Bently Nevada 172103-01 3500/65 RTD/Isolated Tip TC I/O Module

Product Overview

The Bently Nevada 172103-01 is a 16-channel temperature monitor input/output (I/O) module designed for the 3500/65 machinery protection system rack. It provides physical connection interfaces for resistance temperature detectors (RTDs) and isolated tip thermocouples (TCs). The module features internal terminations, allowing field wiring from temperature sensors to connect directly to the terminal block on the rear of the 3500 rack without requiring external termination blocks.

This I/O module interfaces directly with the 3500/65 monitor module to condition continuously sampled temperature data. It is primarily utilized in critical machinery applications, including steam and gas turbine bearings, large motor stator windings, compressor discharge lines, and industrial pump housing monitoring. The module supports both continuous alarm verification and machinery trip logic integration when combined with the 3500 system relay modules.

Ordering Information

• Part Number: 172103-01

• Manufacturer: Bently Nevada (Baker Hughes)

• Monitor Compatibility: 3500/65 16-Channel Temperature Monitor

• Termination Type: Internal Terminations (Includes 20-pin terminal plug, part number 173005)

• Functional Group: Machinery Protection System Spare Parts

Technical Specifications

Hardware Configuration & Sensor Compatibility

The 172103-01 module accepts a mixed configuration of thermocouples and RTDs within the 3500 Rack Configuration Software. The supported sensor ranges are detailed below:

• Type E TC (Isolated Tip): -100°C to +1000°C (-148°F to +1832°F)

• Type J TC (Isolated Tip): 0°C to +760°C (32°F to +1400°F)

• Type K TC (Isolated Tip): 0°C to +1370°C (32°F to +2498°F)

• Type T TC (Isolated Tip): -160°C to +400°C (-256°F to +752°F)

• 100 Ω Platinum RTD (Pt100, alpha = 0.00385): -200°C to +850°C (-328°F to +1562°F)

• 100 Ω Platinum RTD (Pt100, alpha = 0.00392): -200°C to +850°C (-328°F to +1562°F)

• 120 Ω Nickel RTD (Ni120): -200°C to +700°C (-328°F to +1292°F)

• 10 Ω Copper RTD (Cu10): -80°C to +260°C (-112°F to +500°F)

Engineering & Installation Guide

• Grounding and Shielding: Temperature sensor cable shields must be terminated at a single point. Connect the shield wires to the dedicated chassis ground terminals on the 3500 rack. Do not ground the shield at both the sensor end and the module end to prevent ground loops.

• Thermocouple Constraints: Only isolated tip thermocouples are compatible with the 172103-01. Grounded tip thermocouples must not be used, as they introduce common-mode voltage errors across channels sharing the same input multiplexer circuitry.

• Wiring Separation: Route low-voltage RTD/TC signal wires through dedicated, separate cable trays. Avoid proximity to high-voltage motor power leads, variable frequency drive (VFD) outputs, or switching inductive loads to prevent electromagnetic interference (EMI) injection.

• 4-Wire RTD Modifications: Standard internal termination modules are configured for 3-wire RTD compensation. If 4-wire RTD sensors are deployed, check the specific hardware modification code (such as Modification 179952-01) required for physical multi-wire jumper accommodation.

• Hot Swapping Precautions: While the 3500/65 monitor main card supports online insertion/removal, disconnecting the 172103-01 I/O module while the monitor is live will immediately disrupt sensor loops, triggering channel faults and potential rack-level Danger alarms. Bypass any related voting logic or shutdown interlocks prior to module extraction.

Technical FAQ

• Can I use the 172103-01 module with an external termination block?
  No. The 172103-01 is explicitly designed for internal terminations where field wiring connects directly to the rack backplane plug. For external termination blocks, the 172109-01 external termination I/O module must be ordered instead.

• What happens if a temperature sensor wire breaks or disconnects?
  The 3500/65 monitor automatically executes a transducer limit check. A broken wire triggers an "Open Circuit" or "Not OK" status for that specific channel. The Channel OK LED on the front main card will flash, and the channel's output status is driven out of range to prevent false machine trips.

• Is firmware updating required when replacing an older revision I/O module with a new 172103-01?
  If upgrading or replacing an older configuration, verify that the 3500/65 main monitor card firmware version is compatible. Incompatible firmware may result in configuration mismatches or a continuous "Configuration Error" fault in the rack event log.

• How is Cold Junction Compensation (CJC) managed for thermocouples?
  The 172103-01 features a solid-state temperature sensor integrated directly on the terminal block board assembly. This sensor tracks changes in terminal temperature and applies digital compensation factors inside the 3500/65 monitor processing layer.