Allen-Bradley 1790-T0B16X 0.5A DC I/O Module

Allen-Bradley 1790-T0B16X 16 Sourcing Output Module

Product Introduction

The Allen-Bradley 1790-T0B16X gives you 16 sourcing DC outputs in a compact base module. This unit operates directly from a 24V DC nominal field power supply. The on-state voltage ranges from 10V DC minimum up to 28.8V DC maximum. Each output channel sources 0.5A maximum continuously. Moreover, the on-state voltage drop stays below 0.5V DC at full load, which minimizes heat generation. The 1790-T0B16X also offers very fast response times. Turn-on delay measures just 0.5ms maximum, while turn-off delay reaches only 1.0ms maximum. For applications needing many DC outputs in a small footprint, this module provides an excellent solution.

Technical Specifications of the 1790-T0B16X

Output Characteristics

• Number of outputs: 16 points, nonisolated, sourcing type.

• On-state voltage: 10V DC min, 24V DC nom, 28.8V DC max.

• On-state voltage drop: 0.5V DC maximum.

• On-state current: 1 mA minimum per channel.

• Off-state voltage: 28.8V DC maximum.

• Off-state leakage: 0.5 mA maximum.

• Output signal delay (Off to On): 0.5 ms maximum.

• Output signal delay (On to Off): 1.0 ms maximum.

• Output current rating: 0.5 A maximum per output, 4.0 A maximum per common.

• Common type: 8 points share 8 COM terminals.

Power Specifications

DeviceNet Power (Base Module)

• Supply voltage: 24V DC nominal.

• Voltage range: 11…28.8V DC.

• Power dissipation: 1.2 W maximum at 28.8V DC.

Field Power

• Supply voltage: 24V DC nominal.

• Voltage range: 10…28.8V DC.

• Power dissipation: 6 mA at 28.8V DC per active point.

Isolation and Wiring

• Isolation (I/O to logic): Photocoupler isolation.

• Isolation voltage: 1250V AC RMS.

• Terminal block: M3.0 screws.

• Screw torque: 7 lb-in maximum.

• Conductor material: Copper or copper-clad aluminum only.

Indicators

• Status LEDs: 16 green indicators, one per output channel.

Mechanical and Environmental Data

This module weighs approximately 1.42 kg (3.13 lbs). The housing protects internal circuits from dust and vibration. Operating temperature ranges from 0°C to 55°C. Storage temperature extends from -40°C to 85°C. Relative humidity can reach 5% to 95% non-condensing. Additionally, the 1790-T0B16X meets standard industrial shock and vibration requirements. You can mount it on a standard DIN rail or directly on a panel. Always position the module away from high-voltage cables and heat sources to ensure reliable operation.

Installation Guidelines for the 1790-T0B16X

First, disconnect all power before starting any wiring. Connect the 24V DC field power supply to the designated V DC terminals. Then connect the corresponding COM returns. Because the 1790-T0B16X uses a sourcing output configuration, the load connects between the output terminal and COM. Each output channel can sink current from the load to ground. Use copper conductors with appropriate gauge for 0.5A per point. Tighten each M3 screw to exactly 7 lb-in. Over-tightening may strip the threads. Next, mount the module securely onto a DIN rail. Push the unit until the locking clip engages with an audible click. After wiring completes, apply power and check all 16 green LEDs. Each LED turns on when its corresponding output is active. Finally, verify that the field voltage stays within 10V to 28.8V DC. Lower voltages may not guarantee proper operation due to the 1mA minimum on-state current requirement.

Packaging List for the 1790-T0B16X

• One Allen-Bradley 1790-T0B16X Base Module (16 sourcing outputs)

• One product identification label sheet

• One printed quick start guide

• No mounting screws or brackets included

• No communication cables included

Note: This package does not include certificates or warranty documentation. Shipping invoices are separate.

Shipping Information

All orders ship via FedEx, UPS, or DHL depending on your delivery address. Standard transit takes 3-7 business days to major industrial areas. Tracking numbers are emailed within 24 hours after dispatch.

Frequently Asked Questions (FAQ)

1. What is the difference between sourcing and sinking on the 1790-T0B16X?
This module is sourcing. It supplies current from the output terminal to the load. The load’s other side connects to COM (ground). For sinking modules, the output terminal connects to ground and the load connects to a positive supply.

2. Can I use the 1790-T0B16X with a 12V DC field supply?
Yes, but with caution. The minimum on-state voltage is 10V DC. However, performance at 12V DC meets specifications as long as the load draws at least 1mA per channel. Do not exceed 28.8V DC.

3. How do I calculate total power dissipation for this module?
Add the base module dissipation (1.2W max) plus the field power dissipation. Each active output draws 6mA at 28.8V DC. For example, 16 active outputs consume 16 × 6mA = 96mA at 28.8V, which equals roughly 2.76W. Total is about 3.96W.

4. Is the 1790-T0B16X isolated from the DeviceNet side?
Yes. Photocoupler isolation provides 1250V AC RMS between I/O circuits and the logic side. This isolation protects the controller from field wiring faults.

5. What happens if I exceed 4.0A per common on this module?
The internal PCB traces or terminal block may overheat. The 4.0A per common limit is absolute. Distribute loads evenly across the eight COM groups. Each group serves two outputs. For instance, do not connect both 0.5A outputs to the same COM point if other loads already use that common.