Bonfiglioli EM-ENC-02 Expansion Module Engineering Configuration Guide

Bonfiglioli EM-ENC-02 Expansion Module Engineering Configuration Guide

In industrial automation drive systems, frequency converters often require additional I/O, encoder feedback, or fieldbus communication capabilities to meet the needs of complex applications. Bonfiglioli provides the EM-ENC-02 expansion module for ACT and ACU series inverters, which integrates CAN system bus interface, bipolar analog input/output, incremental encoder input, programmable digital port, and motor PTC temperature measurement function. It is an ideal component for building distributed motion control networks. This article provides a detailed explanation of the key steps of hardware installation, system bus configuration, process data exchange, analog calibration, and encoder debugging for this module from an engineering practice perspective, helping on-site engineers quickly master its configuration skills.

Module overview and application scenarios

The EM-ENC-02 expansion module is installed in the lower expansion slot of the frequency converter, achieving "plug and play" through a unified interface. Its main functions include:

CAN system bus (compliant with ISO-DIS 11898, up to 1 Mbaud), supporting CANopen protocol framework;

1 bipolar analog input (± 10 V or ± 20 mA, 12 bit resolution);

1 analog output (0-20 mA);

1-channel incremental encoder input (TTL/HTL, up to 300 kHz, supports direction recognition);

1 programmable digital port (input/output optional);

1-channel PTC thermistor or bimetallic temperature switch input.

This module is particularly suitable for situations that require multi machine synchronization (electronic gears), remote setpoint setting, actual speed feedback, and temperature monitoring, such as winding equipment, cranes, conveyor lines, and pump control.

Mechanical installation and safety precautions

1. Installation steps

The frequency converter must be completely powered off and wait for the DC bus capacitor to discharge (at least 5 minutes).

Remove the lower cover plate of the frequency converter (exposing the expansion slot).

Align the EM-ENC-02 module with the slot and insert it vertically, ensuring that the pins are fully engaged.

Reinstall the cover plate, and the module will automatically recognize and activate after power on.

2. Safety points

It is strictly prohibited to plug or unplug modules while they are live, otherwise it may damage the circuit.

The PCB on the back of the module is exposed to avoid touch and prevent electrostatic damage.

All control signal wiring (analog, encoder, CAN bus) must be laid separately from power cables, using shielded twisted pair cables and grounded at one or both ends (it is recommended to ground both ends extensively).

System bus (CAN) interface configuration

The CAN interface of EM-ENC-02 supports multi node networking (up to 63 slave stations plus 1 master station), using a linear topology. The following are the key configuration parameters.

1. Node ID and baud rate

Node ID: Set through parameter 900 (Node ID), with a value range of 1 to 63. If set to 0, the frequency converter serves as the system bus master station; Set to -1 to disable the bus function (factory default).

Baud rate: Select through parameter 903 (Baud Rate), with options of 50, 100, 125, 250, 500, and 1000 kBaud. The baud rate determines the maximum bus length (e.g. 25 m at 1000 kBaud and 1000 m at 50 kBaud). Ensure that all nodes are consistent.

2. Bus terminal resistance

There are two dip switches S1 and S2 on the module, which are used to activate the terminal resistor:

Passive terminal: S1=ON, S2=OFF (default).

Active terminal: S1=ON, S2=ON (improves signal edge, suitable for long lines).

Note: Only physical head and tail nodes need to enable terminals, and intermediate nodes must be turned off (S1=OFF, S2=OFF).

3. Main station function (when 900=0)

The main station is responsible for managing network startup (sending the Start Remote Node command) and generating SYNC synchronization messages (for synchronizing PDO).

904 (Boot Up Delay): The delay time for the master station to wait for all slave stations to initialize, with a default of 3500 ms.

919 (SYNC Time): SYNC message sending cycle (ms), set to 0 to not send synchronization.

SDO and PDO communication mechanism

The system bus is based on the CANopen protocol (DS 301), transmitting parameters through SDO (Service Data Object) and real-time control data through PDO (Process Data Object).

1. SDO channel

Each node has two SDO channels: SDO1 (for parameter reading and writing) and SDO2 (reserved visualization tool).

Identifiers are assigned according to predefined connection sets and can also be modified through parameters 921 (RxSDO1 ID) and 922 (TxSDO1 ID) (0 indicates using default values).

If SDO2 is not needed, it can be turned off through 923 (SDO2 Set Active).

2. PDO channel

Each node supports 3 sets of TxPDO (transmit) and 3 sets of RxPDO (receive), with a maximum of 8 bytes of data per set.

The identifiers are set by parameters 924 to 929 (RxPDO1/2/3, TxPDO1/2/3), and the default values conform to the predefined connection set (such as TxPDO1=384+Node-ID).

Transmission mode: Set the functional mode of each PDO through 930~938 (0=off, 1=time triggered, 2=SYNC triggered). The time triggered interval is set by 931/933/935 in milliseconds.