Product Overview
From a maintenance engineer's perspective, the Allen-Bradley 1790D-T8A0 is a 120V AC 8-input base and expansion module designed for robust industrial control. Its nonisolated inputs simplify wiring while maintaining performance in typical factory environments.
Technical Specifications Breakdown
Key parameters for the 1790D-T8A0 are listed below for quick reference:
| Feature | Specification |
|---|---|
| Inputs per module | 8 points nonisolated |
| On-state voltage range | 85V ac min, 110V ac nom, 132V ac max |
| Input impedance | 18 kΩ |
| On-state current | 9 mA max @ 132V ac |
| Off-state voltage | 45V ac max |
| Input signal delay | Off to On: 10 ms, On to Off: 30 ms |
| Indicators | 8 green input status |
| Common type | 8 points/8 COM |
| DeviceNet power supply voltage | 24V dc nom, 11…28.8V dc range |
| Power dissipation (DeviceNet) | 1.2 W max @ 28.8V dc |
| External AC power supply voltage | 110V rms, 60 Hz |
| External AC power supply range | 85…32V rms, 47…63 Hz |
| Power dissipation (AC) | 3 W @ 132V ac |
| Isolation I/O to logic | Photocoupler isolation, 1250V ac rms/V ac |
| Field power | Non-isolation |
| Wiring terminal block | M3.0, screw torque 7 lb-in max (use copper or copper-clad aluminum conductors) |
| Recommended fusing | 1 A, 250V, normal blow |
Industry Applications
For example, in automotive assembly, the 1790D-T8A0 can handle limit switches or proximity sensors, with its 10 ms off-to-on delay ensuring accurate timing. In packaging systems, the 8 nonisolated inputs reduce wiring complexity, lowering installation costs. The DeviceNet interface enables centralized diagnostics, minimizing downtime.
Installation & Setup Guidance
Mount the base module securely using the terminal block with M3.0 screws torqued to 7 lb-in max. Use copper or copper-clad aluminum conductors for reliable connections. Ensure the external AC supply is within 85-132V rms at 47-63 Hz. For DeviceNet power, apply 24V dc nominal (11-28.8V dc range). The module's 8 green LEDs provide immediate input status feedback, aiding quick verification during commissioning.
Maintenance & Reliability
Periodically inspect the terminal block connections for tightness and signs of corrosion. The photocoupler isolation (1250V ac rms) protects logic circuits from surges. Given the nonisolated field power, ensure proper grounding of the cabinet to avoid noise. The 1A, 250V normal blow fuse protects the AC input circuit; replace only with the same rating.
Compatibility & Integration
The 1790D-T8A0 integrates with DeviceNet networks, supporting 8 inputs per module with 8 common points. It works as a base or expansion unit, allowing scalable I/O configurations.
Selection Guide & Purchasing Advice
When selecting this module, verify your DeviceNet power supply delivers 11-28.8V dc and your AC source matches 85-132V rms. The 1790D-T8A0 is available at AutoDCSTech, your trusted source for industrial automation parts. Please verify current lifecycle status and availability with AutoDCSTech before ordering.
Availability & Condition at AutoDCSTech
| Part Number | 1790D-T8A0 |
|---|---|
| Availability | In Stock |
| Condition | New |
| Warranty | One Year |
| Origin | US |
