The NI SCXI-1125 is an 8-channel isolation amplifier module that conditions and isolates analog signals within the SCXI system architecture. It delivers up to 300 Vrms working isolation between channels and earth, protecting sensitive instrumentation while maintaining signal integrity in industrial and laboratory environments. Each channel operates independently with programmable gain (1 to 2000), input ranges from ±2.5 mV to ±10 V, and configurable lowpass filtering. Extended voltage measurement to ±1000 VDC is achievable with compatible terminal blocks. The module achieves 16-bit resolution accuracy of less than 0.01% full-scale and supports thermocouple, millivolt, volt, and current signals with integrated cold-junction compensation.
Technical Specifications
Channels: 8 isolated analog input channels
Electrical Isolation: Up to 300 Vrms channel-to-channel and channel-to-earth; CE Category II double insulation
Input Ranges (Programmable per Channel): ±2.5 mV, ±5 mV, ±1 V, ±5 V, ±10 V, and 0 V to +10 V
Extended Ranges: Up to ±300 V (SCXI-1313), ±250 V (SCXI-1327), or ±1000 VDC with 680 Vrms rating (TBX-1316 terminal block)
Gain Settings: 12 programmable settings from 1 to 2000
Lowpass Filter: Programmable per channel at 4 Hz or 10 kHz
Accuracy: Less than 0.01% full-scale; 16-bit resolution
Cold-Junction Compensation: Supported; scannable in multiplexed mode
Operating Temperature: 0°C to +55°C (standard); -20°C to +70°C (extended)
Physical Dimensions: 7.4 × 6.8 × 1.2 inches; 22.6 oz
– Key Features
• Supports thermocouple, millivolt, volt, 0–20 mA, and 4–20 mA signals
• Multiplexed and parallel output modes for flexible DAQ integration
• Channel-to-channel electrical isolation for noise rejection
• Software-configurable per-channel settings via NI-DAQmx or traditional NI-DAQ drivers
– Typical Applications
Multichannel data acquisition in high-noise industrial settings, thermocouple measurement systems, isolated analog front-end for DAQ systems, and laboratory measurement platforms requiring channel-to-channel isolation.
– Compatibility & Integration
Connects directly to SCXI chassis and integrates with NI DAQ devices via SCXI bus. Compatible with NI-DAQmx (version 9.0 or later) and traditional NI-DAQ driver software.
