I. Product Introduction

NI SCXI-1302 is a 50-pin high-density shielded front-end connector board for the SCXI platform, not a collection module, used to provide signal conversion for SCXI-1100/1102B/C/1104/C and other 32-channel analog input modules. It features a fully shielded metal casing and screw terminals, supports differential/single-ended signal configurations, integrates stress elimination fixtures, is suitable for industrial and laboratory multi-channel signal acquisition, has been discontinued, and provides spare parts and technical support.

II. Model Interpretation

SCXI: Instrument Signal Conditioning Expansion Series.

1302: Basic model, representing 50-pin terminals, high-density shielded termination board.

Component Number: 777687-02.

Series Positioning: 1300 (32-channel universal) → 1302 (50-pin high-density) → 1303 (thermocouple-specific), channel density and shielding level increase.

III. Technical Parameters

Terminal Configuration: 50 screw terminals, supporting 32 differential or 16 single-ended signals.

Wire Specifications: Compatible with 26–16 AWG wires.

Rated Voltage: 300 V AC/DC (terminal to terminal).

Rated Current: 5 A per terminal (continuous).

DC Suppression: ±50 VDC, cut-off frequency 0.16 Hz (1 pole RC).

Insulation Resistance: ≥1 MΩ (500 V DC).

Operating Temperature: 0～55 ℃; Storage - 40～85 ℃.

Humidity: 5%～95% without condensation.

Shielding Effectiveness: Metal casing + internal isolation sheet, CMRR ≥100 dB.

Size: Standard SCXI front panel size; Weight approximately 0.5 kg.

IV. Interface and Communication Configuration

Front Panel: 50 screw terminals, including signal terminals, chassis ground, shielding ground, and stress elimination fixture.

Back Panel: 50-pin DIN connectors, directly connected to the front end of the SCXI module, without independent communication bus.

Installation Method: Front-end embedded installation, supports rack and DIN rail installation.

Software Support: Compatible with NI-DAQmx driver, compatible with LabVIEW, C/C++, LabWindows/CVI.

V. Core Functions

High-density Signal Conversion: 50 terminals support 32 differential or 16 single-ended, suitable for high-channel-count acquisition requirements.

Full Shielding Anti-interference: Metal casing + internal isolation sheet, suppresses EMI and channel crosstalk, ensures weak signal integrity.

Flexible Signal Configuration: Differential / single-ended selectable, suitable for voltage, current, sensor and other signal types.

Reliable Mechanical Design: Screw terminals are tightened, stress elimination fixture prevents wire loosening, resistant to vibration and suitable for industrial environments.

Ground Optimization: Independent chassis ground and shielding ground terminals, reduce ground potential difference interference, improve common-mode suppression capability.

VI. Application Scenarios

Multi-channel Voltage Acquisition: High-density signal conversion for 32-channel sensors and transmitters in industrial sites.

General Signal Conditioning: Combined with SCXI-1102B/C/1104/C modules, build high-channel-count analog input systems.

Industrial Automation: Production line data acquisition, equipment status monitoring, suitable for harsh electromagnetic environments.

Laboratory Measurement: Multi-channel precise voltage and current measurement, provides stable shielding interface.

Mixed Signal System: Combined with other SCXI modules to build low-frequency/high-frequency mixed test systems.

VII. Usage and Maintenance Instructions Instruction Manual

Power-off installation: Align the terminal board with the front end of the SCXI module, push it in smoothly and secure it, ensuring that the 50-pin connector is fully attached.

Wiring specification: Connect signals according to the terminal labels, with the differential positive and negative ends connected correspondingly; use wire specifications of 26–16 AWG, and tighten the screws to prevent loosening.

Grounding treatment: Connect the shield ground to the earth, and connect the chassis ground to the module ground to reduce ground potential difference interference.

Software configuration: Set the differential / single-ended mode in NI-DAQmx, matching the module channel configuration.

Avoid overloading: The terminal voltage and current must not exceed the rated value to prevent burning of the terminal board or module.

Maintenance instructions

Environment: Maintain ventilation and dryness, temperature 0-55 ℃, away from dust, corrosive gases and strong electromagnetic interference.

Regular inspection: Check monthly for any loosening or oxidation of the screw terminals, and for any damage to the insulation layer of the wires. Tighten or replace promptly.

Cleaning: After power-off, wipe the terminals and the casing with isopropyl alcohol, dry them before powering on; do not allow liquids to enter the connector interior.

Troubleshooting: When there is abnormal signal, prioritize checking the wiring, terminal tightness, and shielding grounding; poor connector contact is mostly due to dust or oxidation.

Long-term storage: After power-off, remove the terminal board, clean the terminals, put them in an anti-static bag, and store in a cool and dry place.