Bachmann CM202 CAN Communication Module

The Bachmann CM202 (00012160-00), also cataloged as the CM202 CAN Communication Module, operates as a dedicated hardware component for 2-channel CAN communication within Bachmann M1 Automation System networks.

Hardware Specifications

Deterministic Network Routing and Backplane Integration

The module interfaces directly with the host controller via high-velocity backplane bus communication pathways, allowing real-time data sync across the physical network. Bus interface logic handles deterministic network transfers for J1939, DeviceNet, and CANopen profiles without incurring processing jitter. It scales I/O density requirements by transmitting up to 128 TxPDO and 128 RxPDO parameters per network channel, maintaining firmware flash compatibility across standard M1 controller variations.

Frequently Asked Questions

Q: What are the firmware flash compatibility requirements when replacing a legacy module variant?

A: The hardware requires the M1 system software version to support the corresponding device driver profiles configured via the Bachmann SolutionCenter. Ensure the controller firmware matches or exceeds the module revision level.

Q: How is the backplane bus current load affected when installing multiple modules?

A: Each interface draws power directly from the 5 V and 24 V internal backplane rails. Total current calculations must sum the module requirements against the maximum rating of the M1 power supply card to prevent voltage sag.

Q: What is the maximum physical isolation voltage rating between the two separate CAN interfaces?

A: Galvanic isolation blocks potential differences up to 500 V between the individual CAN channels and the internal system backplane components.

Field Installation Guidelines

• Bus Connection Sequence: Power down the entire M1 backplane rack before inserting or removing the module from the bus slots to avoid data disruption or electrical damage.
• Termination Resistor Placement: Install standard 120 Ohm termination resistors at the physical endpoints of each CAN bus segment to suppress signal reflections.
• Shield Grounding Matrix: Connect the CAN cable shield directly to the functional earth ground terminal rail at the cabinet entry bulkhead using low-impedance ground clamps.
• Baud Rate Constraints: Match network cable segment lengths to the configured baud rates, keeping total distances within 40 meters when operating at the maximum 1 Mbit/s velocity.