I. Basic Information

Model: cFP-SG-140 (CFP-SG-140)

Manufacturer: National Instruments (NI)

Series: Compact FieldPoint (cFP)

Part Number: 777318-140

Status: Obsolete (Out of Production)

Location: High-precision strain / weighing / force / torque signal acquisition, dedicated to industrial bridge sensors

Type: 8-channel differential strain / bridge input module

II. Core Specifications (Channels / Electrical)

Number of channels: 8 differential inputs

ADC resolution: 16 bits (Δ-Σ)

Input impedance: 20 MΩ (high impedance, suitable for high-impedance bridges)

Supported bridge types:

Full bridge (Full-bridge): Direct connection

Half bridge (Half-bridge): Direct connection

Quarter bridge (Quarter-bridge): Requires external compensation resistor

Built-in excitation (optional): 2.5 V / 5 V / 10 VDC (per channel programmable)

Filtering (optional): 15 Hz / 60 Hz / 240 Hz (low-pass, suppresses power frequency noise)

Update rate: Approximately 0.9–1.15 seconds per channel

Isolation: Channel-backplane 250 Vrms CAT II

Accuracy: ±0.05% FS (typical, 25 °C)

Calibration: Factory NIST traceable calibration certificate

III. Wiring and Base

Required base: CFP-CB-1 (36-pin universal wiring base)

Wiring per channel:

EX+ / EX-: Excitation positive / negative

IN+ / IN-: Signal positive / negative (differential)

SENSE: Remote sensing (compensates for lead wire voltage drop)

Compatible sensors:

Strain gauges (full / half / 1/4 bridge)

Load cells (Load Cell)

Force sensors, torque sensors, pressure sensors (bridge type)

IV. Mechanics and Environment

Dimensions: 127 × 66 × 24 mm (standard cFP module)

Weight: Approximately 180 g

Installation: cFP-BP-4 / BP-8 base, hot pluggable (HotPnP)

Operating temperature: -40 °C ~ +70 °C

Storage temperature: -55 °C ~ +85 °C

Humidity: 10%–90% RH, no condensation

V. Compatibility

Base: cFP-BP-4 (4 slots), cFP-BP-8 (8 slots)

Controller: cFP-180x / 2000 / 2100 series

Software: LabVIEW, FieldPoint Explorer, Modbus RTU/TCP

VI. Discontinued Replacement (Direct Replacement)

Recommended replacement: NI-9237 (C series, 4-channel strain / bridge, 50 kS/s/ch, 24 bits, isolation, direct functional replacement)

Base replacement: NI-9923 (C series universal terminal base)

VII. Typical Applications

Structural stress / strain monitoring (bridges, buildings, equipment racks)

Industrial weighing systems (hoppers, belt scales, tank weighing)

Force / torque testing (test machines, motors, drive shafts)

Pressure / level sensor (bridge type) acquisition

Machine condition monitoring and fault diagnosis