PRODUCT INFORMATION
Product Overview
The Allen-Bradley 1794-OA8 is a FLEX I/O Digital Output Module. It provides eight non-isolated AC outputs grouped into a single circuit. The module operates within an AC line voltage range of 85 to 132 Volts AC. It uses a nominal operating voltage of 120 Volts AC. The unit consumes 80 mA of FlexBus current at 5 Volts DC. The module provides continuous isolation voltage rated at 120 Volts.
Total module current capacity is 4 Amps across all eight outputs at 500 mA each. Current capacity varies with ambient operating temperature. At 55 degrees Celsius, current capacity reaches 500 mA per output. At 35 degrees Celsius, each output delivers up to 750 mA. At 30 degrees Celsius, four non-adjacent outputs deliver 1 Amp while four deliver 500 mA. Maximum power dissipation is 4.1 Watts at 0.5 Amps and 6.3 Watts at 1 Amp.
TECHNICAL DATA
Technical Specifications
| Parameter | Specification |
|---|
| Product Line | Flex I/O 1794 |
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| UPC | 612598137848 |
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| Weight | 0.56 lbs (0.26 kg) |
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| Outputs | 8 Nonisolated |
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| Output Voltage nom. | 120V AC |
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| Output Current Rating | 4.0A |
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| On-state Current min. | 5mA per Output |
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| On-state Voltage Drop max. | 1.0V @ 0.5A max. |
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| Off-state Leakage Current max. | 2.25mA |
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| Isolation Voltage | 120V Continuous |
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| Flexbus Current | 80mA @ 5V DC |
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| Power Dissipation | 4.1W @ 0.5A max. |
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| Thermal Dissipation | 14.0 BTU/hr. @ 0.5A max. |
|---|
TECHNICAL INFORMATION
Features
- Provides eight non-isolated 120V AC output points arranged in a single group.
- Delivers an aggregate output current rating of 4 Amps.
- Withstands surge currents up to 7 Amps for 40 milliseconds every 8 seconds.
- Limits turn-on and turn-off signal delay to a maximum of one-half cycle.
- Features diagnostic capability for I/O field devices, wiring, and the power supply.
- Operates with a maximum on-state voltage drop of 1.0 Volt at 0.5 Amps.
TECHNICAL INFORMATION
Connections / Interfaces
- Connects to the FLEX I/O backplane via the internal 80 mA 5V DC FlexBus interface.
- Installs directly onto compatible 1794 terminal base units for field wiring connections.
TECHNICAL INFORMATION
Installation Guidelines
- Mount the module directly onto a compatible FLEX I/O terminal base unit.
- Install auxiliary terminal strips when using the 1794-TBN terminal base unit.
- Ensure system thermal dissipation can handle up to 21.4 BTU per hour.
TECHNICAL INFORMATION
Configuration Guidelines
- Verify that individual output loads match the temperature-dependent current derating limits.
- Ensure aggregate output current does not exceed the 4.0 Amp total module rating.
TECHNICAL INFORMATION
Compatibility
- Compatible with terminal base units 1794-TB2, 1794-TB3, 1794-TB3S, 1794-TB3K, and 1794-TB3SK.
- Compatible with terminal base units 1794-TBN, 1794-TBNF, 1794-TBNK, 1794-TBKD, and 1794-TBNFK.
TECHNICAL RESOURCES
Documentation
COMPATIBILITY
Compatibility & Replacement
COMPATIBLE MODELSCompatible with terminal base units 1794-TB2, 1794-TB3, 1794-TB3S, 1794-TB3K, and 1794-TB3SK. Compatible with terminal base units 1794-TBN, 1794-TBNF, 1794-TBNK, 1794-TBKD, and 1794-TBNFK.
Verify compatibility against the exact Part Number, revision and manufacturer documentation before ordering.
PART VERIFICATION
Before You Order
Industrial automation parts can share similar model names, suffixes and revisions. Confirm the complete manufacturer Part Number before purchase.
01Check Part NumberMatch the complete ordering code on the existing unit.
02Confirm RevisionCheck suffix, hardware or firmware when applicable.
03Send a Label PhotoWe can review a clear label photo when identification is uncertain.
ORDERING PROCESS
From RFQ to Dispatch
1Submit Part Number2Verify Product Identity3Confirm Stock & Condition4Issue Quotation5Dispatch & Tracking
PRODUCT FAQ
Frequently Asked Questions
What terminal base units support the Allen-Bradley 1794-OA8?
The module installs on 1794-TB2, 1794-TB3, 1794-TB3S, 1794-TB3K, 1794-TB3SK, 1794-TBN, 1794-TBNF, 1794-TBNK, 1794-TBKD, and 1794-TBNFK bases. When using the 1794-TBN base, auxiliary terminal strips are required.
What is the maximum output current rating for the 1794-OA8?
Total aggregate output current is 4.0 Amps. Individual point ratings depend on ambient operating temperature. At 55 degrees Celsius, each output handles 500 mA. At 35 degrees Celsius, each output handles 750 mA.
What is the indicative market reference price for the 1794-OA8?
Observed market reference pricing is approximately $97.00 USD. This figure is an indicative market reference price only and is not a final quotation.
What are the power dissipation ratings for the 1794-OA8?
Power dissipation is 4.1 Watts at 0.5 Amps. Power dissipation reaches 6.3 Watts at 0.75 Amps and 1.0 Amp.
