Overview
The Allen-Bradley 1746-NI16I Series A is a high-density 16-point analog current input module engineered for SLC 500 control systems. This single-slot module converts analog current signals into digital data for use by SLC 500 processors. The 1746-NI16I accepts multiple input ranges and delivers precise process signal acquisition for temperature, pressure, flow, level, and other industrial measurements.
Key Features
- 16 Isolated Analog Input Channels – Arranged in 4 isolated groups of 4 inputs each with group common, reducing noise and crosstalk in noisy industrial environments
- Multi-Range Input Support – Configurable for 0–20 mA, 4–20 mA, ±20 mA, 0–1 mA, plus voltage ranges (0–10V, ±10V, 1–5V, 0–50V)
- 16-Bit Resolution – Sigma-Delta A/D conversion with 640 nA input resolution and 1 μA display resolution for high-precision measurements
- Programmable Digital Filter – 6–250 Hz bandwidth with user-selectable low-pass filtering and step response from 9 to 630 ms
- Backplane Isolated Design – 500V AC / 710V DC isolation (tested 60s) protects processor from field noise and surges
- LED Status Indicators – Five indicator lights for quick module and channel diagnostics
Technical Specifications
- Input Channels: 16 (single-ended, isolated in groups of 4)
- Input Ranges: ±20 mA, 4–20 mA, 0–20 mA, 0–1 mA, ±10V, 0–10V, 1–5V, 0–50V (via programming)
- Resolution: 16-bit; Input resolution 640 nA; Display resolution 1 μA
- A/D Conversion Method: Sigma-Delta
- Bandwidth: 6–250 Hz (programmable digital filter)
- Step Response (95%): 9–630 ms
- Backplane Current Load: 125 mA @ 5V DC; 75 mA @ 24V DC
- Power Consumption: 2.425 Watts max (0.625W @ 5V; 1.8W @ 24V)
- Common Mode Voltage Range: ±10.25V (relative to analog common)
- Max Input Voltage (without damage): ±8V between analog common and input terminal
- Max Input Current: ±30 mA
- Input Impedance: 249 Ω
- Operating Temperature: 0 to 60 °C (32 to 140 °F)
- Non-Operating Temperature: −40 to 85 °C (−40 to 185 °F)
- Relative Humidity: 5 to 95% (without condensation)
- Isolation Voltage: 500V AC / 710V DC (60s test)
- Module Type: Single-slot SLC 500 I/O module
- Mounting: SLC 500 chassis
- Weight: 0.98 lb (0.45 kg)
- Connection: Removable terminal block (requires 1746-RT25G)
Typical Applications
- Analog sensor signal acquisition (pressure transducers, temperature transmitters, load cells)
- Process variable monitoring in manufacturing and chemical plants
- Industrial HVAC and environmental control systems
- Water and wastewater treatment systems
- Energy and utility monitoring
- Food and beverage processing lines
- Motor speed and torque control feedback systems
Compatibility & Replacements
Compatible With
- Allen-Bradley SLC 500 fixed CPU (1747-L511, 1747-L512, 1747-L513, 1747-L514, 1747-L515)
- Allen-Bradley SLC 500 modular CPU (1747-L531, 1747-L532, 1747-L533, 1747-L542, 1747-L543, 1747-L553)
- SLC 500 I/O chassis and backplane systems
- RSLogix 500 engineering software
- Allen-Bradley PLC-5 systems (via communication modules)
Replaces / Drop-In Replacement For
- 1746-NI16I (earlier revisions and versions)
- Compatible with systems previously using 1746-NI4 modules (with program scaling adjustments)
Works With
- RSLogix 500 programming software
- SLC 500 I/O configuration and monitoring tools
- Third-party SCADA and HMI systems supporting SLC 500 interface
- Remote I/O and communication gateway modules for networked applications
