Allen‑Bradley 1715-A2A 2-Slot Redundant I/O Adapter Base Unit

Product Overview

Core Specifications

• Slot capacity: 2 dedicated slots for dual 1715-AENTR EtherNet/IP adapters
• Power supply input: 18–32 VDC nominal 24 VDC; dual isolated power terminals for redundant power feeds
• Max total power capacity: 10.4 A total; max 400 mA per adapter slot; max 3.2 A for fault-tolerant I/O loadsRockwell Automation
• Power dissipation: Maximum 8 W
• Communication interface: Two integrated 10/100 Mbps EtherNet/IP RJ45 ports (one per slot)
• Internal fuse: 4 A, 125 V built-in overcurrent protection
• Mounting: Standard 35 mm DIN rail installation
• Protection rating: IP20 for indoor cabinet deployment only
• Operating temperature: -25 ℃ ~ +70 ℃
• Storage temperature: -40 ℃ ~ +85 ℃
• Humidity: 5%–95% non-condensing
• Isolation: 50 V continuous basic insulation between Ethernet ports and DC power/backplane
• Weight: Approx. 283 g
• Expansion support: Connectable to 1715-A3IO I/O expansion bases via 1715-C2 extension cables, up to 24 I/O modules per dual adapter pairRockwell Automation
• Certifications: UL, cUL, CE, Class I Div 2 hazardous location compliant

Main Functions

1. Dual Redundant Communication Carrier
    
   Holds two 1715-AENTR EtherNet/IP adapters to form redundant network paths. If one network link or adapter fails, the backup channel takes over I/O data transmission instantly without process interruption.
2. Dual Redundant Power Distribution
    
   Two separate 24 VDC power input terminals allow connection to two independent power supplies. The base automatically switches power feed to sustain full rack operation when one power source drops out.
3. Backplane Power & Signal Routing
    
   Distribute stabilized 24 VDC backplane power and high-speed I/O bus signals to downstream 1715 digital/analog I/O expansion bases and field modules.
4. Hot-Swap Maintenance Support
    
   Enable live replacement of faulty 1715-AENTR adapters while the redundant I/O system remains online, eliminating full system shutdown for maintenance.
5. System Expansion Interface
    
   Work with 1715-C2 expansion cables to cascade multiple 1715-A3IO I/O bases, scaling fault-tolerant input/output channels for large process plants.
6. Built-in Circuit Protection
    
   Internal 4 A fuse provides overcurrent cut-off to prevent short-circuit damage to dual adapters and the entire redundant I/O rack.

Key Advantages

• True dual redundancy design covers both power supply and communication links, meeting SIL 2 / Category 4 high-availability process safety requirements
• Wide -25℃ to +70℃ operating temperature adapts to high-temperature power rooms and outdoor control cabinets
• Dual independent power input eliminates single-point power failure, critical for continuous production processes
• Plug-and-play redundant architecture requires no complex programming to activate failover logic
• Compact DIN rail form factor saves cabinet space compared to separate non-redundant backplane assemblies
• Hazardous location certification supports oil & gas, chemical and petrochemical plant Class I Div 2 applications
• Hot-swap adapter capability drastically reduces unplanned downtime during equipment troubleshooting and replacement

Typical Applications