Allen-Bradley 1790D-TN0C2 2-Channel Analog Current Output Module

Product Introduction

When precision analog output is critical for your process, the Allen-Bradley 1790D-TN0C2 delivers reliable 2-channel current control. This compact module provides 0-20 mA output with 12-bit resolution, ensuring accurate signal transmission for valve positioning, motor speed control, and other demanding applications. As part of the 1790D series, it integrates seamlessly into DeviceNet networks, reducing wiring costs and simplifying maintenance.

Technical Specifications Breakdown

The 1790D-TN0C2 offers two single-ended, nonisolated analog outputs with a resolution of 12 bits (1/4096 max, 4.88 µA/bit). This translates to fine granularity for precise adjustments, minimizing waste and improving product quality. The conversion time of 2 ms per channel enables fast response in dynamic processes, reducing cycle times and boosting throughput. Overall accuracy of 0.2% full scale at 0-55 °C ensures consistent performance across temperature variations, lowering recalibration costs. The module accepts DeviceNet power at 24V DC nominal (11-28.8V DC range) and field power at 24V DC nominal (21.6-26.4V DC), with maximum power dissipation of 1.2W and 1.5W respectively—keeping energy costs low. Isolation between I/O and logic uses photocoupler isolation with a type test of 1250V AC rms for 60 seconds, enhancing system reliability and reducing downtime risk.

Industry Applications

In chemical processing, the 1790D-TN0C2 controls dosing pumps with 0-20 mA signals, ensuring precise chemical addition that reduces raw material waste and improves batch consistency. For water treatment facilities, it adjusts variable frequency drives for pump speed control, optimizing energy consumption and lowering electricity bills. In packaging lines, the module manages servo valves for tension control, minimizing product damage and rework costs. Each application benefits from the module's high accuracy and fast conversion, directly impacting operational efficiency.

Installation & Setup Guidance

Mount the 1790D-TN0C2 on a DIN rail within an enclosure rated for the environment. Use copper or copper-clad aluminum conductors with a screw torque of 7 lb-in max for the terminal block (M3.0). Connect DeviceNet power (24V DC) and field power (24V DC) as per the wiring diagram. The module can accommodate a maximum of two discrete expansion modules, allowing scalable I/O without additional controllers. Ensure proper grounding to maintain isolation integrity and prevent noise interference.

Maintenance & Reliability

The 1790D-TN0C2 requires no calibration, eliminating recurring calibration costs and technician time. Its photocoupler isolation protects against voltage transients, extending service life and reducing unplanned downtime. Periodic inspection of connections and indicators (two red/green I/O status LEDs) helps catch issues early. With low power dissipation (1.2W max for DeviceNet, 1.5W max for field power), the module runs cool, reducing thermal stress on surrounding components and lowering cooling expenses.

Selection Guide & Purchasing Advice

Before purchasing the 1790D-TN0C2, verify your DeviceNet network compatibility and available power supply voltages (11-28.8V DC for DeviceNet, 21.6-26.4V DC for field power). Confirm the maximum external output load resistance of 600 ohms to ensure proper signal delivery. BluePLC Industrial offers this module with fast shipping and expert support to help you select the right configuration for your application. Contact our team for current lifecycle status and availability.