3500/40M 135489-04 is the 3500/40M Proximitor I/O Module with internal barriers and internal terminations. It combines the rear four-channel signal interface with the barrier construction required by its documented installation class.

Compared with the standard I/O module, the barrier version has a deeper enclosure, a different operating-temperature range and a higher module weight. These distinctions must remain visible during spare selection.

• Combines four-channel Proximitor I/O with integrated internal barriers.
• Uses internal field terminations at the rear of the 3500 rack.
• Provides the required signal path and -24 V DC transducer power for the paired monitor.
• Uses a 163.1 mm deep enclosure distinct from standard non-barrier I/O.
• Supports the configured vibration or position functions of the 3500/40M monitor.

• Radial vibration monitoring on rotating machinery with proximity transducers.
• Thrust-position and shaft-position protection within a 3500 rack.
• Differential-expansion or eccentricity channels configured in supported pairs.
• REBAM channels where the required monitor firmware and rack software are installed.
• Machinery-protection retrofits that retain the documented 3500/40M channel strategy.

• Confirm that 3500/40M 135489-04 is required as the barrier I/O version before ordering.
• Retain the internal-termination wiring plan and the paired monitor position.
• Review hazardous-area documentation and site approvals before any module change.
• Do not apply the -30 °C lower operating limit of standard I/O; the barrier module is specified from 0 °C.
• Test every connected channel and protective function after installation.