Bently Nevada 3300 XL 8 mm Probe Model Identification Guide
Read Bently Nevada 3300 XL 8 mm proximity probe catalog numbers: base P/N, length options, armor/FluidLoc, and probe–extension–Proximitor matching for API 67...
The Bently Nevada 3300 XL 8 mm eddy-current proximity transducer system is the workhorse sensor stack for large rotating machinery. It is designed to meet API 670 (4th edition) expectations and remains the default choice for shaft relative vibration and thrust-position measurements on turbomachinery trains.
3300 XL 8 mm system overview used for shaft vibration and axial position.
The transducer outputs a negative voltage proportional to the gap between the probe tip and a conductive target. The same channel can report static gap (displacement/position) and dynamic motion (vibration). Typical duties include radial shaft vibration and axial thrust position.
Why the 8 mm probe dominates field installs
| Feature | What it means on the machine |
|---|---|
| Full interchangeability | Probe, extension cable, and Proximitor can be mixed without matched sets or bench calibration |
| Backward compatibility | Interchanges with non-XL 5 mm and 8 mm components for staged upgrades |
| RFI/EMI immunity | Improved radiated immunity; CE compliance without special shielded conduit in typical layouts |
| Mounting flexibility | DIN-rail or conventional panel Proximitor mounting |
| Mechanical toughness | Thicker coil encapsulation and a larger body than 5 mm probes reduce field damage |
Where installation space allows, prefer an 8 mm probe over a 5 mm unit to reduce mechanical damage risk during install and maintenance.
How to read the complete model string
A full 3300 XL 8 mm probe catalog number is a base part number plus five option groups. Every digit group maps to a hardware choice.
Model-number breakdown for imperial and metric 3300 XL 8 mm probes.
Imperial example: 330101-00-08-05-02-00
| Segment | Meaning | Reading |
|---|---|---|
| 330101 | Base model | 3300 XL 8 mm probe, 3/8-24 UNF, unarmored |
| -00 | Unthreaded length | 0.0 in (exposed tip length not used for mounting) |
| -08 | Case length | 0.8 in threaded case (minimum) |
| -05 | Overall length | 5.0 m integral cable |
| -02 | Connector / cable | Standard cable with miniature coaxial ClickLoc™ connector |
| -00 | Agency approvals | No special agency approval required |
Metric example: 330103-00-02-10-02-00
| Segment | Meaning | Reading |
|---|---|---|
| 330103 | Base model | 3300 XL 8 mm probe, M10×1, unarmored |
| -00 | Unthreaded length (A) | 0 mm |
| -02 | Case length (B) | 20 mm |
| -10 | Overall length (C) | 1.0 m |
| -02 | Connector / cable (D) | 00 = no connector; 02 = miniature coaxial ClickLoc™ |
| -00 | Approvals (E) | 00 = none; 05 = multiple approvals; CN = China national |
Length matching across probe, extension, and Proximitor
System electrical length must be coherent: probe cable length + extension cable length must equal the Proximitor’s rated system length. A 5 m probe string only works with a 5 m Proximitor; a 9 m string only with a 9 m Proximitor. Mismatched lengths will not calibrate or operate correctly.
| Probe option (C) | Probe length | Extension | Proximitor system length |
|---|---|---|---|
| 05 | 0.5 m | as required | uncommon; pair with a suitable extension |
| 10 | 1.0 m | 040 (4.0 m) | 5.0 m → 50 |
| 15 | 1.5 m | 035 (3.5 m) | 5.0 m → 50 |
| 20 | 2.0 m | 030 (3.0 m) | 5.0 m → 50 |
| 50 | 5.0 m | none | 5.0 m → 50 |
| 90 | 9.0 m | none | 9.0 m → 90 |
Length-matching chart for 3300 XL probe, extension cable, and Proximitor.
8 mm versus 11 mm selection
| Item | 3300 XL 8 mm | 3300 XL 11 mm |
|---|---|---|
| Linear range | 2.0 mm (80 mils) | 4.0 mm (160 mils) |
| Sensitivity | 7.87 V/mm (200 mV/mil) | 3.94 V/mm (100 mV/mil) |
| Minimum shaft diameter | ≥ 76 mm (3.0 in) | ≥ 152 mm (6.0 in) |
| Typical use | Radial vibration, position, Keyphasor, speed | Large axial travel, differential expansion, reciprocating rod drop |
Use 8 mm for most vibration and position channels. Move to 11 mm when axial travel, differential expansion, or reciprocating rod-drop monitoring needs the wider linear range.
Base probe families
| Base P/N | Thread | Mount | Typical use |
|---|---|---|---|
| 330101 / 330102 | 3/8-24 UNF | Standard | Most installs |
| 330103 / 330104 | M10×1 | Standard | Metric thread requirements |
| 330105 | 3/8-24 UNF | Reverse mount | Limited access; install from inside out |
| 330106 | M10×1 | Reverse mount | Metric reverse mount |
| 330140 / 330141 | Smooth case | Bracket | No tapped hole available |
| 330191–330198 | Various | ETR | Cable ambient > 177 °C |
Armor, FluidLoc, and connector protectors
Armor adds a stainless braid over the probe or extension cable. Unarmored options (00/02) stay lighter and more flexible for benign runs. Armored bases (suffix families such as 02/04/08) raise tensile strength for wet, abrasive, or frequently handled routes.
FluidLoc® cable options (10/11/12) block oil wicking into the machine along the cable core. Connector protectors (01 or 11) are strongly recommended on every install to keep ClickLoc™ gold-plated contacts dry and clean.
Common 3300 XL 8 mm base models by thread, armor, and temperature rating.
Quick base-model reference
| Base | Thread | Armor | Temperature |
|---|---|---|---|
| 330101 | 3/8-24 UNF | Unarmored | Standard |
| 330102 | 3/8-24 UNF | Armored | Standard |
| 330103 | M10×1 | Unarmored | Standard |
| 330105 | 3/8-24 UNF | No armor option | Standard |
| 330140 | Smooth | Unarmored | Standard |
| 330191 | 3/8-24 UNF | Unarmored | ETR (−51 to 260 °C cable) |
Extension cables (330130) and Proximitors (330180)
Common 330130 lengths: 030, 035, 040, 045, 070, 075, 080, 085 (meters × 10). Rule: probe length + extension = 5 m or 9 m.
Example: 330130-085-00-05 — 8.5 m total; connector/cable option 00–03 and FluidLoc 10–13; approvals 00 / 05 / CN.
330180 Proximitor system-length digits: 5 = 5.0 m, 9 = 9.0 m. Mount digit: 0 panel, 1 DIN rail, 2 no hardware — for example 50/51/52 and 90/91/92.
ETR (extended temperature range)
| Component | Standard | ETR |
|---|---|---|
| Probe tip | −51 to +177 °C | −51 to +177 °C |
| Probe cable / connector | −51 to +177 °C | −51 to +260 °C |
| Extension cable | −51 to +177 °C | −51 to +260 °C |
If any ETR component is in the string, the whole loop inherits ETR accuracy (ISF ±18%, DSL ±0.152 mm). Do not mix ETR and standard parts and still claim standard-system accuracy.
Selection checklist
- Match probe + extension to the Proximitor system length (5 m or 9 m).
- Prefer 8 mm over 5 mm when space allows.
- Recheck sensitivity if shaft diameter is below 76 mm.
- Treat any ETR part as an ETR system for accuracy.
- Factory calibration assumes AISI 4140; other target materials need recalibration.
- Specify connector protectors on every ClickLoc joint.
Keep spare probe, extension, and Proximitor sets under Bently Nevada condition-monitoring stock, and align related rack I/O with PLC and PAC systems so length-matched replacements are available during an outage.
Compiled from Bently Nevada 3300 XL 8 mm product documentation and related public technical material. Final selection must follow the latest official datasheet and the project’s API 670 / site standards.
About the Author
James Keller | Condition Monitoring Specialist – Bently Nevada Systems
James Keller works on proximity-probe and 3500/3300 monitoring trainouts for turbomachinery fleets. His day-to-day focus is probe–extension–proximitor length matching, API 670 sensor selection, and field calibration against AISI 4140 and alternate target materials.
