Bently Nevada 3500/61 Temperature Monitor with Recorder Outputs
Overview
The Bently Nevada 3500/61 is the recorder-output version of the six-channel temperature monitor for the Bently Nevada 3500 machinery protection system. Like its sister module it accepts resistance temperature detector (RTD) and thermocouple (TC) inputs, conditions them, and compares each reading with user-programmable alarm setpoints. What sets the Bently Nevada 3500/61 apart is that every one of its six channels also drives its own +4 to +20 mA recorder output proportional to the monitor full scale, so bearing, winding and gas temperatures can be passed to a DCS, chart recorder or PLC without a second set of transmitters.
Seven Star LLC supplies the Bently Nevada 3500/61, its I/O modules and its recorder termination hardware on request to plants in the Sultanate of Oman and the GCC, with engineering support in Muscat. The manufacturer datasheet shared by the 3500/60 and the Bently Nevada 3500/61 (141540 Rev. L) is attached here, and our engineers can confirm which I/O module, termination style and approval code suit a given rack before ordering.
Measurement Principle
Each channel of the Bently Nevada 3500/61 is set in the 3500 Rack Configuration Software for RTD or TC measurement, and the full-scale range is also set there, so no field calibration is required. For RTDs the module supplies an excitation current of 925 ±15 µA per transducer at 25 °C, using a single supply for 4-wire sensors and two supplies for 3-wire sensors, and reads the resulting voltage through a 10 MΩ input on each lead. For thermocouples a cold junction compensation sensor, accurate to ±1 °C at 25 °C, corrects for the terminal temperature. Resolution is 1 °C or 1 °F, and accuracy at 25 °C ranges from ±1 °C to ±3 °C depending on the I/O module and rack type.
The measured temperature is compared with Alert and Danger setpoints that can be placed anywhere from 0 to 100% of full scale, with both under and over alarms and an alarm accuracy within 0.13% of the desired value. Alert delays run from 1 to 60 seconds in 1-second steps and Danger delays from 1 to 60 seconds in 0.5-second steps. In parallel, the Bently Nevada 3500/61 converts each channel value into its recorder current with a resolution of 0.3662 µA per bit, ±0.15% error at room temperature and ±0.4% over the temperature range, and a short circuit on a recorder output does not affect monitor operation.
Engineering Design of the Bently Nevada 3500/61
The Bently Nevada 3500/61 fills one full-height front slot and one full-height rear slot. The front module is 241.3 × 24.4 × 241.8 mm and weighs 0.91 kg, with OK, TX/RX and Bypass LEDs on its face; nominal power consumption is 9 W, compared with 7 W for the 3500/60, reflecting the six recorder drivers. Recorder outputs work into a 0 to 600 Ω load with 0 to +12 Vdc voltage compliance.
Three families of rear I/O are offered. The RTD/TC non-isolated module can be configured for all TC, all RTD or a mixture of both. The TC isolated module provides 500 Vdc system isolation and 250 Vdc channel-to-channel isolation, which guards long thermocouple runs against external interference and ground faults. The internal barrier module adds intrinsically safe zener barriers for sensors in hazardous areas, and it is 163.1 mm deep instead of 99.1 mm. When external terminations are chosen, the 3500/61 uses separate termination blocks for the transducer signals and for the recorder outputs, each with its own cable.
Key Features
The main functions of the Bently Nevada 3500/61 described in the manufacturer datasheet are:
- Six channels accepting RTD or thermocouple inputs, configurable individually in the 3500 software.
- An individual +4 to +20 mA recorder output for each channel, proportional to monitor full scale.
- Thermocouple types E, J, K and T, plus 100 Ω platinum, 120 Ω nickel and 10 Ω copper RTDs in 3-wire or 4-wire form.
- TC isolated I/O with 250 Vdc channel-to-channel and 500 Vdc system isolation.
- Internal barrier I/O for intrinsically safe connection of field sensors.
- Alert and Danger setpoints with both under and over alarms, adjustable from 0 to 100% of full scale.
- SIL 2 functional safety rating and design to meet IEC 62443 cyber security requirements.
- DNV GL and ABS marine classification, with cNRTLus, ATEX and IECEx hazardous area options.
Industrial Applications
Temperature is often the first sign of trouble on fluid-film bearings, thrust pads and motor windings, and many operators want those values both in the protection rack and in the control room. The Bently Nevada 3500/61 is chosen when the DCS or a local panel needs a hard-wired 4 to 20 mA signal for each sensor in addition to the rack alarms; where only alarming and digital data are required, the Bently Nevada 3500/60 Temperature Monitor without recorder outputs is the usual choice. Typical machines in Oman include gas turbine generator sets, export gas compressors, seawater lift and injection pumps, and large induction motors in desalination plants.
In a typical machine train the Bently Nevada 3500/61 sits alongside vibration modules such as the 3500/40M Proximitor Monitor, and its alarms can be routed to relay cards like the Bently Nevada 3500/32M 4-Channel Relay Module for trip voting. For brownfield work in Sohar, Duqm and Salalah, Seven Star LLC helps maintenance teams in Oman and the GCC identify which part number is fitted, whether the recorder termination block is terminal-strip or Euro-style, and which spare I/O module to hold.
Ordering Information
The Bently Nevada 3500/61 is ordered as 3500/61-AA-BB. The option codes below are taken from the manufacturer datasheet.
| Option | Code | Description |
|---|---|---|
| A: I/O Module Type | 01 | RTD/TC Non-isolated I/O Module Internal Terminations |
| A: I/O Module Type | 02 | RTD/TC Non-isolated I/O Module External Terminations |
| A: I/O Module Type | 03 | TC Isolated I/O Module Internal Terminations |
| A: I/O Module Type | 04 | TC Isolated I/O Module External Terminations |
| A: I/O Module Type | 05 | RTD/TC Non-isolated I/O Module with Internal Barriers |
| B: Agency Approval | 00 | None |
| B: Agency Approval | 01 | CSA/NRTL/C (Class 1, Div 2) |
| B: Agency Approval | 02 | ATEX/IECEx/CSA (Class 1, Zone 2) |
Spares and recorder hardware specific to the Bently Nevada 3500/61:
| Part Number | Description |
|---|---|
| 163179-02 | 3500/61 Temperature Monitor (with recorders) |
| 133819-02 | 3500/61 RTD/TC Non-Isolated I/O Module Internal Terminations |
| 133827-02 | 3500/61 RTD/TC Non-Isolated I/O Module External Terminations |
| 133835-02 | 3500/61 TC Isolated I/O Module Internal Terminations |
| 133843-02 | 3500/61 TC Isolated I/O Module External Terminations |
| 136711-02 | 3500/61 RTD/TC I/O Module with Internal Barriers and Internal Terminations (Not-Isolated) |
| 133892-01 | 3500/61 Recorder Output External Termination Block (Terminal Strip connectors) |
| 133900-01 | 3500/61 Recorder Output External Termination Block (Euro Style connectors) |
| 134543-AAAA-BB | 3500/61 Recorder Output to External Termination (ET) Block Cable; AAAA length 0005, 0007, 0010, 0025, 0050 or 0100 feet; BB 01 not assembled, 02 assembled |
| 134544-AAAA-BB | 3500/60 and 3500/61 Transducer (XDCR) Signal to External Termination (ET) Block Cable |
| 133908-01 / 133916-01 | RTD/TC Non-Isolated External Termination Block (Terminal Strip / Euro Style connectors) |
| 133924-01 / 133932-01 | TC Isolated External Termination Block (Terminal Strip / Euro Style connectors) |
| 00580442, 00580443, 00502133, 00580444 | Connector Headers, Internal Termination (9-position green, 12-position green, 12-position blue, 15-position green) |
| 134542 | 3500/60 and 3500/61 User Guide |
Technical Specifications
Key Bently Nevada 3500/61 data from datasheet 141540 Rev. L:
| Parameter | Specification |
|---|---|
| Model | Bently Nevada 3500/61 Temperature Monitor (with recorder outputs) |
| Inputs | 1 to 6 RTD or TC transducer signals; 10 MΩ input impedance per lead |
| Thermocouple ranges | Type E −100 to +1000 °C; Type J −18 to +760 °C; Type K −18 to +1370 °C; Type T −160 to +400 °C |
| RTD ranges | 100 Ω Pt (0.00385) −200 to +850 °C; 100 Ω Pt (0.00392) −200 to +700 °C; 120 Ω Ni −80 to +260 °C; 10 Ω Cu −100 to +260 °C |
| RTD current source | 925 ±15 µA at 25 °C per transducer |
| Recorder outputs | +4 to +20 mA per channel, proportional to full scale; 0 to +12 Vdc compliance; 0 to 600 Ω load |
| Recorder resolution | 0.3662 µA per bit; ±0.15% at room temperature, ±0.4% over temperature range |
| Isolation (TC isolated I/O) | 500 Vdc system; 250 Vdc channel to channel |
| Resolution / accuracy | 1 °C or 1 °F; ±1 °C to ±3 °C at 25 °C depending on I/O and rack type |
| Alarms | Alert and Danger, under and over, 0–100% of full scale; Alert delay 1–60 s (1 s steps), Danger delay 1–60 s (0.5 s steps) |
| Power consumption | 9 W nominal |
| Operating temperature | −30 to +65 °C with internal/external termination I/O; 0 to +65 °C with internal barrier I/O |
| Storage temperature | −40 to +85 °C |
| Monitor dimensions / weight | 241.3 × 24.4 × 241.8 mm; 0.91 kg |
| I/O module dimensions / weight | 241.3 × 24.4 × 99.1 mm, 0.45 kg; internal barrier 163.1 mm deep, 0.46 kg |
| Approvals | FCC Part 15; EMC 2014/30/EU; LVD 2014/35/EU; RoHS; DNV GL; ABS; SIL 2; CSA/NRTL/C Class I Div 2 / Zone 2; ATEX/IECEx II 3 G or II 3(1) G with barriers |
How to Order
To request a quotation for the Bently Nevada 3500/61, send Seven Star LLC the full 3500/61-AA-BB code or tell us the sensor types, whether thermocouple isolation or intrinsic safety barriers are needed, and how the recorder outputs will be terminated. Our team in Muscat will confirm stock, lead time and any matching termination blocks or cables, and the datasheet is available from the documents tab on this page. We supply the Bently Nevada 3500/61 to customers in Oman and the GCC.
- Datasheet Bently Nevada 3500/60 and 3500/61 Temperature Modules Datasheet (141540 Rev. L) Download
Bently Nevada 3500 modules and transducers
The listed 3500 modules include the 3500/20 Rack Interface Module, the 3500/50M Tachometer, the 3500/61 Temperature and 3500/62 Process Variable monitors, the 3500/64M Dynamic Pressure monitor, the 3500/44M for aeroderivative gas turbines and the 3500/46M Hydro monitor. Reciprocating compressor monitoring is covered by the 3500/70M, 3500/72M and 3500/77M. The 3500/92 Communication Gateway and 3500/94M display link the rack to the control system. Transducers include the 3300 XL proximity probe system, the 330400 accelerometer and the 190501 Velomitor CT velocity transducer. The manufacturer's newer platform, Orbit 60, is offered as the modernization path for 3500 racks, and System 1 software handles diagnostics.Where Bently Nevada vibration monitoring is used
Steam and gas turbines, generators, centrifugal and reciprocating compressors, large pumps, hydro units and cooling tower fans in oil and gas, power generation, petrochemical and mining plants are the usual machines. Measurements include radial vibration, thrust position, speed, phase, differential expansion, bearing temperature, rod position and cylinder pressure.Ordering Bently Nevada parts: what we need
Send the complete part number with every option field, for example 330103-00-05-10-01-00 for a probe or the 3500 module number with its option dashes, plus the matching I/O module number. For probe systems state probe series, system length and the hazardous area approval. A photo of the label avoids transcription errors, and for rack modules the firmware revision is useful.Browse Bently Nevada products by category: Vibration.
Reviews
There are no reviews yet.