B1A2 can be supplied by EncoderWorks with the main check placed on SSI data-pair integrity, radial M23 pin mapping, and Ø6 mm IP65 synchro-flange alignment. This model should not be handled like the Ø10 mm clamping-flange version. The smaller synchro shaft makes coupling accuracy more sensitive, while the SSI interface still depends on stable Clock+/Clock- and Data+/Data- transmission.
The GXP2W.B40B1A2 is an SSI multiturn absolute encoder with optical sensing, 13-bit singleturn resolution, 12-bit multiturn range, 8192 steps per turn, 4096 turns, 10–30 VDC supply, SSI RS485 data output, RS232 programming interface, Ø58 mm housing, Ø6 mm synchro flange, IP65 shaft-seal execution, and B1 radial M23 16-pin connector.


The first failure boundary is SSI pair wiring. Clock+/Clock- and Data+/Data- must be assigned as differential signal pairs, not treated as ordinary single-ended conductors. If the M23 connector is wired by pin position only and the differential pairs are crossed, the controller may still receive data but with intermittent bit errors, shifted position words, or speed-related read instability.
This replacement fails when SSI communication is active, but the PLC reads unstable multiturn position values because the clock pair, data pair, cable shielding, or SSI clock frequency does not match the original installation. That is a timing and signal-integrity failure, not an encoder sensing failure.
The second boundary is programmed parameter agreement. Total resolution, Gray or binary code, rotating direction, preset, offset, and zero point can be changed through the programming interface. If those settings are not copied, the controller can receive a clean SSI word while the absolute position no longer matches the machine.
Mechanically, the B shaft option means Ø6 mm synchro flange with IP65 protection. This smaller shaft should not be used to correct coupling eccentricity or flange misalignment. Axial and radial shaft-load limits are installation boundaries, not preload targets. The radial connector also needs cable clearance so connector strain does not influence shaft alignment.
The replacement decision should first confirm Ø6 mm synchro-flange geometry, IP65 shaft-seal requirement, B1 radial M23 pin assignment, SSI Clock+/Clock- and Data+/Data- pairing, 13-bit singleturn and 12-bit multiturn mapping, Gray/binary code setting, UP/DOWN direction, preset behavior, RS232 programmed parameters, supply voltage, shielding, and coupling load. EncoderWorks treats GXP2W.B40B1A2 as an industrial encoder custom compatible solution where SSI data pairing and synchro-flange mechanics decide field reliability.
Typical production lead time: 15 working days.
Key Data
| Item | Data |
|---|---|
| Model | GXP2W.B40B1A2 |
| Encoder type | Multiturn absolute encoder |
| Interface | SSI |
| Sensor technology | Optical |
| Resolution | 13-bit singleturn + 12-bit multiturn |
| Steps / turns | 8192 steps per turn / 4096 turns |
| Code | Gray or binary, programmable |
| Supply voltage | 10–30 VDC |
| Housing | Ø58 mm steel housing |
| Shaft / flange | Ø6 mm synchro flange |
| Protection class | IP65 with shaft seal |
| Connection | B1 radial M23 16-pin connector |
| Programming interface | RS232 |
| Main engineering anchor | SSI data pairing and synchro flange |
| Main failure boundary | Wrong SSI pair wiring, code mismatch, preset error, coupling preload |

