Description
Technical Specifications
| Parameter Name | Parameter Value |
|---|---|
| Product Model | Allen-Bradley 1794-IEB1 |
| Manufacturer | Allen-Bradley / Rockwell Automation |
| Product Type | FLEX I/O Analog Input Module |
| Number of Channels | 8 single-ended, non-isolated |
| Input Signal Range | Current: 0–20 mA / 4–20 mA; Voltage: ±10 V DC / 0–10 V DC |
| Resolution | Unipolar 12 bits; Bipolar 11 bits + sign |
| Conversion Type | Successive approximation |
| Conversion Time | 256 µs (all 8 channels) |
| Data Format | 16-bit, left-justified, 2’s complement |
| Voltage Resolution | Unipolar 2.56 mV/cnt; Bipolar 5.13 mV/cnt |
| Current Resolution | 5.13 µA/cnt |
| Absolute Accuracy | 0.29% Full Scale @ +25°C |
| Input Impedance (Voltage) | 100 kΩ |
| Input Impedance (Current) | 238 Ω |
| Overload Capability | 30 V DC continuous or 32 mA continuous (one channel) |
| Isolation Voltage | 850 V DC (user to system, tested 1 s) |
| Backplane Current | 20 mA @ 5 V DC |
| Supply Voltage | 24 V DC (19.2–31.2 V DC) |
| Supply Current | 60 mA @ 24 V DC |
| Power Dissipation | Maximum 3 W @ 31.2 V DC |
| Operating Temperature | 0°C to +55°C |
| Storage Temperature | -40°C to +85°C |
| Dimensions | 45.7 H × 94.0 W × 53.3 D mm |
| Compatible Terminal Bases | 1794-TB2, 1794-TB3, 1794-TB3S |
Main Features and Advantages
The Allen-Bradley 1794-IEB1 delivers exceptional channel flexibility that simplifies both system design and spare parts management. Each of the eight input channels is independently configurable as either current or voltage input, enabling the same module to accept a 4–20 mA pressure transmitter alongside a 0–10 V level sensor without requiring separate input card types. This flexibility reduces engineering complexity and inventory costs for mixed-signal applications.
Cost-Effective Non-Isolated Architecture: The Allen-Bradley 1794-IEB1 employs a non-isolated input design that maintains 850 V DC system-level isolation while reducing module complexity and cost . For the majority of industrial applications where field devices and control systems share a common ground reference, the non-isolated configuration delivers reliable measurement performance with favorable economics. This design choice positions the Allen-Bradley 1794-IEB1 as a practical choice for cost-sensitive projects that cannot compromise on signal integrity.
Removal and Insertion Under Power: The module supports RIUP capability, allowing technicians to replace a failed Allen-Bradley 1794-IEB1 without shutting down the FLEX I/O rack or interrupting field wiring. For water treatment facilities, continuous production lines, and other scenarios where extended downtime carries significant operational cost, this capability translates directly into measurable savings.
Fast Conversion with Deterministic Response: The 256 µs scan time across all eight channels provides the Allen-Bradley 1794-IEB1 with sufficient speed for pressure closed-loop monitoring, flow verification, and other applications where timely data refresh matters. The module delivers factory-calibrated accuracy without requiring field adjustment, eliminating calibration errors and reducing commissioning time.
Diagnostic Capabilities: The Allen-Bradley 1794-IEB1 includes power-up (PU) and underrange (U) status bits that provide basic diagnostics for 4–20 mA inputs . The underrange bit alerts maintenance personnel to sensor disconnection or signal loss, enabling faster troubleshooting without additional diagnostic hardware.
