Technical Specifications
| Parameter Name | Parameter Value |
|---|---|
| Product Model | 1203-CN1 |
| Manufacturer | Allen-Bradley (Rockwell Automation) |
| Product Type | ControlNet Communications Module / SCANport External Coupler |
| Series | 1203 Communication Adapter Series |
| Network Protocol | ControlNet, 5 Mbps, deterministic |
| SCANport Interface | 8-pin circular mini-DIN connector, single-device connection |
| ControlNet Interface | 2 × BNC coaxial ports (Channel A / Channel B), redundant-media capable |
| Configuration Port | RS-232 serial (9-pin, 9600 baud default; 2400 / 4800 / 19.2k / 38.4k selectable) |
| Input Power | 24 VDC (−20% / +30%) |
| Current Consumption | 250 mA maximum |
| Node Address Range | 0–99 (push-button switches, power cycle required) |
| I/O Data (Default) | 16-bit Logic Command/Status; 16-bit Reference/Feedback |
| Datalinks | Configurable; disabled by default |
| Serial Cable | 1203-SFC (required for configuration) |
| Status Indicators | 4 bi-color LEDs: Module, ControlNet A, ControlNet B, SCANport |
| Firmware | Flash-upgradeable (v2.001 and above support DriveExplorer v1.01+) |
| Mounting | 35 mm DIN rail (snap-on) |
| Enclosure Rating | IP20 (open type, cabinet installation required) |
| Dimensions (H × W × D) | 3.920 × 3.540 × 2.690 in (approx. 99.6 × 89.9 × 68.3 mm) |
| Weight | 0.52 lb (0.24 kg) |
| Operating Temperature | 0 °C to +55 °C (some literature lists 0 °C to +60 °C) |
| Storage Temperature | −40 °C to +85 °C |
| Relative Humidity | 5% to 95% RH, non-condensing |
| Certifications | UL 508, cUL, CE (EMC), ControlNet International conformance |
| Lifecycle Status | Discontinued by manufacturer (2015); supplied as new-surplus / refurbished |
Main Features and Advantages
Deterministic ControlNet communication with a dual messaging model
The 1203-CN1 exploits ControlNet’s time-division-multiplexed architecture to carry scheduled I/O traffic and unscheduled explicit messages simultaneously. Scheduled data—logic commands, speed or torque references, status and feedback—is delivered within the configured Network Update Time, which is what makes the module suitable for coordinated, time-critical drive control. Unscheduled messaging runs in the same network without disturbing that schedule, carrying parameter reads and writes, fault queries, and configuration traffic. The result is that a ControlLogix processor can both regulate a drive in real time and interrogate its parameters remotely, using the same network connection.
One device, one node, no shared-link ambiguity
Unlike multi-drop gateway modules that serve several devices through one network connection, the 1203-CN1 connects to exactly one SCANport product. That product receives its own ControlNet node address, its own scheduled connection, and its own unscheduled bandwidth. This simplicity has real maintenance value: when a drive stops communicating, the fault is isolated to one module and one device, and the diagnostic LEDs on that module identify immediately whether the problem lies with the module, the network, or the SCANport connection.
Redundant media support through dual coaxial ports
The 1203-CN1 carries separate Channel A and Channel B BNC ports, allowing it to participate in redundant ControlNet media configurations. Where network availability matters—continuous process lines, material handling systems with coordinated drives, and remote pump stations—the second channel provides a failover path if the primary coaxial trunk is damaged. Combined with ControlNet’s tap topology, this allows a single cable break to be tolerated without bringing down the connected device.
