1790D-T0V32 Allen-Bradley Sinking Output Base

1790D-T0V32 24V DC Sinking Output Base Module

Product Introduction

The 1790D-T0V32 is a high-density sinking output module from the Allen-Bradley CompactBlock LDX series. It delivers 32 sinking outputs with a nominal 24V DC supply. Each output handles up to 0.5A, while each common supports 4.0A total. Additionally, the module includes 32 green status indicators for real-time monitoring. For DeviceNet communication, it produces 1 input byte with status and consumes 4 output bytes.

Key Technical Specifications

This module operates with sinking outputs. That means the output terminal switches the load to DC common. The on-state voltage ranges from 10V DC minimum to 28.8V DC maximum. Nominal voltage is 24V DC. Furthermore, the on-state voltage drop stays below 0.5V DC max, which reduces power loss and heat generation.

Important output parameters include:

• Minimum on-state current: 1 mA per channel

• Maximum off-state voltage: 28.8V DC

• Off-state leakage current: 0.5 mA max

• Output delay: Off to On in 0.5 ms max, On to Off in 1.0 ms max

The 1790D-T0V32 uses nonisolated outputs with 16 points sharing each common (16 points/2 COM). Consequently, you can group loads efficiently across two commons. Photocoupler isolation separates I/O from logic at 1250V AC rms, which protects the control system from field transients and noise.

DeviceNet Communication Data

This module has specific I/O data requirements for DeviceNet networks. It produces 1 input byte that contains status information. Additionally, it consumes 4 output bytes for controlling the 32 output points. The default configuration uses 0 input bytes, but with status enabled, it uses 1 input byte.

Data mapping summary:

• Input bytes produced: 1 (with status enabled)

• Output bytes consumed: 4

• Default mode: 0 input bytes

Therefore, when configuring your DeviceNet scanner, allocate 4 bytes of output data and 1 byte of input data for status. This setup allows you to monitor module health while controlling all 32 sinking outputs.

Power and Dissipation Details

For base module operation, the DeviceNet power supply requires 24V DC nominal. Its voltage range is 11…28.8V DC. Maximum power dissipation for the base module is 1.2W at 28.8V DC. Meanwhile, field power dissipation equals 6 mA at 28.8V DC per point. Therefore, a 32-point full load draws about 192 mA from the field supply.

On-state voltage requirements:

• Minimum: 10V DC

• Nominal: 24V DC

• Maximum: 28.8V DC

Current ratings to remember:

• Per output: 0.5A max

• Per common (16 points): 4.0A max

Mechanical and Wiring Specifications

The 1790D-T0V32 comes with a terminal block using M3.0 screws. The recommended screw torque is 7 lb-in maximum. Use only copper or copper-clad aluminum conductors for safe and reliable connections. Additionally, the module supports standard DIN-rail mounting. Its compact size saves valuable space inside control cabinets despite having 32 points.

Operating temperature ranges from 0°C to 55°C. Storage temperature spans -40°C to 85°C. Humidity tolerance is 5% to 95% non-condensing. Thus, the module fits most industrial automation environments without issue.

Installation Guidelines

First, disconnect all power sources before installation. Next, mount the 1790D-T0V32 securely onto a DIN rail. Then, connect the 24V DC field supply to the appropriate terminals. Wire each sinking output to your load's positive side, since the module switches the negative side. Finally, tighten all terminal screws to 7 lb-in max.

For instance, connect a solenoid valve coil between +24V and an output channel. When the output turns on, it completes the path to DC common. Remember to distribute current evenly across each common. Since each common handles only 4.0A, do not exceed this limit on any group of 16 outputs.

Typical Applications

You will find the 1790D-T0V32 in many high-density sinking output applications. Specifically, it works well for driving DC relays, small solenoids, indicator lights, and valve actuators. Additionally, it suits PLC output expansion in conveyor systems, packaging machines, and assembly lines. Because of its fast 0.5 ms response time, it also works in high-speed sorting or pick-and-place equipment.

The high channel count makes it ideal for applications with limited cabinet space. Instead of using multiple 16-point modules, a single 1790D-T0V32 provides 32 outputs in one compact package.

Packaging List

• 1790D-T0V32 module (32-point sinking output base)

• Terminal block with M3.0 screws pre-installed

• Product identification label

• Installation instruction sheet

Note: No certificates or warranty documents are included in the package.

Shipping Information

All orders ship via FedEx, UPS, or DHL. Tracking numbers are sent within 24 hours after dispatch. International delivery typically takes 3–7 business days.

Frequently Asked Questions (FAQ)

1. What does "produces 1 input byte with status" mean for the 1790D-T0V32?
The module sends one byte of status data back to the DeviceNet master. This byte contains information about module health, power status, and potential faults. It helps with diagnostics.

2. Can I disable the status byte to save I/O data?
Yes, the default configuration uses 0 input bytes. When you do not need status monitoring, you can run the 1790D-T0V32 without producing any input data. The outputs still function normally.

3. What is the difference between this sinking module and a sourcing one?
The 1790D-T0V32 sinks current to ground. Your load connects between +24V and the output. A sourcing module supplies current from the output to the load. Choose based on your field device wiring requirements.

4. How do I check the status of each output channel?
Each of the 32 outputs has a green LED indicator. When the output is actively sinking current, the LED lights up. This feature allows quick visual troubleshooting without a multimeter.

5. Is the 1790D-T0V32 compatible with the 1790D-T0B32 base module?
Yes, both belong to the 1790D CompactBlock LDX family. However, the 1790D-T0V32 is itself a base module. It connects directly to DeviceNet without needing another base unit.