Allen-Bradley 1790D-TN0C2: Precision Analog Output Module

Command analog devices with exceptional accuracy. The Allen-Bradley 1790D-TN0C2 provides two high-precision current output channels. It generates standard 0-20 mA signals to control devices like proportional valves, variable frequency drives, and analog meters. This module delivers stable, reliable commands for precise process regulation.

Detailed Technical Specifications

• Product Model: Allen-Bradley 1790D-TN0C2 (1790D Series Compact I/O).
• Output Channels: 2 single-ended, non-isolated current output channels.
• Output Signal: 0 to 20 mA standard industrial control signal.
• Resolution: 12-bit (4,096 steps), 4.88 µA per least significant bit.
• Accuracy: ±0.2% of full scale across 0 to 55°C operating temperature.
• Update Speed: 2 milliseconds per channel for rapid signal adjustment.
• Load Capacity: Supports external load resistance up to 600 Ω maximum.
• Power Supply: Requires 24V DC field power (21.6-26.4V) and DeviceNet bus power.

Installation & System Integration

• Wiring Connection: M3.0 screw terminal block for secure field wiring.
• Torque Specification: Tighten terminals to a maximum of 7 lb-in (0.79 Nm).
• Visual Diagnostics: Two bi-color (red/green) LEDs provide status for each output channel.
• Expansion Capacity: This base module can support up to two additional discrete I/O expansion modules.
• Calibration: Factory calibrated; no user calibration required, reducing maintenance effort.
• Isolation: 1250V AC RMS optical isolation between analog outputs and internal logic.

Packaging & Support Details

• Package includes one 1790D-TN0C2 analog output module.
• This precision module is covered by a standard 12-month warranty.
• Global shipping available via FedEx, UPS, and DHL for reliable delivery.

Expert FAQs

• What devices are typically controlled by this module?
  It's ideal for commanding proportional control valves, the speed reference input on variable frequency drives (VFDs), the setpoint input on process controllers, and analog panel meters or chart recorders.
• How do I convert the 0-20 mA signal to a 4-20 mA signal if my device requires it?
  Some end devices have a configuration switch or parameter to select 0-20 mA or 4-20 mA input. If not, you can use a signal isolator/conditioner between the module and the device to offset and scale the signal.
• Why is the maximum load resistance 600 Ω important?
  The module needs sufficient voltage to push the current through the loop. Using Ohm's Law (V=IR), at 20 mA into 600 Ω, you need 12V. The module's compliance voltage must be higher than this plus any other drops in the loop.
• Can the two channels output different current values independently?
  Yes. Each channel is controlled independently via the DeviceNet network. You can send separate command values to each channel for controlling two different devices.
• What happens if the output wire breaks or the load is disconnected?
  The output circuit will become open. Most systems will see this as a loss of signal (0 mA). Good system design includes monitoring at the receiving device or using isolators with broken wire detection to alert operators.

© 2025 Ubest Automation Limited. All rights reserved.
Original Source: https://www.ubestplc.com/
Contact: sales@ubestplc.com Phone: +86 180 3000 5825