Product Overview
The Allen-Bradley 20-COMM-E (20COMME) is a high-performance internal communication adapter designed to provide seamless EtherNet/IP connectivity for PowerFlex 7-Class AC drives and other compatible hardware. In complex industrial ecosystems such as oil refineries, automotive plants, and large-scale power generation facilities, the 20-COMM-E acts as a critical gateway, enabling real-time data exchange and remote diagnostic capabilities. By facilitating high-speed integration with Logix-based controllers, this module significantly reduces commissioning time and minimizes the risk of extended system downtime through enhanced fault reporting and remote configuration.
Technical Configuration (Deep Dive)
The 20-COMM-E hardware architecture is engineered for high-speed, full-duplex communication over standard Ethernet infrastructure. It supports 10/100 Mbps auto-sensing, ensuring compatibility with varying network speeds without manual intervention. The module interfaces directly with the drive’s internal DPI (Drive Peripheral Interface), allowing it to access all drive parameters, monitor real-time status, and execute control commands.
Key features include an integrated web server, which permits users to view drive information and configure network settings via a standard web browser. The adapter also supports "Producer/Consumer" data models, which optimize network bandwidth by allowing multiple controllers to listen to the same data broadcast from a single drive. For advanced automation setups, it provides full support for Faulted Node Recovery and BootP/DHCP for automated IP address assignment.
Technical Specifications
| Feature |
Specification |
| Model |
20-COMM-E |
| Brand |
Allen-Bradley (Rockwell Automation) |
| Series |
PowerFlex Communication Modules |
| Protocol |
EtherNet/IP |
| Communication Speed |
10/100 Mbps (Full or Half Duplex) |
| Input Voltage |
5 VDC (via DPI port) |
| Current Consumption |
350 mA at 5 VDC |
| Operating Temp |
-10 to 50 deg C |
| Storage Temp |
-40 to 85 deg C |
| Dimensions |
19 x 86 x 78.5 mm |
| Weight |
0.08 kg |
Technical FAQs
Q1: Which Allen-Bradley drives are compatible with the 20-COMM-E adapter?
A1: The 20-COMM-E is primarily designed for the PowerFlex 7-Class drives, including the PowerFlex 70, 700, 700H, 700S, and 753/755 (via a carrier). It is also compatible with SMC Flex and SMC-3 smart motor controllers.
Q2: How do I reset the module to its factory default IP address?
A2: You can perform a factory reset by setting the hardware rotary switches (if applicable to your specific hardware revision) or by using a tool like BOOTP/DHCP Server to clear the current configuration. Alternatively, you can reset parameters via the drive's HIM (Human Interface Module).
Q3: Does this module support Ring topology?
A3: The standard 20-COMM-E is a single-port device and does not natively support Device Level Ring (DLR) topology. For DLR requirements, a dual-port adapter like the 20-750-ENETR or an external tap is typically required.
Engineering & Installation Guide
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DPI Connection Integrity: Ensure the ribbon cable between the 20-COMM-E and the drive's internal DPI port is fully seated and locked. A loose connection can cause intermittent "DPI Port 5 Loss" or "Comm Loss" faults that are difficult to diagnose.
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Network Isolation: For high-performance motion or precise control, isolate the drive network from the plant-wide office network using a managed switch or VLAN. This prevents broadcast storms from affecting drive response times.
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Grounding and EMI: Ensure the Ethernet cable is Category 5e or higher and properly shielded if routed near high-voltage motor leads. The drive chassis must be grounded to a common bus to prevent common-mode noise from disrupting the communication processor.
Engineering Advantages
The 20-COMM-E stands out for its robust resilience in high-interference environments. Its internal logic is hardened against the electromagnetic noise typically generated by high-power VFD switching circuits. Furthermore, the adapter supports Flash-updatable firmware, allowing engineers to implement the latest security patches and protocol enhancements without replacing hardware. This longevity ensures that existing PowerFlex installations remain compatible with modern EtherNet/IP standards and Industry 4.0 data strategies.