I. Complete Model Analysis (330851-A-B-C-D-E-F-G)

330851: 3300 XL 25mm differential expansion / large displacement dedicated probe

05 (A): Probe housing → M30×2 thread, high-temperature extended type (compatible with > 120℃)

000 (B): Threadless length → 0mm (standard)

040 (C): Total length of probe + cable → 4.0m (4 meters)

10 (D): Cable type → High-temperature non-armored (-40℃ to +120℃)

00 (E): Probe end / special option → Standard flat head

05 (G): Certification → Explosion-proof (ATEX/IECEx), Zone 0/1/2 hazardous areas available

II. Core Parameters (Electrical / Mechanical / Environmental)

1. Electrical (matching 25mm system)

Sensitivity: 0.787V/mm (20mV/mil)

Linear range: 0 to 12.7mm (500mil) (differential expansion dedicated)

Frequency response: 0 to 5kHz

Output: -24V DC coaxial signal, double-layer shielding (single-ended grounding)

Adapter: 330850-040-05 (4m, explosion-proof)

Extension cable: 330854-040-24-05 (4m, non-armored, explosion-proof)

2. Mechanical

Thread: M30×2; probe diameter ≈ 25mm; length ≈ 80mm

Cable: 4m high-temperature insulation (FluidLoc), outer diameter ≈ 6mm

Connector: Special waterproof coaxial, IP67

Minimum bending radius: ≥ 50mm

3. Environmental

Temperature: -40℃ to +120℃ (cable), +150℃ (probe end short-term)

Vibration: 10g; resistant to oil, aging, and hydrogen embrittlement

Certification: Explosion-proof (05), available in hazardous areas for oil/gas/chemical industries

III. System Kit (must be the same length + same certification)

✅ Complete 4m explosion-proof non-armored differential expansion system

Probe: 330851-05-000-040-10-00-05 (4m, high-temperature, explosion-proof)

Extension cable: 330854-040-24-05 (4m, non-armored, explosion-proof)

Adapter: 330850-040-05 (4m system, explosion-proof)

Monitoring module: 3500/45M (differential expansion / axial displacement)

IV. Applicable Scenarios

✅ Turbine / generator differential expansion (DE), large shaft axial displacement monitoring

✅ 4m medium distance, high-temperature environment (≤120℃) + explosion-proof hazardous area

✅ Hydrogen-cooled generator, sealing unit, oil/gas chemical equipment

✅ Conventional factory buildings, no strong mechanical compaction risk (non-armored)

V. Key Models of the Same Series (4m, explosion-proof) Table

Model Shell 电缆 Armor Approval Applicable Scenarios

330851-05-000-040-10-00-05 High-temperature M30 4m No Explosion-proof High temperature + Hazard zone + General protection

330851-02-000-040-10-00-05 Standard M30 4m No Explosion-proof Normal temperature + Hazard zone + General protection

330851-05-000-040-50-00-05 High-temperature M30 4m Yes Explosion-proof High temperature + Hazard zone + Strong protection (Armor)

Six, Installation and Matching Key Points

Length must match strictly： The 4m probe must be paired with 4m extension cable + 4m preamplifier； do not mix 8m/12m.

Explosion-proof zone specification： The joint sealing is compliant； the shielding layer is only grounded at one end on the preamplifier side.

High-temperature note： The probe end can withstand 150℃ for a short time， and the cable should not exceed 120℃ for a long time.

Non-armor limitation： Avoid crushing， sharp bending， rat bites； the bending radius should be ≥ 50mm.

Seven， Common Confusion Clarification

❌ Not 8mm/50mm probe： 330851 is exclusive for 25mm differential expansion system， and cannot be exchanged with 330930 (8mm) or 330876 (50mm).

❌ 05≠02： 05 is the high-temperature extended shell， suitable for higher temperature working conditions； 02 is the standard shell.

✅ Differential expansion specific： Linear range 12.7mm， used for rotor - stator relative expansion， not for small gap vibration measurement.