Temposonics RHM Series Modules

Technical Dossier

Product Details And Specifications

MTS Temposonics RHM Series: Comprehensive Module Range and Technical Overview

The MTS Temposonics RHM series represents one of the most widely deployed families of magnetostrictive linear position sensors in global heavy industry. Installed across petrochemical refineries, nuclear power stations, offshore platforms, hydraulic press systems, and continuous casting lines, the RHM profile sensor is the standard reference for absolute, non-contact linear position measurement in demanding environments. The RHM form factor — a rigid aluminum extrusion housing — is engineered for direct integration into hydraulic cylinders and linear actuator assemblies, operating reliably under sustained vibration, EMI exposure, and temperature extremes from -40°C to +75°C. Measurement strokes range from 25 mm to 7620 mm, with resolution down to 1 µm and linearity within ±0.02% FSO, making the RHM series the preferred choice for closed-loop feedback in safety-critical process control.

The Evolution of Temposonics RHM Architecture

MTS Sensors introduced the Temposonics product line in the 1970s, establishing the magnetostrictive measurement principle as the industrial standard for absolute linear position feedback. The RHM series (Rigid Housing, Metric) emerged as the primary profile-style sensor, replacing earlier rod-style designs in applications requiring external mounting and direct cylinder integration.

Early RHM variants used analog voltage (0–10 V) and current (4–20 mA) outputs, interfacing directly with legacy DCS analog input cards. As fieldbus adoption accelerated through the 1990s and 2000s, MTS introduced SSI (Synchronous Serial Interface), Start/Stop, and PWM output variants, enabling direct connection to Siemens, Allen-Bradley, Bosch Rexroth, and Beckhoff motion controllers without intermediate signal conditioning. The current generation supports CANopen, PROFIBUS-DP, EtherNet/IP, PROFINET, and EtherCAT, covering the full spectrum of modern industrial network architectures. Backward compatibility within the RHM mechanical envelope allows direct replacement of legacy analog units with digital-output variants without hydraulic system modification — a critical factor for brownfield plant upgrades.

Temposonics RHM Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly stocked RHM series part numbers. Each model is identified by stroke length, output type, and connector configuration encoded in the MTS part number structure.

RHM0165MD631P102: 165 mm stroke, SSI output, 25-pin D-sub connector, synchronous serial interface for direct PLC/controller integration.
RHM0250MD631P102: 250 mm stroke, SSI output, standard profile housing, high-resolution absolute position feedback.
RHM0500MD631P102: 500 mm stroke, SSI output, rigid aluminum extrusion, suitable for mid-range hydraulic cylinder feedback.
RHM0750MD631P102: 750 mm stroke, SSI output, extended range for large-bore actuator applications.
RHM1000MD631P102: 1000 mm stroke, SSI output, 1-meter range for press and forming machine integration.
RHM0165MR101P102: 165 mm stroke, analog 4–20 mA output, direct DCS analog input card compatibility.
RHM0250MR101P102: 250 mm stroke, analog 4–20 mA output, two-wire current loop, intrinsically safe variants available.
RHM0500MR101P102: 500 mm stroke, analog 4–20 mA output, standard for legacy PLC analog input modules.
RHM0165MP101P102: 165 mm stroke, Start/Stop pulse output, compatible with Bosch Rexroth and Parker motion controllers.
RHM0250MP101P102: 250 mm stroke, Start/Stop output, widely used in injection molding machine retrofits.
RHM0165MD601P102: 165 mm stroke, SSI output, 15-pin D-sub connector variant for space-constrained installations.
RHM0500MD601P102: 500 mm stroke, SSI output, 15-pin connector, compatible with Siemens SIMOTION and SINUMERIK.
RHM0165MF111P102: 165 mm stroke, PROFIBUS-DP output, direct fieldbus node, eliminates analog I/O cards.
RHM0500MF111P102: 500 mm stroke, PROFIBUS-DP output, GSD file available, plug-and-play with Siemens S7 systems.
RHM1000MF111P102: 1000 mm stroke, PROFIBUS-DP output, for large-scale hydraulic press and casting machine integration.
RHM0250ME111P102: 250 mm stroke, EtherNet/IP output, native Rockwell/Allen-Bradley integration, CIP-compliant.
RHM0500ME111P102: 500 mm stroke, EtherNet/IP output, real-time position data over standard Ethernet infrastructure.
RHM0165MN111P102: 165 mm stroke, PROFINET output, IRT-capable, for Siemens TIA Portal environments.

Sourcing Hard-to-Find & Obsolete Temposonics RHM Parts

A significant portion of the installed RHM base in global heavy industry consists of units manufactured between 1995 and 2015. Many of these part numbers — particularly early analog-output and Start/Stop variants — have been discontinued by MTS Sensors or carry lead times exceeding 20 weeks through standard distribution channels. DriveKNMS maintains a dedicated inventory of legacy and hard-to-find RHM series sensors, sourced through certified industrial surplus channels and tested to OEM functional specifications before dispatch.

Quality Control for the Temposonics RHM Range

Each RHM series unit processed by DriveKNMS undergoes a structured functional verification protocol specific to magnetostrictive sensor technology. Testing covers: full-stroke position linearity verification using a calibrated reference encoder, output signal integrity check across the complete measurement range (SSI clock/data timing, analog output accuracy at 0%, 50%, and 100% FSO, Start/Stop pulse width measurement), connector and cable assembly inspection for pin continuity and insulation resistance, housing seal integrity check per IP67 rating requirements, and EMC susceptibility screening for units destined for high-interference environments such as arc furnace or VFD-dense installations. Units exhibiting non-linearity exceeding ±0.05% FSO, signal dropout, or connector degradation are quarantined and not dispatched. Test records are retained and available upon request for regulated industries including nuclear, pharmaceutical, and aerospace.