1756-OF4 Output Wrong? Check Mode, RTB, and Scaling First
A field-first diagnostic sequence for 1756-OF4 analog output problems: channel mode, removable terminal block, scaling, and controlled electrical checks.
Manufacturer: Bently Nevada
Product No.: 330850-51-CN
Country of origin:United States
Product Type: 3300 XL 25 mm Proximitor Sensor
Barcode: 8537101190
Payment: T/T, Western Union
Weight: 350g
Dimensions: 70 mm x 120 mm x 120 mm (H x W x D)
Shipping port: Xiamen
Warranty: 12 months
330850-51-CN specifies this 3300 XL 25 mm Proximitor Sensor configuration, featuring a 5.0-metre (16.4-foot) system length, a DIN-rail mount design (Option 51), and the -CN China hazardous area approval package (NEPSI and CCC approvals).
This sensor accepts input from a 3300 XL 25 mm proximity probe and extension cable to complete a 5.0-metre transducer system. The system yields an average scale factor of 0.787 V/mm (20 mV/mil) over a 12.7 mm (500 mils) linear range, which is used for measuring differential expansion on mid-size to large steam turbine generators or shaft vibration and axial position on industrial machinery.
| Option | Option Code on This SKU | Description |
|---|---|---|
| Orderable Part Number | 330850-51-CN | 3300 XL 25 mm Proximitor Sensor |
| Total Length and Mounting Option | 51 | 5.0 metres (16.4 feet) system length, DIN mount |
| Agency Approval Option | CN | China hazardous area approval package (NEPSI + CCC + applicable markings) |
| Parameter | Specification |
|---|---|
| Manufacturer | Bently Nevada (Baker Hughes) |
| Model Number | 330850-51-CN |
| System Compatibility | 3300 XL 25 mm Proximity Transducer System |
| System Length | 5.0 metres (16.4 feet) |
| Mounting Type | DIN rail mount |
| Power Requirements | -17.5 Vdc to -26 Vdc (no barriers), -23 Vdc to -26 Vdc (with barriers); 12 mA maximum current consumption |
| Linear Range | 12.7 mm (500 mils), beginning at approximately 0.63 mm (25 mils) from target |
| Average Scale Factor (ASF) | 0.787 V/mm (20 mV/mil) nominal |
| Output Range | Approximately -1.5 Vdc to -11.5 Vdc |
| Deviation from Straight Line (DSL) | Less than +/-0.31 mm (+/-12 mils) |
| Output Resistance | 50 ohms |
| Frequency Response | 0 to 2.7 kHz: +0, -3 dB typical (up to 305 m of field wiring) |
| Recommended Target Size | 61 mm (2.4 in) minimum diameter flat target (AISI 4140 steel) |
| Housing Material | A380 aluminum |
| Field Wiring | 0.2 to 1.5 mm2 (16 to 24 AWG) terminal connections |
| Operating Temperature | -51 degC to +100 degC (-60 degF to +212 degF) |
| Storage Temperature | -51 degC to +105 degC (-60 degF to +221 degF) |
| Relative Humidity | 100% condensing, non-submersible (when connectors are protected) |
| Terminal Label | Connection Function |
|---|---|
| OUT | Signal output (analogue voltage representing displacement) |
| COM | Common return / ground reference |
| VTG | Power supply input (-17.5 Vdc to -26 Vdc) |
| Coaxial Connector | Connects to 3300 XL 25 mm extension cable / probe |
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| Country of origin |
United States
|