Product Overview
When your control system needs reliable analog signal acquisition, the Allen-Bradley 1794-IE8 Flex I/O analog input module delivers eight single-ended, user-configurable channels that accept 0–20 mA, 4–20 mA, ±10 VDC, and 0–10 VDC signals. Part of the Flex I/O family, the 1794-IE8 interfaces seamlessly with Flex I/O communication adapters and terminal bases to build a distributed I/O architecture.
This high-density module is engineered for industrial environments where accuracy and durability matter. With a successive approximation conversion type and 16-bit 2’s complement left-justified data format, it ensures precise data representation for your PLC or DCS.
Technical Specifications
The Allen-Bradley 1794-IE8 offers the following key parameters:
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No. of inputs: Eight (8) single-ended
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Input type: 0–20 mA, 4–20 mA, ±10 VDC, 0–10 VDC
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Resolution: 12 bits unipolar; 11 bits plus sign bipolar (voltage: 2.56 mV/cnt unipolar, 5.13 mV/cnt bipolar; current: 5.13 µA/cnt)
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Absolute accuracy: 0.20% full scale @ 25°C
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Accuracy drift with temperature: Voltage terminal 0.00428% FS/°C; current terminal 0.00407% FS/°C
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Conversion rate: 256 µs (all channels)
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External DC supply: 24V DC nominal; range 10.0…31.2V DC (includes 5% AC ripple)
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FlexBus current: 60 mA
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Power dissipation: 3.0W at 31.2V DC
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Thermal dissipation: 10.2 BTU/hour at 31.2V DC
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Isolation voltage: 50V continuous
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Operating temperature: 0 to 55°C (32 to 131°F)
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Storage temperature: –40 to 85°C (–40 to 185°F)
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Vibration: 5g @ 10 to 500 Hz
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Mounting: DIN rail
Key Features & Benefits
- Eight single-ended channels reduce wiring complexity and save space.
- Supports both current and voltage signals, offering flexibility for various field instruments.
- Successive approximation conversion ensures fast and stable readings.
- No calibration required beyond factory settings, simplifying maintenance.
- Compatible with multiple terminal bases (1794-TB2, -TB3, -TB3S, -TB3T, -TB3TS) for easy installation.
Industry Applications
The Allen-Bradley 1794-IE8 is ideal for process control, manufacturing automation, and machine monitoring. It interfaces with field transmitters, analog indicating instruments, recorders, and process loop controllers. For example, in a chemical plant, the module captures 4–20 mA signals from pressure transmitters, enabling precise process regulation. In a packaging line, it reads 0–10 VDC from position sensors to synchronize motion control.
Because of its high accuracy (0.20% FS) and temperature stability, the 1794-IE8 suits applications where consistent performance across temperature variations is critical.
Installation & Setup
Mount the 1794-IE8 on a DIN rail using a compatible terminal base (1794-TB2, -TB3, -TB3S, -TB3T, or -TB3TS). Connect the external DC supply (24V DC nominal, range 10.0–31.2V DC) and route field wiring per the terminal base's wire size specifications. The module's green/red power/status indicator helps confirm proper operation. No calibration is required.
Compatibility & Integration
The 1794-IE8 works with Flex I/O communication adapters for Ethernet, ControlNet, and Remote I/O networks, integrating easily into Rockwell Automation systems. It also pairs with any controller that supports Flex I/O architecture, making it a versatile choice for system expansion or upgrades.
Maintenance & Reliability
With no calibration needs, the 1794-IE8 reduces downtime and maintenance costs. Its robust design withstands vibration up to 5g and temperatures from 0 to 55°C, ensuring reliable operation in demanding environments. Periodic inspection of connections and terminal bases is recommended to maintain signal integrity.
Selection Guide & Purchasing Advice
Before purchasing, verify your required input signal types and terminal base compatibility. The 1794-IE8 is available now at PLC Source PRO, a trusted supplier of industrial automation spares. Ensure you order the correct catalog number 1794-IE8 for your application.