Bentley 3300/35 Six-Channel Temperature Monitoring Module Detailed Product Description

I. Product Overview

The Bentley 3300/35 is a six-channel high-precision temperature monitoring module within the 3300 series TSI (Turbo Generator Instrumentation) system of Baker Hughes (formerly GE Bentley Nevada). It is specifically designed for online monitoring and protection of critical parts of large rotating machinery (such as steam turbines, gas turbines, generators, compressors, fans, pump sets, etc.) in industries such as thermal power, nuclear power, petrochemicals, and metallurgy. The module is installed in a 19-inch standard rack and supports hot-swapping. It can be mixed with other monitoring modules of the 3300 series and shares the backplane - 24V DC power supply and system bus; it is compatible with RTD (platinum resistance) and thermocouple (optional) inputs, covering a wide temperature range of -200°C to +1800°C, and features six independent temperature measurements, programmable dual-level alarms, optional relays / analog outputs, complete self-diagnosis and system integration capabilities, in accordance with API 670 standards. It is the core equipment for temperature status monitoring, fault warning and protection of rotating machinery.

II. Model Coding Rules (3300/35- AA- BB- CC- DD- EE- FF)

3300: Bentley 3300 modular TSI system, unified rack, centralized power supply, hot-swappable architecture.

35: Function code, representing the six-channel temperature monitoring module, independently monitoring 6 temperature signals.

AA: Range code, defining the measurement range, such as 01 corresponds to -40°C to +125°C, 02 corresponds to 0°C to +600°C, 13 corresponds to wide temperature / thermocouple range.

BB: Sensor type code, 01 is suitable for Pt100 RTD (three-wire system), 02/03 can be suitable for thermocouples (K/S/T type) or other RTD (Pt1000/Cu50).

CC: Relay configuration code, 00 no relay, 01 single-channel relay, 02 dual-channel SPDT sealed relay (warning + danger).

DD: Analog output configuration code, 00 no analog output, 01 each channel 4–20mA, 02 common 4–20mA output.

EE: Certification level code, 00 general industrial grade, 02 explosion-proof / ATEX Zone 2 certification, SIL2/3 functional safety certification.

III. Core Functions

1. Six-channel multi-type sensor compatible temperature measurement

Independent 6 channels of input, supporting Pt100/Pt1000/Cu50 RTD (three-wire system, IEC 751 standard) or K/S/T type thermocouples (optional), covering an extremely wide temperature range of **-200°C to +1800°C**, suitable for low-temperature to high-temperature measurement points in different parts such as bearings, windings, lubricating oil, sealing cavities, media, and shells. Using high-precision constant current source excitation (RTD) or cold junction compensation (thermocouple) technology, measurement accuracy ≤ ±0.1°C (25°C reference point, RTD), resolution 0.1°C, response time ≤ 3 seconds (90% stable reading), capable of accurately capturing small temperature changes. Real-time monitoring of sensor circuit status, warning of broken wires, short circuits, wiring errors, cable damage, etc., suitable for complex working conditions with strong electromagnetic interference, high vibration, humid dust, etc.

2. Programmable dual-level alarm and multi-output configuration

Each channel independently configures **alert (ALERT), danger (DANGER)** two-level alarm thresholds, supports on-site / remote configuration, alarm delay 0–10 seconds adjustable, filtering instantaneous fluctuations to prevent false alarms. Relay output options available: dual-channel sealed SPDT relay (contacts 250V AC/5A, 30V DC/5A), moisture-proof, dust-proof, vibration-resistant, capable of driving sound and light alarms, DCS/PLC interlocks or shutdown protection. Analog output options available: each channel independently 4–20mA or common 4–20mA, suitable for remote signal transmission to third-party systems; no output version focuses solely on pure data acquisition, simplifying the circuit and enhancing stability.

3. Local display and convenient configuration

The front panel is equipped with an LCD digital display window and multiple status LED (OK, ALERT, DANGER, BYPASS), displaying real-time 6-channel temperature values, loop resistance, alarm thresholds, and fault codes. The operating status is clearly visible. Supports button-based local configuration, allowing for range calibration, sensor type matching, loop resistance calibration, alarm threshold/delay settings, output configuration, diagnostic parameter adjustments, etc., without the need for an upper computer, enabling efficient and convenient debugging and reducing maintenance difficulty.

4. Comprehensive self-diagnosis and fault identification

24-hour continuous monitoring of module hardware, sensor circuits, power supply status, and signal integrity, accurately identifying sensor breakage/short circuit, wiring errors, power fluctuations, circuit faults, over-range issues. Distinguishing between true temperature anomalies and sensor/circuit faults, with clear LED indications and fault codes on the panel, facilitating quick troubleshooting and reducing unplanned downtime risks caused by monitoring failure.

5. System integration and strong anti-interference capability

Metal shielding enclosure, multiple electrical isolation between input/output/power supply, insulation strength ≥ 2500V AC, suitable for fire power, nuclear power, petrochemical, etc., with strong electromagnetic interference and high vibration industrial environments. Compatible with 3300 series system bus (type A), can be connected to the Bently System 1 platform, enabling remote configuration, real-time data transmission, historical trend query, fault warning analysis, data recording and report generation. Supports interfacing with DCS, PLC, SCADA and other third-party systems through bus protocol or 4–20mA analog signal, integrating into the enterprise equipment management system to ensure stable data transmission.

Four. Detailed technical parameters

Measurement parameters

Monitoring channels: 6 independent temperature measurements (RTD / thermocouple options available)

Sensor types: Pt100/Pt1000/Cu50 RTD (three-wire system), K/S/T type thermocouples (optional)

Measurement range: RTD: -40°C ~ +600°C; thermocouple: -200°C ~ +1800°C

Measurement accuracy: RTD: ≤ ±0.1°C (25°C reference point); thermocouple: ≤ ±0.5°C

Resolution: 0.1°C

Excitation current: 1mA constant current source per channel for RTD; cold end automatic compensation for thermocouples

Response time: ≤ 3 seconds (90% stable reading)

Input impedance: ≥ 10MΩ (per channel)

Electrical parameters

Operating power supply: -24V DC (±10%), backplane power supply; supports short circuit switching - 18V DC

Power consumption: typical 3.0W, maximum ≤ 5.0W

Relay output: 0–2 SPDT (ALERT + DANGER), sealed type, 250V AC/5A, 30V DC/5A

Analog output: 0–6 4–20mA (load ≤ 500Ω) or common 4–20mA

Isolation strength: input/power supply ≥ 2500V AC; input/output ≥ 1500V AC

Sensor power supply: module internal excitation, no external power supply required

Environmental and mechanical parameters

Operating temperature: 0°C ~ +65°C (standard); -30°C ~ +70°C (wide temperature option) Storage temperature: -40℃ to +85℃

Relative humidity: 5%–95% (no condensation)

Vibration tolerance: Compliant with IEC 60068-2 standards, resistant to vibration and shock

Installation method: 19-inch standard rack slot, supports hot swapping

Dimensions: 203mm (height) × 330mm (depth) × 51mm (width)

Weight: Approximately 1.4kg

Protection level: IP20 (inside the control cabinet); IP62 (optional sealing)

Certifications and compliance

Industry standards: Compliant with API 670 Rotating Machinery Monitoring and Protection Standards

Electromagnetic compatibility: CE certification, compliant with EN 61000-6-2/4

Safety certification: UL certification, SIL2/3 functional safety certification (optional)

Explosion-proof certification: ATEX/IECEx Zone 2 (optional, code - 02)

Environmental compliance: RoHS Directive compliance

V, Typical application scenarios

Power industry (thermal power / nuclear power turbine / generator): Multi-point monitoring of turbine bearing temperature, generator winding temperature, lubricating oil temperature, sealing oil temperature, stator core temperature, covering the low-temperature to high-temperature range, protection during startup, operation, and shutdown, triggering alarms or interlock shutdown for over-temperature, ensuring safe and stable operation of the unit.

Petrochemical industry (large compressors / pump sets / heating furnaces): Synchronous monitoring of compressor bearing temperature, pump set winding temperature, heating furnace tube wall temperature, medium temperature, outdoor equipment shell temperature, suitable for humid, dusty, high-temperature, outdoor and other harsh environments, preventing overheating from causing equipment failure and production interruption, ensuring continuous industrial production.

Metallurgical industry (large motors / fans / cooling equipment / rolling mills): Batch monitoring of motor winding temperature, fan bearing temperature, cooling medium temperature, key components of rolling mills, dual-level alarm linkage with equipment interlock, timely warning of abnormalities, reducing unplanned downtime risks, ensuring stable and efficient metallurgical processes.

Other industrial fields (large gas turbines / air separation equipment / pump stations): Suitable for temperature monitoring requirements of various large rotating machinery and key equipment, providing high-precision data acquisition, reliable alarm protection and system integration capabilities, supporting equipment condition assessment, predictive maintenance and safe production.

VI. Installation and commissioning specifications

Installation requirements

Rack installation: Push in smoothly into the 3300 series rack empty slot, ensure that the rear connectors are fully engaged, tighten the panel screws, reserve ventilation space, avoid heat accumulation affecting heat dissipation.

Sensor wiring: RTD uses three-wire system (red / white / black), the positive and negative poles of the thermocouple are clearly distinguished; use dedicated shielded cables, single-ended grounding of the shielding layer (on the control cabinet side), avoid circulating interference; wiring is firm, away from strong electromagnetic sources.

Output wiring: Relay contacts distinguish common terminal / normally open / normally closed, connect to alarm / interlock circuits; positive and negative poles of the analog output are correct, the load is ≤ 500Ω; for harsh environment terminals, take measures for moisture and dust protection.

Sensor installation: The probe is tightly attached to the measured surface, fixed with thermal conductive silicone + high-temperature-resistant fixture, the cable is firmly fixed to prevent vibration wear, for humid environments, the probe is protected against water.

Commissioning steps

Power-on self-check: After power-on, it automatically self-checks, the OK light is constantly on as normal, the fault light is on to check the wiring, sensors or hardware.

Sensor calibration: Enter the calibration mode, select the sensor type, calibrate the RTD circuit resistance or thermal couple cold junction compensation, ensure accuracy.

Alarm and output settings: Set the warning / danger threshold according to the equipment standard, set the delay; configure the relay action logic, mapping relationship of analog output, save parameters. Signal verification: During equipment operation, observe that the 6 channels of temperature are stable without any fluctuations, there are no fault prompts in the circuit, and the alarm/output functions are normal before putting it into operation.

VII. Maintenance and Fault Troubleshooting

Daily maintenance

Regular inspection: Daily observation of panel temperature and LED status, confirmation of no alarm faults; check that terminal connections are not loose, oxidized, or damp, and the rack ventilation is good.

Annual calibration: Use standard sensors to calibrate temperature accuracy, verify the action values of relays, and the accuracy of analog outputs, to ensure reliable functions.

Cleaning and protection: Regularly clean dust with a dry soft cloth to avoid heat accumulation; strictly prohibit liquids, metal debris from entering the interior; regularly check the sealing performance in harsh environments.

Common fault troubleshooting

OK light goes out (module failure): Check the backplane - 24V DC power supply, reinsert and re-execute the module, if abnormal, replace the module.

Abnormal temperature display (fluctuation / drift): Check for loose / incorrect wiring of the sensor, breakage / moisture of the wire, and damaged cables, rewire or replace the sensor; investigate strong electromagnetic interference, and check if the environmental temperature is out of range.

No temperature display: Check for sensor damage, incorrect wiring, or broken cables, and replace the faulty component.

Alarm mis-triggering: Re-calibrate the threshold / delay, check for abnormal circuit resistance, optimize wiring shielding and moisture-proof measures.

Analog output abnormality: Check for overload of the load, incorrect wiring, or incorrect output configuration, and investigate and adjust.

VIII. Usage Precautions

Non-explosion-proof type (default) must not be used in flammable and explosive hazardous areas; explosion-proof type must be installed strictly according to the certified area.

It must be paired with corresponding sensors (RTD three-wire system / thermocouple) and dedicated shielded cables; do not mix sensor types; otherwise, errors or equipment damage will occur.

Use strictly within the range; select the corresponding range module for scenarios beyond the range.

Do not disassemble the module, modify the circuit, or replace non-original accessories privately; violation will result in the invalidation of warranty and trigger safety hazards.

Before wiring and maintenance, cut off the main power supply of the rack to prevent short circuits and electric shock; do not plug or unplug the module while it is powered on.

When the equipment is in a long-term shutdown state, remove the module and store it in a dry and cool environment to avoid the influence of moisture and dust on performance.