| Probe Diameter | 11 mm（330703） | 8 mm（330101） | The 11 mm probe has a larger physical size, which is the physical basis for all its performance differences. |
| Linear Range | 4.0 mm (160 mils) | 2.0 mm (80 mils) | Core difference! The 11 mm probe's linear range is twice that of the 8 mm. Ideal for large displacement scenarios like turbine differential expansion. |
| Extended DSL Range | Up to 5.0 mm (200 mils) | Not Applicable | Provides an additional safety margin by allowing measurement in a wider range while maintaining acceptable accuracy. |
| Scale Factor (ISF) | 3.94 V/mm (100 mV/mil) | 7.87 V/mm (200 mV/mil) | Sensitivity difference! The 8 mm probe has higher sensitivity (more voltage change per unit displacement). The 11 mm trades sensitivity for doubled range. |
| Recommended Gap | 2.5 mm (100 mils) | 1.27 mm (50 mils) | The 11 mm probe requires a larger initial installation gap to utilize the center of its linear range. |
| Frequency Response | 0 - 8 kHz (+0, -3 dB) | 0 - 10 kHz (+0, -3 dB) | The 8 mm probe has superior high-frequency response, capable of capturing higher frequency vibrations, making it more suitable for detailed vibration analysis. |
| Min. Target Size (Flat) | 30.5 mm (1.2 in) | 15.2 mm (0.6 in) | The 11 mm probe requires a larger target area to ensure measurement accuracy and linearity, otherwise edge effects can influence readings. |
| Recommended Min. Shaft Dia. | 152 mm (6.0 in) | 76.2 mm (3.0 in) | For radial vibration measurement, the 11 mm probe requires a larger shaft diameter to minimize measurement errors and cross-talk due to curvature. |
| Cross-Talk Requirement | Axial: ≥64 mm (2.5 in) | Axial: ≥40 mm (1.6 in) | To prevent signal interference (cross-talk) between two probes, the 11 mm requires a larger minimum separation between probe tips. |
| Mechanical Interface | ½-20 UNF, 5/8-18 UNF, M14x1.5, M16x1.5 | 3/8-24 UNF, M10x1 | The 11 mm probe uses larger, more robust mounting threads, accommodating its larger size and potentially harsher mechanical environments. |
| Primary Application | Axial Pos., Differential Expansion, Large Displacement, Low-Freq. Monitoring | Radial Vibration, Keyphasor, General Position Monitoring | Fundamental application difference. The 11 mm specializes in large displacement, low frequency; the 8 mm excels in general vibration, high frequency. |
